| Author | Message | ||
| turk713
New Username: turk713 Post Number: 3 Registered: 1-2004 |
I have had an ongoing distortion problem with my Orion 5-string bass and my Mesa/Boogie 400+ power tube head (the newer, early 90's 6-band EQ version), ever since I got the Mesa. With the Mesa I bought 2 early 90's Mesa RoadReady road cases, each housing 1 400W 15" EV. When I got up to what I call "a good rock and roll band playing volume" I got distortion on many B string notes. I reconed the speakers (they are out of production but the cones are still avail). No improvement occurred. So I replaced the speakers with new Eminence 500W 15" ones. No improvement; possibly a little worse. Now, this Mesa head is really powerful, with a very heavy sound. It also allows for a lot of user control, with no fancy frills. It allows for using either input you want, for both will work for any input gain, the difference is more a tonal thing than an active/passive thing. With either input, when I get to a good band playing volume I get distortion on the E string on frets 11 thru 13, and along the entire B string. By distortion I mean the typical farting sound of distorted output. Now, I have counted out all little things such as the battery in my Orion, and cables and effects. Also, my bass is in fine shape and it does not cause distortion thru other amps I have tried (they've been solid state). Also, other basses do not cause distortion thru my Mesa head and Mesa cases/speakers, even at noticeably higher volumes than the low range I have to stick with to get no distortion. The bass is good, the amp is good, and so are the speakers and the cases. Note that my new 500W speakers, as a pair, can handle more power than the presumed upper limit that the head can lay out. Yet my distortion occurs for me at an input gain setting of 2 and a master volume setting of 2.5! One difference though - my bass sounds so much more deep and powerful than do any of the basses I have tried with respect to this overall problem, even though I am at a lower audible volume. In the same respect, my Mesa head sounds immensely more powerful than do the solid state amps I have tried which have have a comparable or equal output power rating. The Mesa head supposedly puts out 360W normal max, but goes up to 400W, and even 500W in rare spikes. But this is an incredible 360W!!! It comes across as insanely powerful as a 1500W solid state amp I compared it with once. I'm thinking the problem is the combination of my Orion and my Mesa tube amp, as though the pair is simply too much. They even distorted a 6X10" SVT cabinet at the same output range as with other cabs, except just not quite as badly. Another guy's 15" and 18" cabs seemed to try to utterly shake apart with my Orion and my Mesa head, at a far less than band playing volume, although with the same cabs and his Schechtor active bass and his Peavey amp he is quite loud and clear in a classic rock band which goes for being loud as hell. One last note: it does not matter how I get to the audible volume where distortion occurs, it does occur just the same. By "how I get to it" I mean for example let's say I open the back of the bass and lower the output gain and then turn up the amp in any manner that gets me back up to the same audible volume, and there will be the distortion again. The same if I go to the other amp input, and so on. My questions are as follows. Has anybody run into this before? If so, how'd it get remedied? What cab(s) would work with my Orion and my tube head? It has pairs of 8ohm, 4ohm, and 2ohm outputs. Any other ideas about the cause of the distortion? What head and cab combo should I look into if need to start all over with a new rig? I am after a deep, heavy, clear, warm, powerful sound. That's why I got an Alembic and a tube amp. I feel totally frustrated. | ||
| lothartu
Member Username: lothartu Post Number: 70 Registered: 8-2003 |
That's really an odd problem. My first guess would be that the signal is too hot coming into the Mesa. Make sure you're using the active input on the Mesa since it's padded. If you can get a hold of an manual for the Mesa head then check and see if there are any miniswitches hidden in it that might control the amount of pad on the active input. You might need to adjust that. Hope this helps. - Jim (Message edited by LotharTu on December 12, 2004) | ||
| turk713
New Username: turk713 Post Number: 4 Registered: 1-2004 |
LotharTu, thank you for your reply. Your suggestions are good and well-reasoned ones. This problem however happens with both Mesa inputs. As an aside here, according to Mesa it is okay with any bass, active or passive, to use either input on this particular model amp. Although the two do have a significant power difference, according to Mesa the functional difference is largely just tonal. Using the lower gain input just means a significant reduction in ouput power and therefore requires an adjustment elsewhere to compensate, resulting again in the same distortion (which occurs at an output audible volume that is barely up to snuff for accompanying hard-hit drums, etc, in a rehearsal environment -- and it isn't nearly enough umph at that point to play an average club or party venue with no PA connection). The immediate point is again that in the end the difference between the inputs boils down to a tonal one. Also, yes I have referred to the amp manual and have also talked with Mesa regarding all amp controls. I believe that I have all bases covered in that regard. However, I have yet to pose the exact, general questions to Mesa that I have originally posted here earlier today, for it is only in the last couple days of trying other people's gear in varying combinations that I have considered the validity of such general questions regarding equipment matchup. A point I didn't mention in my original, long, problem description here is that recently my amp lab tested out to have no distortion at normal full power of 360W. But that was with a signal generator as input, not with my Alembic. But that just corresponds to the already mentioned fact that it doesn't happen with other basses as input into the Mesa head. As you said, "[it's] really an odd problem." I remain open to, and invite, more feedback. Sincerely, Turk. | ||
| mica
Moderator Username: mica Post Number: 2176 Registered: 6-2000 |
Have you tried turning the gain down inside the Orion? If the signal getting to the amp is too hot, turing that little trim pot dow should do the trick. | ||
| lothartu
Member Username: lothartu Post Number: 71 Registered: 8-2003 |
Just a quick thought. You could use a voltmeter to read the bass output current by measuring the difference directly at the end of the cable and then check the Mesa specs to see if it falls within what they consider to be an allowable range? (plug cable into bass, use voltmeter to measure current (in milliwatts?) at the other end of the cable, check Mesa specs) At least then Mica or another Alembician could confirm that the Alembic is outputting as it should. (even though you said that you adjusted the internal trimpot for the output gain this still might be worth checking, just to make sure the output voltage is within Alembic spec) Here's something else to check. Does the Mesa have an effects loop or a headphone out? If so then I'ld suggest plugging a set of headphones in and seeing if you're still getting the distortion. If you're not then at least you know that it's a post-preamp problem and not the bass. If you're still getting it then at least you know it's pre-poweramp. - Jim | ||
| gare
Intermediate Member Username: gare Post Number: 111 Registered: 11-2003 |
Turk I've also experienced a similar problem with my 400+. Mine was happening with both my Excel and a little with my Spector. First I swapped out all my cables wit h new Monster cables, which helped a little. Are you running anything thru the effects loop ? (I've been running a TC Elec M-One and a parametric EQ) I found the mix control for the efx round back of the amp is rather sensitive, at least on mine. After messing aorund with that and readjusting the input gain that the problem disappeared. The Alembics do have a hot signal. One last thing..how much time is on the tubes ? There may be a loose or bad one in the bunch. Hopefully you won't have the re-tube the whole amp. Gary | ||
| turk713
New Username: turk713 Post Number: 5 Registered: 1-2004 |
Hi Mica! Yes I played around with the Orion output gain pot and I found that it lowered the amp input gain as it should. So that lowered my final output volume. When I compensated for the volume loss, by any means, elsewhere in the system, I got the distortion back. Hi again Jim, you know, checking the bass output that way is an idea I had not considered exactly. Same with the Mesa headphone test; I will try both ideas. I Relatedly though, I plan this weekend to take my amp and bass out of state to a guy who can hook up a good signal generator to the amp, and voltmeter/o-scope test the output, and o-scope test the bass output for distortion, and then do the same with the amp output with the bass as amp input. Meanwhile I do have a voltmeter and I will test what you say. It could answer some questions before I haul things out of state. Hi Gary, so you found the same? I was HOPING to have run into somebody here who uses the same amp. Gary, I use the effects loop at times, yes, but not in my troubleshooting. I tried troubleshooting with effects connected through the loop and otherwise, but I found that effects added too many irrelevant variables to work around, insofar as the problem occurs without them. The effects loop mix control on the rear of the amp did not seem to help, although admittedly I did not try every possible permutation of other control settings while also manipulating the mix control. I tried the mix at 10 and at 5. Those two mix settings made no relevant difference, as I just indicated here a few lines up. Additionally I have found that running effects through the loop or not through it (i.e. inline between the bass and the preamp input) amounts to the same, relevant result here -- the same distortion. Of course when I do not use the loop I turn the mix control to zero; a Mesa rep told me that leaving it turned up can cause distortion, although I had not noted any difference in that specifically. I will go ahead and use the loop tonight and see how a bit more manipulation of the mix might help. The tubes? They are about a year old, and they all tested fine about 5 months ago. I'll have them looked at again this weekend. Gary, what is a TC Elec M-one? Speaking of pedals, I bought an ISP Noise Decimator which works while you play as well as when the strings are quiet. It appears to be irrelevant because it has not helped. Gary I'd love to know what cab(s) you use, and what speakers are in them, including the speaker power rating, the speaker freq response, and the cab impedance if you know all these things off the top of your head. This info would be very important to me. Additionally, do you now use an alembic with your Mesa? And, are you a loud player? Another question, Gary. If you have fixed the distortion you had, with effects out of the signal path (so that we can make a good comparison here), how high can you go now, with good sound, on the gain and master vol controls, and with which preamp input? And, these two settings, are they with an Alembic or one of your other basses? I know these are a lot of questions, and to whatever extent you can answer them I will be thankful. These are good suggestions everybody. I wholly appreciate them and I will appreciate more. Now here's a bit of news on the situation, acquired last night since I last wrote. I took Jim up on something he said about using the padded input, although Mesa says the amp is fine to use either input with any bass, and although I have tried both inputs before. Last night I found that with the lower gain input I could tweak other things and get a very slightly louder audible volume without distortion. Very slightly louder. I also lowered the pickup nearest the bridge. It was set high originally. I set it all the way down. It too allowed me a bit more good audible output. But the two little boosts I mention here do not add up too a significant amount. Helpful, yes, but not "a fix." I still wouldn't be able to fend for myself if my rig had to provide all the bass sound at a small gig with a loud band. I've still got the idea that I will end up having to get new output, ie cabs. Something like maybe 2 big SVT cabs at 4 ohms each. Something like that ought to make up the difference while keeping my controls at the same non-distorted settings I feel confined to using. I might end up looking for relevant suggestions before making such a money decision, as I originally posted here. I will update here as I try more things and get some up to date, electronic testing out of the way. THNX all, Turk | ||
| locutusofborg10
Junior Username: locutusofborg10 Post Number: 49 Registered: 11-2002 |
turk713 i had the same problem with my epic when i was using an Acoustic 370 head. the damn thing would just break up as soon as the volume reached 2 on the dial. i rolled back the output on the pot in the guitar, had my speakers checked, etc. all to no avail. i finally brought the head to someone in New York who i've been using for over 30 years. very simply, the two components just didn't match up. kind of like a bad marriage. i know my problem was with different equipment than yours, but it seems, for no explainable reason, that certain combinations don't work. luckily, i was able to swap the acoustic head for a gallien-krueger head. this combination seems to be a match made in heaven. with the gk i can't get distortion even if i want it. it's clean all the way to the max. i also run an swr and have no problems with that one, either. now whenever i'm looking for new equipment, whether it be amps or speakers, i take my bass with me. no more ebay or buying anything that i can't plug into right away. hope everything works out for you. | ||
| bsee
Senior Member Username: bsee Post Number: 568 Registered: 3-2004 |
I had a similar problem with a Zon bass and a Bass Pod XT. I played with the preamp gain inside the control cavity and it came nicely under control. Good luck! | ||
| turk713
New Username: turk713 Post Number: 6 Registered: 1-2004 |
Thank you, Locutusofborg10 and Bsee. Along with checking my bass output with a multimeter tonight, as Bsee and Mica suggest I will once more play with the gain pot in the elect. cavity of my Orion. Locutusofborg10, this is what I am coming to believe, that it is just not a good equipment matchup. Either that or I just need a lot more cabinet and speaker. Upcoming testing in a lab will help to determine that. Yeah, I played through my entire Mesa rig before I bought it, with my Orion. Trying things in a store, you know, is so nonrepresentative of actual playing. For one, you scare the store owner if you crank up to check for flaws! I appreciate that someone else has experienced a "bad equipment marriage." I didn't know if that notion was valid until you just said the same thing I am also considering as a cause. Again, thank you everybody. I still welcome more input. Turk | ||
| cntrabssn
Junior Username: cntrabssn Post Number: 30 Registered: 6-2002 |
Turk, It does seem like the Alembic is a bit too hot, but the comments you made about getting to a reasonable volume are pretty interesting. When you do this, are you mainly trying to reach desired volume using the individual channel volumes, or the master? As far as I know, the individual channel volume controls handle input gain, while the master controls overall level. I think you can try setting the channel volume control to the highest level short of distortion, then use the master to get your overall volume. If your bass' output signal is too hot you will find that distortion occurs a really low input gain settings. Like others said earlier, the trim pot in the bass should help. As a quick test, just try setting the trim pot to its minimum setting and try to get to a good volume as I mentioned above. Hopefully you'll be able to get a bit more useful range out of the input gain before distortion occurs, and you'll be able to get loud enough without having to really crank the master. Based on what I've seen in the manual, you'll probably want to stick with channel 1. I don't own a 400+, but I do have an M-2000. On the tube channel, I find that with my Alembic basses I have to set the gain pretty low, and compensate with the master volume to avoid distortion. By the way, if you haven't already, make sure you use the appropriate speaker output(s) for the combined impedance of your speakers. Good Luck, - nate. | ||
| lothartu
Member Username: lothartu Post Number: 73 Registered: 8-2003 |
No real new advice from me but I thought I'ld chime in anyways. I used to own a late 80's Series I and my band shared space with a couple of other bands. One night my amp head was out and one of the other bands bass players said I could use his rig for the night. It was a boogie 400+ with boogie 2x15 all in road cases. I don't remember having any distortion issues but I do remember being able to drown out everyone else in the band. That was an insanely loud rig when it's cranked up and the tubes are warmed. - Jim | ||
| gare
Intermediate Member Username: gare Post Number: 112 Registered: 11-2003 |
Hi Turk As far as my rig, I use the head thru a Mesa 4x10 Diesel cabinet with EV's. I picked up the cabinet about 1990 and honestly dont remember the power rating at the moment (heck,I cant remember Friday nite), but I'd imagine its about 400 watts, the response is around 45hz to 4000 hz,and an 8 ohm load. I use the cabinet with the horn shut off. I've also have 2 1x12 Avatar cabinets that sometimes get mixed in,both 8 ohm. The TC Electronics M-One XL is a rack mount multi effects processor,very nice chorusing,delays,etc. I also coaxed some nice tremolo effects out of it. I play an Excel with east meets west electronincs thru it. Since it has both a filter and active treble/bass controls,it can produce a fairly hot signal,so the gain on the active channel of the head only gets set at maybe 2 or 3. I also havent been using any of the boost controls or the graphic. None of the tone controls are set past 5. Also have a parametric eq patched in as the first link in effects, then to the effects processor. I find it easier for me to tweak certain frequencies this way. The distortion problem was weird and took me awhile to decipher. I dont play at high volumes, as Jim pointed out, that puppy can get damn loud. Its really more amp than I have a need for right now. So I'm looking into downsizing to a pair of small 1x15 cabinets,dont know which way to go yet for amp/pre amp etc. Gary | ||
| turk713
New Username: turk713 Post Number: 7 Registered: 1-2004 |
Hi again Mica, Gare, LotharTu, and now also Cntrabssn. Ok, last night I followed an above suggestion, checking the output of my Orion with a voltmeter. Maybe I didn't know how to do it, for in the cavity, at the 1/4" output, all I got was around 8.85 VDC which of course is just the battery voltage. If that is all there should be then all is fine there. Mica, should I have found another voltage to test in the Orion, or is the battery voltage all there should be? If I missed the point of what to look for, please tell me exactly where to test and what I should or should not find. Then, this weekend I'll have my guy check it out in a more knowledgeable and equipped manner when he tests the Mesa 400+ output too. Mica and a few others have suggested I play with the gain pot in the Orion cavity. Although I had done so before, I tried again last night. I found that just like when I lowered the pickup, I got a slightly higher audible volume before distortion. A little improvement is better than none and I'm glad I went back and tried that again. The pot is now nearly at its lowest gain setting. In addition I also followed up on another suggestion involving use of the effects loop and playing with the loop blend control. It made no difference. Thanks you guys for the specs of your rigs. This info will come in very handy, I have the feeling. Also, Gary -- I might be getting rid of my two 1X15" Mesa/Boogie RoadReady cases with their original EV 400W speakers (just newly rebuilt by Heavy Custom Electronics, in Brooklyn), depending on whether I decide to go to other cab(s). You might downsize; I might upsize. I am in southern PA; before you make a decision on that, let me know if you wish to discuss my implication outside of this forum. LoharTu, sounds like you had a good experience that night you used someone's Mesa rig! It seems the only difference between that setup and mine is that that setup had more cab space (one 2X15" rather than two 1X15"). Hmm. Sorta corresponds to what I am suspecting. More shall be revealed with my upcoming lab tests. Cntrabssn, regarding your question: the Input Gain controls the preamp side of affairs, which also is adjusted using the tone pots on the Mesa head's front panel. The Master Volume controls the power amp side of affairs, which also is adjusted by the graphic EQ on the front panel. I have worked rather extensively at attaining output volume using these two power controls in varying manners, including the manner in which you suggested. With respect to these two controls, the situation seems as broad as long, so to speak. (What I note is that the sound falls apart a bit -- independently of the distortion issue in this thread here -- if the Master setting is less than the Gain setting.) Gary, let me get clear on one thing you said. You have your Mesa 400+ graphic set flat? Or switched off? And your three pull pots are pushed in (Gain, Treble, and Bass? I take it that you meant those when you said you use none of the boosts. Thanks everybody, once again. I look forward to further communication over the matter. All the while I will keep posting my tests and results, and shortwith might seek more discourse regarding alternative gear. Turk | ||
| gare
Intermediate Member Username: gare Post Number: 113 Registered: 11-2003 |
Turk Thats correct, all the boosts are pushed in, the graphic is shut off. You may want to take your voltage readings from the end of a cord plugged into the instrument, thats what the amp would be seeing. Your reading sounds as if its only the battery rather than the output of the circutry. Just thinking out loud..do you place the head on top of the speakers cabs ? Does the distortion only occur at the lowest notes ? You may want to isolate the amp from the cabs and eliminate vibration, you may have a loose wire or component inside. I'd have a qualified tech check out the circutry..you dont want to be messing around with the high voltages in there..unless of course you like curly hair. Seriously, it could really wreck your day getting zapped. Careful now ! G | ||
| cntrabssn
Junior Username: cntrabssn Post Number: 31 Registered: 6-2002 |
Turk, Someone else mentioned trying to isolate the problem to the pre or power amp sections. Did you have any luck trying this? For example, if you plug your bass into the effect return, you'll just be using the power amp section including the master volume and graphic EQ. I'd like to know if the sound gets cleaner this way. And as suggested earlier, you could try listening to your effect send output with headphones (master at zero) or use it to drive another amp if one is available. - nate. | ||
| turk713
New Username: turk713 Post Number: 8 Registered: 1-2004 |
Hi Gary and Nate, Gary, yes it appears that I got only the battery reading in the cavity. I had also tried the cable end as you suggest and I got nothing. Although I used to know significantly more about simple electrical testing, perhaps I'm now not doing it correctly. I'll try again with the cable end tonight. Regarding head vs. cab placement, Gary, I have tried with various placements. I have even had the amp indoors while the cabs were outdoors, and I just used long cables (heavy 12 guage for the speakers, and a couple different brandnames for the bass). The amp was away from the cabs, and the cabs were away from all environmental structural vibration. Your cautionary remark is noted and appreciated. The guy who will be testing my stuff this weekend is the technical services manager for ElectroHarmonix & Sovtek. He'll know how to go about it, or it's his hair and not mine! Nate, I have not yet tried the Orion output gain all the way down yet, as you suggested I do. I have it down to about 20% - 25% Wouldn't lowering it to its minimum setting just mean I am running passive rather than active? Regardless, I will try it out tonight as a test. About the effects return, yes I plugged straight into it, and again I got the same distortion when I got up to around the same audible volume as before. Of course that required going rather high on Master Volume. I haven't tried the headphones idea yet. I will try it tonight. I will also see about coming out of the effects send and into the return on another amp. Thnx again, and more to come. Turk | ||
| bsee
Senior Member Username: bsee Post Number: 583 Registered: 3-2004 |
Not to state the obvious but... You did play notes with the volume up while you were testing voltage through the cable, right? Otherwise, your non-reading would just be proof of how quiet Alembic electronics can be. | ||
| cntrabssn
Junior Username: cntrabssn Post Number: 32 Registered: 6-2002 |
Turk, Reducing the gain trimmer to it's minimum setting does not mean you're running passive. You're just reducing the internal preamp gain. Anyway based on the effects return test, I'm thinking that you need to focus on the amplifier. By using the effects return as an input, you're taking most (if not all) of the Mesa's preamp out of the signal path. We can't say that the bass is too hot anymore, because you had to turn up the master a lot higher to get the distortion. If you run the headphone test with the effects send I think you'll find that the signal is clean there. Perhaps now you can focus on what's left; the graphic EQ, the master volume (which basically controls the power amp input sensitivity), the power amp, and speakers. I'm not sure if the graphic EQ is before or after the master volume. You did say that the graphic was shut off, so I'm not sure that's a factor now. Perhaps you can double check. You are using the proper output tap(s) for you speaker(s), right? At this point, I would continue to test plugged into the effects return. Thanks, - nate. | ||
| dfung60
Junior Username: dfung60 Post Number: 47 Registered: 5-2002 |
Turk - You've had a couple of good recommendations here already. It sounds like the output level from your Alembic is higher than the Boogie wants. I have a Bass 400+ as well and don't find that it's overly prone to overdrive, but it is more sensitive than most of the popular solid state amps (SWR, Trace, etc.). You mentioned that your bass sounds "fuller" than other basses when you plug it into another amp. Your ear will normally equate "louder" to "better" until you have a chance to listen past the volume difference and hear the tone. You may need to back the Alembic output level to a point where that volume difference no longer exists. At that point, you'll have a clean signal and will have a better chance of really comparing the tone. A bass with active electronics has a powered (therefore "active") preamp between the pickups and the output jack. The preamp provides a buffering effect that prevents the electrical characteristics of the cable from affecting your tone. With a passive bass, you'll experience a loss of treble even with a cable of moderate length as the capacitance of the cable's conductors and shield begin to approach that of the tone cap in your instrument. And you'll hear a huge effect on your tone if you turn the instrument volume down. As the cable gets really long (100'+ snake-type lengths, much longer than you'd use), you'll also suffer a reduction in overall volume and in the bass frequencies. With the active preamp buffering the signal between pickups and amp, you'll get the full highs and much less tone change as you roll the volume down. Even if you turned the internal gain trimpot down to even lower output than a passive bass, you'd still have all the benefits of the active circuit. I'm not certain about how the Alembic circuit is designed - the internal trimpot may be in serial with the volume knob on your bass in which case they have exactly the same effect. Alternatively, the trimpot may be out of the audio circuit and may control the gain of the preamp. If this is the case (factory folks, chime in here!), then there may be some tonal differences between using the volume knob and the trimpot. The net result is that you don't have to tweak the trimpot to check whether levels are the problem. Just turn down the volume and see if the problems go away. I think you'll find that they do. If you read 8.85V DC on the battery, then you might consider changing it. A fresh battery will read over 9V. This one isn't too bad, but a fresh battery would be best for this debugging. As the battery level decreases, you will progressively lose headroom on the internal preamp. To read the output level, you need to set your voltmeter to read AC voltages, then connect the test probes to the hot and ground of your bass' output jack. Because this is AC, positive and negative (red and black probes, usually) don't matter. You don't need to take your back cover off to do this, just plug in a cord normally and hold the probes against the tip and sleeve of the other end of the cable (obviously, you won't be plugged into the amp!). Hit a note, maybe an open A or open E. The voltage it stabilizes at will be the approximate RMS output voltage level of your bass. With instruments close at hand, I read 0.08V for a passive Fender P-bass, about 0.11V for and EMG-equipped Modulus, and 0.32 for a Series I Alembic on batteries. The EMGs would already be considered "hot" relative to a passive bass, and my Series I is 3x that level. That's a +6dB setting which would definitely cause overload on a sensitive input. I have the gain trims set moderately low on this Series I, but the output level is lower with the external power supply which I normally use vs. the batteries that I used for this test. At this level, I would definitely have had overdrive problems with my wireless transmitter. The typical output level of a standalone preamp would probably be in the 1.0-3.0V range. With a Series bass, you can approach the 1.0V range when the trimpots are cranked and drive a power amp directly, although probably not to full power. With a solid state amp, the 0.3V output would be noticably louder and probably too hot without turning down at the instrument. In the Boogie, you'd be pushing it pretty hard. I didn't realize I was cranked quite this far and would probably back off to less than 0.2V to make it easier to switch instruments. I would definitely look at backing that output level off significantly and see if that fixes the problem. If you overdrive the preamp stages of the Boogie, it won't really get any louder that if you were feeding it a signal at the proper level, but it will sound bad. Finally, I would try testing some other basses through your rig to see if there's really a problem there. An EMG or other active pickup bass would be the best test by far. Good luck, David Fung | ||
| bigredbass
Advanced Member Username: bigredbass Post Number: 352 Registered: 9-2002 |
Turk: Bass 400s have lots of tubes, are you sure about them, particularly your input section tubes? More to the point, have you talked to MESA themselves? In my experience they are REALLY committed to happy customers. J o e y | ||
| turk713
New Username: turk713 Post Number: 9 Registered: 1-2004 |
Hi all, Following this weekend I'll reply to the last posts, plus I'll then have had lab tests done on the Mesa pre and power amp outputs plus that of the Orion. G'weekend, Turk | ||
| turk713
New Username: turk713 Post Number: 10 Registered: 1-2004 |
Hi folks, Well, this past weekend yielded nothing I wanted to yield. I got buffooned by the ElectroHarmonix guy. He wrote down no readings for me, contrary to my orders to do so and to which he consented. In addition, he changed the tubes for another kind and changed a preamp tube for another kind. I got home and tried things out and within two minutes my amp crackled and shut all the way off and won't turn back on. By now I am out of the picture, guys. This is too much, too long, and I find that I can trust techs anymore. So thank you for your help. Unfortunately, I have no info that will help you help me further, and I have a whole new problem. I cannot afford this anymore. I might quit playing altogether. I no longer enjoy it, and I play in fear that something will go wrong, and certainly it is way too costly by now. I do not know how long it would take me to get over all that even if suddenly all was well. I don't know what I will do now. Even if it's just the fuse, I will always wonder what caused it to blow and when it will happen again, and I will always wonder what else will happen without a moments notice, due to whatever is really going on, and due to not knowing exactly what this guy did and did not do. Maybe I need tons of encouragement; I don't know. Turk | ||
| turk713
Junior Username: turk713 Post Number: 11 Registered: 1-2004 |
CORRECTION to my last post: the last sentence of the 1st paragraph should read "...can't trust..." rather than "...can trust...." Turk | ||
| locutusofborg10
Member Username: locutusofborg10 Post Number: 54 Registered: 11-2002 |
just an idea...when and if you get your amp working again sell it to someone who plays a fender...what do they know anyway...don't give up, though. if you ever make it into NYC look up jeff bloch's amp and guitar wellness center in brooklyn, he'll get it right. he's been doing it for me for over 30 years. if you want the number e-mail me and i'll be happy to give it to you. | ||
| dnburgess
Advanced Member Username: dnburgess Post Number: 349 Registered: 1-2003 |
It might be a bit late to chime in here - but I took a bunch of Alembics to a dealer and played them all through his Mesa 400+ (into an Acme B2) and they all sounded great. Admittedly that was at shop volume, not gig volume. David B. | ||
| gare
Intermediate Member Username: gare Post Number: 114 Registered: 11-2003 |
Turk OWWWW..He replaced all 12 power tubes ? And the pre-amp tubes ? Plus his service charges ? Sorry to hear this is getting worse, it can be very frustrating and depressing. But I wouldn't give up just yet. Before you stick another fuse in..you may want to take a peek in there and see that all the tubes are properly seated (with power off of course), and see if there are any charred parts. I would also contact Mesa's service department and see what they now recommend for the new problem, they may also be able to recommend someone near you thats aurthorized to service their products. Before the amp went out, how did it sound ? Any better ? Seems a shame to give up on the amp,unless of course there's some hidden major problem. Good luck..and have a great holiday ! Gary | ||
| dfung60
Junior Username: dfung60 Post Number: 48 Registered: 5-2002 |
Turk - I'm sorry to hear that you experienced "bad tech" disease. The sad reality of the world is that diagnosis and repair (of anything really) is an art and that there are very few artists around. I have a lot of high-tech electronics around home and I really cringe when I know something isn't right. Replacement would be expensive; trying to get it fixed, probably "too" expensive and unlikely to really solve the problem. :-( The good part about your rig is that it couldn't have been better designed or built when it came from the factory. The bad part is that it's probably an order of magnitude more complicated to work on than most solid state amps, and that fact that it's filled with vacuum tubes makes it really expensive to work with as well. Under normal wear, it's possible that it could be all the tubes just getting old. For that (the "tired amp" syndrome), replacement of tubes (about 18 or so if I remember correctly for the Bass 400+) is the right place to start. But when you get a catastrophic failure it's more likely that another component, perhaps a cap or even a resistor has failed. This throws the amp circuit out of whack, gets you weird distortion and non-linear response, and ends up frying some of your tubes. A tech that's not experienced with working with this amp may only see the fried tubes and hope that replacing them will fix the problem. All that will happen is that it will repeat, as appears to be your case. Even an amp tech that works on Marshalls and Fenders will be scratching his head with the Bass 400+. Guitars amps are a lot simpler - 2 or 4 output tubes in the power section instead of 12 that need to be carefully matched. To set bias and get the tubes working properly, they need a suitable speaker simulator or load (tube amps have no output with no load). If you use a Power Soak for Marshalls, your Boogie will reduce that to a pile of smoking carbon before it's even coming close to stress. I've got old SVTs as well. I love the sound and can tolerate the weight, but getting it worked on is a nightmare - lots of otherwise talented people say they can work on it, but results have been pretty spotty. If a component in the power amp got cooked, the bias of the output circuit may be off. The tube associated with this part of the circuit may operate cold (which gives early distortion) or too hot (which gives a different kind of distortion and causes the tube to fail more quickly). The tube will test bad after being in this environment, but putting a new tube in will just kill it again. The tech needs to test for this problem individually on each tube. You may also be aware that Boogie amps don't have adjustable bias. In a Marshall, when you have a partial component failure, the bias voltage may shift, but you may be able to adjust a trimpot to fix the problem, at least temporarily. No dice on the Boogie. They have a proper bias voltage that the tech can measure for, but to prevent your needing to have a highly competent amp tech, Boogie made the decision a long time ago to set a fixed bias voltage, tell everybody what it was, and require you to buy tubes that were pre-tested to operate properly at that voltage. If you have the "wrong" tubes, it won't work optimally just plugging new tubes in. Old tubes could tolerate a higher bias voltage than new ones, too. A good amp tech will confirm the performance of the circuit, use the right tubes, or can make the adjustment to the circuit to adjust the bias if necessary (generally, this requires substituting a big huge resistor for each power tube). Since this last fix was clearly a boner, the tech needs to live up to his screw up. Asking him to fix it more when he doesn't know how to probably won't help (make sure that your work wasn't done by somebody else in the shop first). If they can't get it fixed properly, ask for your money back. If they won't do that (grrr, all those tubes), then see if you can at least get your labor back. Find somebody else and get it fixed right - it sounds like your in NYC, so you have a better chance than most to find somebody good. If that doesn't work, send it to Boogie. Unlike most amps out there, this one is probably worth it if it's not something really catastrophic inside. One other piece of advice... If you have to drive to work everyday, it would probably work best if your only car wasn't a Porsche. Perhaps a bland but super-reliable solid state amp would be a good gear addition, if for no reason other than a backup amp. I pick Porsche intentionally for comparison. I've owned a couple including one now. They are really well engineered and really well built, as well as being sublimely sporty. When things are good, you really can drive them every day without worry. But when they break, you can expect so not see it for a while and it's going to cost a lot of money to get back. So, you just need to balance whether this is the right amp to depend on. Best of luck, and never give up. | ||
| lbpesq
Intermediate Member Username: lbpesq Post Number: 200 Registered: 7-2004 |
Turk: If you had a problem with your Alembic, would you contact the local tech advertising on Craig's list, or the folks in Santa Rosa? Same thing here. Contact Mesa. I've played through a Boogie for 18+ years. On the few occasions where I've had a problem, a question, or desired a modification, they were EXTREMELY helpful. I think the Mesa people must have graduated from the same business school as the Wickershams. I know it can get very frustrating, but don't give up playing! Take a moment. Breath in. Breath out. Let it go. Happy Festivus Everyone! Bill, tgo | ||
| jacko
Member Username: jacko Post Number: 80 Registered: 10-2002 |
Turk. Surely the work carried out by the tech will be covered by some sort of warranty. Don't know how it works in the US but in the UK we have a trading standards organisation to look after the rights of the consumer in such cases. At the very least you should aim to get enough in damages to have the amp properly repaired by Mesa. graeme | ||
| turk713
Junior Username: turk713 Post Number: 12 Registered: 1-2004 |
Hi again gang, It feel quite supported after reading all of your most recent posts. Thank you. It sure helps. To answer a couple actual and potential questions here, the fuse looked perfect when I checked it immediately upon the noisy shutdown I have described. It looked intact, centered, and clean. Also, the noise that occurred with the event did not come from the amp's direction; it came from the speakers. This indicates to me, in general, that indeed the cause was in the signal path, and not just in the amp's power supply path. But then, I do not know what circuits have common components. The recent work was not done in a formal company lab. It was done privately at the home of a highly recommended tech manager for ElectroHarmonix/Sovtek. He claims to have a personal warranty he adheres to. I do not know its terms. I know this though, that his professional reputation could be put on the line if I were to call ElectroHarmonix and they thought I had legitimate complaint. He would be out of business at the private level, and could lose his good career at ElectroHarmonix. I doubt he meant mischief, but I have strongly suggested to him that he give me back some money. Yes, the amp sounded quite different during the two or less minutes that it did work before it shutdown. The guy who replaced the tubes told me he was getting a lot more power without distortion. I think he may have been correct on that. I actually felt that I could take the rig and play a venue with no PA and do okay, for a refreshing change! But I made no conclusions; too early. At the same time, I preliminarily noted this following, something about the new power remotely impressed upon me the idea that this difference was a bit much for the rig to handle without a problem. I can't describe this impression any further. And then...snap crackle pop. The tubes he put in were made by his company --no problem in that. And for goodness sakes I figured that if anybody knows tubes it would be him! Exactly what he put in were the following. He replaced the 12 existing power tubes (I forget the name; they were 6L6's and had a brand logo that amounted to a C with a circle around it) with Svetlana SV6L6GC tubes with an IP of 44, and a GM of 5,200, whatever that is. These are structurally different than the 6L6's that were in there, at least insofar as the new ones' internal parts (anode, etc.) are mounted in the tubes with little springs at top AND at the bottom inside the tubes) to reduce the tendency of the working parts of the tubes to vibrate from ambient sound vibrations in the room, and thereby reducing the tendency for the tubes themselves to make a distorted sound (a phenomena called microphonics). Additionally, he replaced only the first preamp tube that the signal reaches in the head. He put in a Sovtek 5751. This tube apparently does a superior job at cleaning up the incoming signal. So it too was meant to be an anti-distortion measure. locutusofborg10, yes please give me the number for Jeff Bloch's in Brooklyn. I want it as a resource for the future, certainly. However, if I get my mind and available cash together here, I will no doubt just send the amp across the country to Mesa, this time. They too are trying to help me, as are all you good people, and of course as are the Wickershams. I will not give up, although I have very seriously considered it. It seems that we who do play, must play, lest our angst grow to monstrous size. Thank you all again. And let's pick up with this issue later when there exists more content to discuss. I will write at that time. Hope you will still be tuned in then. That is, unless anybody has more for me right now.... Happy Holidays! Turk | ||
| lothartu
Member Username: lothartu Post Number: 83 Registered: 8-2003 |
Best of luck Turk. I'm sure that myself and others will be keeping an eye out for your next update. Everyone that plays has gone a few rounds of "what's up with my equipment", some worse than others. Everyone here wants to help because we've all been there before and we know how frustrating it can be. Hang in there and keep us posted. As usual I'm sure everyone in the club will do whatever we can to help. Have a happy holiday and look on the bright side... you own an Alembic.  - Jim | ||
| turk713
Junior Username: turk713 Post Number: 13 Registered: 1-2004 |
Just keeping the thread alive here today. Thanks Jim.........A good year to all. I will take my Mesa to my guy in Brooklyn and let him correct the immediate problem. From that point, then, I will get back into the original situation we've been discussing here. I suspect it could be a couple weeks yet before I get to that point. I will post then. Turk |
