| Author | Message | ||||
| ronrogue
New Username: ronrogue Post Number: 1 Registered: 10-2012 |
I picked up a '96 Rogue 5 about a year ago that was clearly mothballed for a while, but belonged to someone who played it like his workingman's. I've had a problem with the ambient sound of the bass when I plug into several larger type amps: 400 watts+ that are turned up to a relatively loud volume. I assume that if you plug a bass into an amp it will be relatively quiet if you're not playing, but my rogue 5 is not that quiet. I can flip the switches and get a whirling sound at higher and higher pitches. Also, when I play for over 30 minutes, the bass sound becomes more and more muffled over time. Then I need to drop it and plug in my other bass that's 10 years older to continue playing with the boys. I've experienced this on several amps in different settings and locations. So far, I've changed the jack, and got an RF Upgrade from Alebmic.The wiring has been double checked for shorts as well. But nothing has worked. Any suggestions for getting the gem I have to shine again ? Ron | ||||
| serialnumber12
Senior Member Username: serialnumber12 Post Number: 1003 Registered: 12-2004 |
Battery? | ||||
| lmiwa
Advanced Member Username: lmiwa Post Number: 334 Registered: 2-2008 |
It definitely sounds like a power problem. If the battery itself is good, there may be an issue with the either the jack or the plug you are using to turn on the electronics. I'm assuming you don't leave the cable plugged into the bass when you're not playing. Does the volume control have any effect on the noise that you're hearing? If you pull the battery out, do you still get noise or is it then completely silent? | ||||
| ronrogue
New Username: ronrogue Post Number: 2 Registered: 10-2012 |
I've replaced the battery a few times, and I always pull the chord out after use as not to drain it. If you pull the battery out, there's no noise. With a fresh battery, I tried again... It would appear that if the filter knob is turned all the way clock-wise, I get a low whirl. If I flip the Q-switch to the up position I get a higher pitch louder whirl; and then flip the trebble cut/flat/boost switch all the way down, I get an even louder whirl. The bass switch doesn't have an effect in any position. The volume and pan do not have an effect other than the whirl being louder or lower from the volume. Your feedback is very much appreciated. Ron | ||||
| lmiwa
Advanced Member Username: lmiwa Post Number: 335 Registered: 2-2008 |
Sounds like some kind of HF interference. The actions that you are describing that increase the noise, are the ones that boost the higher frequencies. Also, since the pan has no effect, it is highly unlikely that it is being generated by one of the pickups (they would both have to be picking it up exactly equally). So it is either a component failure in the preamp section, or noise is getting picked up after the pan pot. Not sure if you can post a sample file here, but maybe if we could hear the noise, we would have a better chance of identifying the souce? Also, from your initial description, it sounds like you've tried different amps, different cords, and different locations, so it seems unlikely that an external source is creating the noise - flourscent lamps, cell phone, etc. Have you tried running your bass straight into a recording device (USB interface, direct box, etc)? | ||||
| ronrogue
New Username: ronrogue Post Number: 3 Registered: 10-2012 |
It would appear that the pan does have an impact. When I pan towards the bridge, I get more noise than center. I've attached some .amr files to give a sense of the sounds.
| ||||
| count
Member Username: count Post Number: 66 Registered: 10-2003 |
Wow! That's does NOT sounds normal.  I also have a problem with my Rogue5 (1997) dulling out after a good hour of playing time. Usually improves after I change the battery though. However, it does NOT have the ultraviolence soundtrack that your bass has.. Hope you figure out what it is man, that can't be any pleasant.. Btw, rightclick on the attachments, download them, and open in VLC. | ||||
| lmiwa
Advanced Member Username: lmiwa Post Number: 336 Registered: 2-2008 |
OK, that's definitely a 60Hz line hum! Usually caused by an open ground somewhere. It doesn't sound like it's actually coming from the pickups. I think there are separate gain controls for the pickups so that the pan is balanced, so that may be what is causing the difference in hum levels. You might try swapping the connectors coming from the pickups to the preamp. In fact you may want to try disconnecting them entirely and see if the hum goes away. I don't think the pickups themselves are grounded, so that probably isn't the issue. I can't remember how the shielding is grounded, but there may be an issue there. Is your other bass a passive bass? If so, can you borrow another active bass from someone just to make sure you amp system doesn't have an issue with active basses in general. (I seriously doubt this is the issue, but it's worth checking) In any case, your bass absolutely should not sound like this - there is a problem somewhere. The two rogues I had were both dead silent even in an environment with flourscent bulbs everywhere! | ||||
| terrace
Junior Username: terrace Post Number: 43 Registered: 3-2008 |
Check if the input jack is tight and making a good connection with the shielding paint.Mine periodicity loosens. | ||||
| ronrogue
New Username: ronrogue Post Number: 4 Registered: 10-2012 |
My other bass is active, and the jack seems tight. It also sounds like I have the "dulling out after a good hour of playing time" problem, but first the ultraviolence problem... I've attached a picture of the wiring. Forgive my stupidity, but are the two gray wires from the north side of the picture the pickup wires to the pre-amp?  | ||||
| dfung60
Senior Member Username: dfung60 Post Number: 568 Registered: 5-2002 |
There's no stupid questions in the electronics cavity of an Alembic! You definitely have a grounding problem here, which is worse on the bridge pickup. The pickup leads are the two gray colored wire bundles that are coming in from the hole on the "top" of the cavity. They are looped together through a ferrite bead (this helps kill off high frequency RFI noise, then each lead goes off to a separate connector which is plugged into the main EQ board. The pickup connectors are the two brown colored plugs on the EQ board next to the bright blue trimpots. If you gently unplug these connectors, you can disconnect or reverse the pickups on the pan pot. I think the other wire coming into the cavity must be the power supply from the battery, also coming through a ferrite. Turn the volume on your amp down to a low level before you do anything in the compartment. You can generate large transient pulses when you disconnect or connect things, and you don't want to damage your amp. The first thing I'd do is gently wiggle everything in the compartment to see if you can isolate the source of the hum. Everything in the audio path can potentially pick up hum from the outside world. The way that guitars prevent this is to build a cage around the audio path and connect that to electrical ground. Any noise that's picked up is then sent to ground without getting into the circuit. The pickups are designed to pick up noise, but they have a special coil inside the pickup that eliminates much of that noise. The inside of the compartment is coated with conductive paint, so it shields a lot of the electronics. Things that poke through the compartment like the pots, jack, and switches have their cases intentionally grounded so they act as part of the shield as well. The problem with your bass is that there's something that's become disconnected from this network of shielding. Instead of blocking noise, it's picking noise up and injecting it into the audio. The first thing I'd try is to gently wiggle the red pickup connectors and the other red plugs in the compartment. I'm pretty sure the red plug in the bottom left of the picture is power, so you can wiggle that one, but don't unplug it while your bass is plugged into the amp (you'll get an enormous boom if you unplug it). Next I'd gently wiggle the ferrites, the board, the jacks, and pots and the back side of the switches. You don't want to force anything at all, just a gentle bump. If there's a failed connection somewhere, when you jiggle the parts, you may reestablish the connection and the hum will go away. The three things I'd really suspect here are the pickup plugs - one may have become intermittent or that the ferrite beads may be touching something that should have been insulated. The third thing is to see if the output jack has lost contact with the shield (unlike most of the stuff in the cavity, the output jack can get stressed from the outside world). I would also unplug each pickup individually and see if the problem goes away (of course, one of the pickups will go away too). One other things that's very unlikely, but easy to do... Wrap your battery with electrical tape. I doubt that the battery compartment is painted with silver paint, but if it is, grounding or not grounding the metal case of the battery can be an issue. Try this stuff and report back! David Fung | ||||
| lmiwa
Advanced Member Username: lmiwa Post Number: 337 Registered: 2-2008 |
Also try lifting that big ferrite tube in the middle just to make sure it isn't shorting/grounding something out below it. | ||||
| xlrogue6
Advanced Member Username: xlrogue6 Post Number: 231 Registered: 8-2002 |
The output jack is suspect number one--deep panel 1/4" jacks have a fairly short service life if they're not babied (as in, always use a right angle plug and loop the cable through the strap). If the problem goes away when you move the plug in the jack *just so*, that's your problem. Also, given that the bass was out of service for a while, oxidation of the jack contacts (and, for that matter, the Molex connectors) is a distinct possibility. A can of DeOxit is never a bad investment... | ||||
| ronrogue
New Username: ronrogue Post Number: 5 Registered: 10-2012 |
I disconnected the pickups one at a time. With both out, there is no noise, but reversed, and one or the other in, there was noise. I must have reconnected something after jiggling the various connectors, ferrites, board, jack and pots, and it would appear that the noise was reduced, but there is still a hint of interference, but I couldn't reproduce the nasty noise I had before. I'll replace the battery and strings and give it a go and test for the dimming sound. Thanks for the help. | ||||
| dfung60
Senior Member Username: dfung60 Post Number: 569 Registered: 5-2002 |
Interesting results. If it was quiet then both pickups were unplugged, then this probably means the stuff in the electronics compartment is OK. I would first suspect one of the pickup connectors has a problem (it won't be visible, but the shield conductor connection may be loose). But the chances of both connectors having a problem is extremely low unless there was some significant manipulation going on. To diagnose this, plug just one pickup into it's normal socket, then into the other. Do the same thing with just the other pickup (in both sockets). If you hear noise coming from just one pickup, I would suspect that pickup. If you hear noise coming from just one socket, then the problem is in the EQ board. If, as you describe, you hear noise from both pickups in both sockets with one or both pickups plugged in, then you've got a EMI problem in this location. Too much airborne electronic noise and no bass can reject it. But it's pretty unusual to have such strong EMI that sounds like 60Hz hum. David Fung | ||||
| lmiwa
Advanced Member Username: lmiwa Post Number: 338 Registered: 2-2008 |
Unless you're standing right in the middle of a power station, it shouldn't sound like that if everything is working correctly! Also, if it's an environment issue, you can change the quality and intensity of the interference by turning the bass in different directions. If it doesn't change, then it's an internal issue. | ||||
| ronrogue
New Username: ronrogue Post Number: 6 Registered: 10-2012 |
Thanks for the help before, and now that the bass has nice tone, I am still having an issue where the bass goes out at times. I was playing this weekend with a fresh battery, and I was able to reproduce this in the afternoon and then again later that night. After about 20 to 30 minutes of playing, the rogue cut out. If I unplug the cable to the bass, and plug it in quickly, I get sound again. I've looked at the wires on the plug and they appear attached ok. I've been able to do this with different cables as well. Any ideas what might be the cause of the rogue cutting out? Ron | ||||
| xlrogue6
Advanced Member Username: xlrogue6 Post Number: 247 Registered: 8-2002 |
Change the output jack. If your cable has Neutrik plug on it you might want to try one with a Switchcraft. I've have some weird issues with Neutrik 1/4 plugs (particularly right angle ones) lately. If jack replacement doesn't solve the problem, there may be a solder joint issue elsewhere in the electronics. | ||||
| ronrogue
New Username: ronrogue Post Number: 7 Registered: 10-2012 |
I had the output jack changed, and I thought I had it working, but last night at practice it cut out on me again. I was able to get back sound by unplugging and then replugging in the cable quickly. Any other suggestions ? Does it pay to just swap out the entire electronics ? | ||||
| gtrguy
Senior Member Username: gtrguy Post Number: 588 Registered: 9-2004 |
No, it sounds like you have something fairly simple wrong, though it seems complicated to figure out what it is. Maybe a bad battery connection? They are easy enough to replace. | ||||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1427 Registered: 5-2006 |
Is that the original board position? The picture in the faq shows a different position: http://alembic.com/club/messages/16271/24781.html At the top resistor (in your picture under the top blue trimpot) it looks like there's some metal part coming extremely close to the cavity shielding (silver paint) Make sure none of the metal parts are touching the paint. (the beads are non conductive, so no worries there) | ||||
| ronrogue
New Username: ronrogue Post Number: 8 Registered: 10-2012 |
Thank you all very much for your input and guidance. I learned a lot about the bass. I ended up replacing all the electronics including the jack. (left the pickups) I even changed the knobs. Thanks Micah! The bass is now amazing! I've been playing it over the past few weeks, and finally gigged with it this weekend with no issues in sight. ronrogue is now ronhappy |
noise example