| Author | Message | ||
| jazzyvee
Senior Member Username: jazzyvee Post Number: 1174 Registered: 6-2002 |
I had a gig tonight in a medum size pub and too my Europa 5 bass, 4x10Mesa Boogie powerhouse cab, SC poweramp, F1-x and sf-2 to the gig. There was no PA on the venue except the vocals. Now my sound I was not happy with at all. When I stood close to the cab the sound was nice and heavy and with all the clarity i needed at the top end too. But once I moved may be 10 feet or so away from it , there was no weight in the bottom end of the sound it was just thin. Any ideas how I can beef it up without having to carry loads of boxes on small gigs I have a 2x10 and a1x15 cab if that helps. I did hear before tha tmesa cabs don't throw out much bottom end when you get further from it Even with the SF-2 I could only get a good sound for me in fromt of the cabs but not out in the room. | ||
| ralphl
Junior Username: ralphl Post Number: 20 Registered: 4-2008 |
There are a bunch of possibilities. Did you ask audience members in the club about your sound? 4X10 cabs are generally a short throw cabinet but that does not mean the bass wave was NOT developing further off stage than you ventured while playing. As well, lots of people in a club absorb bass frequencies. Depending on the club's design, the bass might have been getting to the audience but not much reverberated back to you. Did you try cranking it up? Occasionally, especially outside, I have your experience and I just slowly start to turn up. When the other guys start giving me the eye, I turn down just a dash. Did you try adding more of the mid-range frequencies? That can help sometimes when you loose your bass sound on stage. I have never heard of a SC power amp (Do you mean QSC? Prolly, eh?), but gain structure can be another issue. I've occasionally inadvertently turned a knob on my preamp (and you have 2 preamps!...lucky guy!) that caused problems. I once flipped a cross-over switch and was only getting frequencies from about 120HZ and above. Sounded great right next to the cabinet but the crowd was unimpressed. Took the sound man's knowledgeable bitching and 2 sets to find the trouble. Ultimately, the real issue is your balance with the other players in non-PA situations, especially the drums. Could you have been burying them as it was and getting louder would have been imbalanced? Tough to say because you were not 20 feet out in front of the band. Ah, "The Wall of Sound" was/is such a great idea. I hope some of this helps. | ||
| keurosix
Advanced Member Username: keurosix Post Number: 304 Registered: 10-2005 |
Hey JV, From what I can remember this sounds like a question of cabinet design, among other things. A Bass reflex design only pushes lower frequencies a short distance in front. A horn load design pushes it much farther so it reaches the audience, but sometimes past the stage so you never get the full sound. Without replacing cabs, I think you can explore cabinet placement and specific EQ with your preamps to target certain frequencies. Someone else should be along with more technical help too? Kris | ||
| jazzyvee
Senior Member Username: jazzyvee Post Number: 1175 Registered: 6-2002 |
Well, this was a pub so when i say stage it means an area of the floor so I was at the same level as the audience. I have a 30ft lead that I usually carry as a spare so I can walk out front and check my sound. And at that distance there was mainly mid range and top end. no weight. Considering we were doing some reggae numbers a weighty bottom end is really essential. This was before the audience were let in the room. I asked the singer to go to into the hall and get some feel of the bass. He said it was light too. | ||
| byoung
Senior Member Username: byoung Post Number: 1037 Registered: 12-2004 |
Are you still using the crossover on the F1-X? I'd start by running both cabs full-range if so. Other than that, some things to check: 1) cab placement putting the cabinet in a corner or near a wall will provide a bass boost. 2) casters If you have casters, take them off and try it. 3) vertical stacking Try to have all your drivers (especially the woofers) align vertically-- this will help prevent horizontal comb-filtering. This means that the 2x10 should be vertical, and on top of the 15 (and the speakers should line up on center). Bradley | ||
| ralphl
Junior Username: ralphl Post Number: 21 Registered: 4-2008 |
Since you say you were using a single cabinet and there were no other speakers duplicating what you were playing, then phase is probably not an issue. Regardless of cabinet "throw," a fundamental bass frequency "looks" the same; a 100 HZ wave is always 11.5 feet long. Your cabinet is either reproducing the wave or it is not, regardless of upper range frequencies like mid-range, harmonics, etc. If you do not hear bass frequencies 20 feet away, then I'd try turning up bass frequencies at the preamp. Add more bass to your signal in one way or another. | ||
| dfung60
Advanced Member Username: dfung60 Post Number: 331 Registered: 5-2002 |
When you aren't being reinforced into the room via the PA, this is often going to be a problem. The only way to solve it is more speakers to move more air and a lot of power to drive them (unless you have a very small power amp, this probably won't be the problem). Actually, the people in the room absorb the highs more than the lows (that unbelievably annoying crash cymbal that you're standing next to doesn't penetrate a room of people at all). But the problem for lows are that you just need to move an enormous amount of air to get the low frequencies happening in the room and it need to be clean too because the sound of your distorted amp will be dominated by the harmonics rather than the fundamentals. A 4x10 cab's driver surface area is about 315 sq in; a 2x12 guitar amp is 226 sq in, but his 100w with 20% distortion (or more) is much louder than your 4x10 with even 1000 watts clean (not that the cabinet can take that much!). If you were able to add a second 4x10, the double surface area gives you another 3dB, but you also get another 3dB from being able to handle twice the power. A +6dB bump is pretty noticeable (+10dB would be perceived as twice as loud). Your 1x15 hasn't quite got as much driver area as a 4x10, but will give you the power bump too. You regularly see the mention about direct firing speakers not throwing as far as horns. From a science standpoint that shouldn't be true, but I've noticed this effect as well (I still have my old Acoustic 370+301). Horn-loaded cabs are much more efficient than direct firing cabinets, but when the speaker in the horn is an 18", there's very little highs and I think that's what makes them hard to hear onstage. Smaller drivers will have less low bass and will tend to be less efficient producing strong lows. The 4x10 "standard" for bass is sort of odd. It comes from being a more manageable half of the original SVT cabinet which had 8x10". It's a great sounding cabinet and is tremendously loud, but not particularly in the low fundamental. It comes from the tube age where it was hard to get enough power behind the really low fundamentals for it to really matter (the SVT head is 300 watts tube power and weighs about 90 lbs, so having 600-1000 watts would be completely unmanageable). Moving more air and adding more power is no different than what you're doing when you're house sound is coming through the PA. They're running more bass bins that you probably have in your stage amp (if only by virtue of there being two stacks), and there's a lot more clean power available. One other thing to try would be to EQ your stage amp such that it sounds good out in the crowd, even if you're way too loud and bassy on stage. You may have enough power and speaker to do this now, even if you risk annoying the rest of the band. You may need to play with the position of your amp to keep from being too annoying. And I pity your drummer who must be suffering with an unamplified bass drum in this environment. David Fung | ||
| ralphl
Junior Username: ralphl Post Number: 22 Registered: 4-2008 |
I made an error in my last post. The physical length of auditory frequencies changes with air density. A 100HZ fundamental varies between 11 and 12 feet due to this fact. This can definitely have an effect on bass sound. This site, http://www.soundstage.com/maxdb/maxdb021999.htm is very helpful and may contain more possibilities for a solution for your problem. | ||
| jazzyvee
Senior Member Username: jazzyvee Post Number: 1177 Registered: 6-2002 |
I did add more bass frequencies with the pre-amo and the sf-2 but all that happened is that where I was on the stage area the bass was very heavy but the cab started to distort when I started to get to a reasonable volume level so I had to back off or risk damaging the speakers. Is this normal for all bass cabs or is it just mesa boogies? I don't do lots of gigs as bass player so i have not built up a lot of on-stage expeience with my sound like I have with my guitar gigs. So I'm really quite lost. Most of my previous gigs on bass have been with a backline and out FOH PA so my cabs have not had to fill the room. I'm not sure what to do next? I can't/don't want to start changing my cabs and spend lots of cash. I just would like a good meaty bass sould similar to what I get when I have the cab in use at home. But in a live scenario in a smallish venue. On guitar gigs, I've never had any problem filling the room with the sound from my fender twin whether its inside, outdoors, miked through PA or stand-alone. Jazzyvee | ||
| ralphl
Junior Username: ralphl Post Number: 27 Registered: 4-2008 |
I'd say the question is: Where in your signal path is the distortion is being created? Is the pre-amp over driving the input of the amplifier? If the amp is being over-driven, then your cabinet will re-produce that, obviously. I would also look at the arrangement of the amp itself. If the amp is of low output, say 150-200 watts, then it is struggling to put out the power you need. That can be another source of distortion. It is not being over driven, but it is clipping when asked to push beyond its limits. Is it a stereo amp? Is it bridged to mono? Does it have an on board cross-over that is active? Are you using a guitar cable as a speaker cable? Don't use a guitar cable as a speaker cord. Use 14 ga.(at least) speaker cables if possible. Be sure the AC power cord on your amp is also at least 14 ga. No starving the amp. If the amp is over driving the cabinet with too much power, then the first thing you need to look at is the resistance of the cabinet (ohms). It should be printed on the jack plate on the cabinet. A 4 ohm cabinet will give more amplitude per watt than an 8 ohm. Two, 8 ohm cabinets look like 4 ohms to the amplifier, so adding another 8 ohm cabinet in this case will help solve the over driven speakers. That is, with the amp in bridged mode, chain the cabinets together, cabling one to another via the jack plate. If it is a 4 ohm cabinet and the amp is not in bridge mode, then try adding one cabinet per side of the amp (the cabinets MUST be of the same resistance! You could also try this with 8 ohm cabinets, if that is what you have). If it is in bridge mode, the amp might be able to handle a 2 ohm load (check the specs) and you could possibly chain two, 4 ohm cabinets together. Be careful when trying these suggestions. Be sure of your settings before firing up the amp! In my experience, Mesa equipment is of good quality. Look at the specs and see what the cabinet is intended to handle. Chances are that the cabinet is not the problem if it is in working order. However, if one of the four speakers is going bad, then the whole cabinet will sound like it is going bad. That might be something to check into also. In the end, once you have looked at all issues, to get more bass you need to move air, as Dave Fung accurately points out in a post above. | ||
| jazzyvee
Senior Member Username: jazzyvee Post Number: 1178 Registered: 6-2002 |
I think the distortion was only because I turned the volume of the amp up a bit too high with a lot of bass dialled in. thats why I backed it off.. I think the amp is about 2400watts into 2ohms so I doubt if it was being overdriven as my cab is 8ohms It was in stereo mode but I was only using the left channel for the output as I was only using one cab. Cables are speakon and I was using the pre-amp with the full range output into the QSC. Cable is the cable that comes with the QSC so i presume it is of the right quality. I guess I'll have to wait for my next gig with it to see what I can do as at home the sound is fine. Plus carrying another speaker cab would be a bit of overkill and I would have thought a 600w cab should be ok to use at a small club sized gig. Jazzyvee | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 701 Registered: 5-2006 |
I think that's your answer ;-) The Mesa 1x15 is a great "stand alone" cab, that's a serious EV speaker in there. The 2x10 (no experience with 4x10 here) lacks bass and I don't like it at all as stand alone cab... Paired with the 1x15 you get more clarity and you hear your bass better. The 1x15 and 2x10 combi is ultimate imho, I think I like it even better than a 1x15 and 4x10 combi. Are you sure the distorted sound isn't the tweeter? They can sound awful at high volume... Though you can turn them off, I've cut the leads and made sure they will never mess up my sound :-) Hope this helps some and sorry for this Mesa veteran to chime in so late ;-) | ||
| keith_h
Senior Member Username: keith_h Post Number: 1013 Registered: 2-2005 |
Just out of curiosity did you try it without the SF-2 in the signal chain? I'm just thinking it would best to start with the simplest signal chain and see how it goes. If it improves then I would think it is just the learning curve associated with using an SF-2 well. As far as horn loaded over reflex cabinets my recollection is the horn loaded cabinets tended to be more efficient and therefore required less power. You then drop into the front loaded horn or "W" box horn, such as the 301. The advantage of the "W" box was, depending upon frequency, a more fully formed wave which let reach full SPL in a shorter distance. Front loaded horns, as I remember, were a little more complicated acoustically since they act like a direct radiator in some instances (higher frequencies) and a horn in other instances (lower frequencies). I don't recall if they took longer to develop a full wave length or not but suspect they do over a "W" box. In either case a horn loaded cabinet is much more complicated to build and quite frequently larger than the equivalent power reflex cabinet. Another thing with reflex cabinets is there is a pretty large roll off below the port tuning. This means a cabinet tuned with a port at 40Hz can sound very week on the B string of a 5 stringer. So this could be related to your problem. Keith | ||
| dfung60
Advanced Member Username: dfung60 Post Number: 332 Registered: 5-2002 |
You should have plenty of power at the power amp. 2400 watts at 2 ohms is roughly equal to 1200 watts at 4 ohms and 600 watts at 8 ohms. The power ratings are usually reflective of an "impending meltdown" level which doesn't reflect real stage conditions, but when you're playing you're not just cranking out a full level continuous sine wave either, so the amp not working at the edge. Your cables should be fine too. I wouldn't sweat the power cord. Hopefully whoever manufactured the speakon cables used reasonable gauge wire, but at these short runs, it doesn't matter that much either. Bigger in both cases is better but probably won't fix the problem. What you do want to watch for is to make sure the preamp is not overdriving your poweramp. QSC has a sort of odd setup that should work fine but doesn't work the way it looks. Most of the QSC amps have a set of LED level/clip indicators and input gain knobs on the front panel, but the controls don't match the indicators! The LEDs are showing OUTPUT level clipping, so when that top LED flicks on, you're generating full output power. There's no visual indicator on these amps for when you're overdriving the power amp front end and QSC amps have slightly higher sensitivity than most (e.g. generate full power at slightly lower signal input level) too. I think the way that you can find the right settings for the input gain knobs on the QSC would be to set the volume level of your f1-x pretty high (maybe 3 o'clock), set the input gain on the power amp pretty low (maybe 9 o'clock), the play hard and slowly increase the power amp gain until it doesn't sound clean anymore. Obviously, this can be pretty loud, and you have to try to determine the difference between the speakers distorting from too much input power and the power amp distorting from too much input signal. But with an 8 ohm cab, and being somewhat gentle, you shouldn't be endangering the speaker too much. The input gain level where you start developing overload is the max you can run the power amp cleanly - more than that and the preamp output will overdrive the power amp. You won't get more volume, just more distortion. Because the sensitivity is high, you may find that the max input gain is at 12 o'clock or even lower. You're still developing the full power that this amp can make, even if it looks like it's only turned up half way. Now, when you want to adjust your stage volume level, do it with the preamp volume instead of the power amp input gain. Then you'll always have a clean signal. You can also turn the input gain down on the QSC, just don't turn it up past the max point you determined. Not having an input level clip indicator on the QSC seems like a bit of a boner. The traditional setup in the old days would be to turn the input gains to the max and control the volume with the preamp knob, but because of the sensitivity, it difficult to control the preamp volume without crossing into the distortion zone. It's easy to claim that QSC was playing specsmanship (if you set the amp up this way, it will be producing full power with the input gains at half for most signal sources and that makes the amp look more powerful than one where the input gains are cranked to generate the same level, but in the QSC case, that additional gain is not usable). That may be the case, but there's no real standards on these levels, so who's to say? When you turn up the bass knob on the preamp it will REALLY increase the power level that you're asking the amp for. Your ears perceive volume logarithmically which means that things that sound twice as loud take 10x the power. Crank the bass knob and you can go from asking for 100w from the amp to 1000w very easily. The watts thing is kind of kooky these days too; again, a game of specsmanship. The power supply in a QSC amp is a switching supply that operates a Class H amp. Unlike an old-school Class AB amp with transformer power supply, modern amps like the QSC can generate enormous transient power but can't dissapate the heat of driving these levels continuously. So, the really high power ratings are a bit of a fallacy. The power supply of an old Crown DC-300A is slightly less than 50% efficient, but within that design spec, the power supply and output transformers can crank out the 250-300watt for days at a time. The power supply of a QSC is probably 90% efficient and can make a real burst of 2400 watts, but if you tried to sustain that probably even for seconds the entire thing would melt down. Building a 2400 watt traditional amp would require 4800 watts of AC in which is more than your electric oven uses even when fed at 240v! Again, this isn't a fraud - although you probably come as close to a high level sine wave as anything out there, your continuous levels are much lower. I think you'll probably be able to realize a great increase in clarity when you get the input gain situation cleaned up. That may be enough to get you fixed up. If the clean output level isn't high enough, then I think you would want to try that second cab. Increasing the cabinets sucks from a hauling standpoint but is probably the only way to really fix the problem. David Fung | ||
| dfung60
Advanced Member Username: dfung60 Post Number: 333 Registered: 5-2002 |
You should have plenty of power at the power amp. 2400 watts at 2 ohms is roughly equal to 1200 watts at 4 ohms and 600 watts at 8 ohms. The power ratings are usually reflective of an "impending meltdown" level which doesn't reflect real stage conditions, but when you're playing you're not just cranking out a full level continuous sine wave either, so the amp not working at the edge. Your cables should be fine too. I wouldn't sweat the power cord. Hopefully whoever manufactured the speakon cables used reasonable gauge wire, but at these short runs, it doesn't matter that much either. Bigger in both cases is better but probably won't fix the problem. What you do want to watch for is to make sure the preamp is not overdriving your poweramp. QSC has a sort of odd setup that should work fine but doesn't work the way it looks. Most of the QSC amps have a set of LED level/clip indicators and input gain knobs on the front panel, but the controls don't match the indicators! The LEDs are showing OUTPUT level clipping, so when that top LED flicks on, you're generating full output power. There's no visual indicator on these amps for when you're overdriving the power amp front end and QSC amps have slightly higher sensitivity than most (e.g. generate full power at slightly lower signal input level) too. I think the way that you can find the right settings for the input gain knobs on the QSC would be to set the volume level of your f1-x pretty high (maybe 3 o'clock), set the input gain on the power amp pretty low (maybe 9 o'clock), the play hard and slowly increase the power amp gain until it doesn't sound clean anymore. Obviously, this can be pretty loud, and you have to try to determine the difference between the speakers distorting from too much input power and the power amp distorting from too much input signal. But with an 8 ohm cab, and being somewhat gentle, you shouldn't be endangering the speaker too much. The input gain level where you start developing overload is the max you can run the power amp cleanly - more than that and the preamp output will overdrive the power amp. You won't get more volume, just more distortion. Because the sensitivity is high, you may find that the max input gain is at 12 o'clock or even lower. You're still developing the full power that this amp can make, even if it looks like it's only turned up half way. Now, when you want to adjust your stage volume level, do it with the preamp volume instead of the power amp input gain. Then you'll always have a clean signal. You can also turn the input gain down on the QSC, just don't turn it up past the max point you determined. Not having an input level clip indicator on the QSC seems like a bit of a boner. The traditional setup in the old days would be to turn the input gains to the max and control the volume with the preamp knob, but because of the sensitivity, it difficult to control the preamp volume without crossing into the distortion zone. It's easy to claim that QSC was playing specsmanship (if you set the amp up this way, it will be producing full power with the input gains at half for most signal sources and that makes the amp look more powerful than one where the input gains are cranked to generate the same level, but in the QSC case, that additional gain is not usable). That may be the case, but there's no real standards on these levels, so who's to say? When you turn up the bass knob on the preamp it will REALLY increase the power level that you're asking the amp for. Your ears perceive volume logarithmically which means that things that sound twice as loud take 10x the power. Crank the bass knob and you can go from asking for 100w from the amp to 1000w very easily. The watts thing is kind of kooky these days too; again, a game of specsmanship. The power supply in a QSC amp is a switching supply that operates a Class H amp. Unlike an old-school Class AB amp with transformer power supply, modern amps like the QSC can generate enormous transient power but can't dissapate the heat of driving these levels continuously. So, the really high power ratings are a bit of a fallacy. The power supply of an old Crown DC-300A is slightly less than 50% efficient, but within that design spec, the power supply and output transformers can crank out the 250-300watt for days at a time. The power supply of a QSC is probably 90% efficient and can make a real burst of 2400 watts, but if you tried to sustain that probably even for seconds the entire thing would melt down. Building a 2400 watt traditional amp would require 4800 watts of AC in which is more than your electric oven uses even when fed at 240v! Again, this isn't a fraud - although you probably come as close to a high level sine wave as anything out there, your continuous levels are much lower. I think you'll probably be able to realize a great increase in clarity when you get the input gain situation cleaned up. That may be enough to get you fixed up. If the clean output level isn't high enough, then I think you would want to try that second cab. Increasing the cabinets sucks from a hauling standpoint but is probably the only way to really fix the problem. David Fung | ||
| kungfusheriff
Senior Member Username: kungfusheriff Post Number: 683 Registered: 8-2003 |
I used to use a Mesa 210 as a standalone in similar circumstances and had the exact same problem. My sound improved immensely when I went back to 15" speakers, specifically EVs in Bag End cabinets, which are great speakers in managably-sized boxes. Next gig, try standing the 210 on end -- vertically -- on top of the 15, and if that doesn't give you enough low-end projection borrow an 18 and use that. | ||
| eldiablo
Junior Username: eldiablo Post Number: 13 Registered: 3-2008 |
Jazzy I would definitely follow David's advice on input levels and Flip hit the nail on the head with adding the 15". | ||
| jazzyvee
Senior Member Username: jazzyvee Post Number: 1179 Registered: 6-2002 |
ok next gig I will try to get to the venue early and try some of your suggestions. Thanks for the advice. Jazzyve | ||
| jacko
Senior Member Username: jacko Post Number: 1779 Registered: 10-2002 |
Jazzy. A point to consider - there's a clip limiter switch and a Low frequency switch on the back of the QSC for both channels - how do you have yours set? Graeme | ||
| keurosix
Advanced Member Username: keurosix Post Number: 307 Registered: 10-2005 |
Jazzy, One point that has been glanced over: The ultra low bass frequencies below the fundamental of your bass suck up tremendous power, and can cause all manner of gremlins to show their ugly faces. If you are using a 4 string, (low E ~ 40 Hz) or a 5 string (low B ~ 32 Hz) you don't want your system to try to reproduce any frequencies below the lowest fundamental. You can prevent this by applying a high-pass filter at the lowest fundamental with a steep curve so that it rejects lower frequencies. The result will be cleaner sound all around: The amp and the speakers will be happier, and so will your ears. In fact, you should perceive more bass output at the desired frequencies with this approach. Depending on your preamp or crossover or SF-2 you should be able to dial in a low frequency high pass and maximise your low end punch. The SF-2 in a low pass mode at a low frequency center can really generate a huge power hungry monster that will do more harm than good. Try a little experimenting with this. Kris | ||
| ivartshiva
Junior Username: ivartshiva Post Number: 26 Registered: 10-2007 |
Friends, there's a lot of technical stuff in this thread that I know nothing about - however I have a little experience with the 'hillbilly' setup of no sound reinforcement other than a vocal PA - in fact, anything else, for me, is fabulous luxury! Also I have more experience in this old school style setup as a guitar player, but the same thing seems to be true for bass: as Mr. Fung mentioned above, "EQ your stage amp such that it sounds good out in the crowd, even if you're way too loud and bassy on stage." As far as I know, this is the only way to go in this situation. I'm playing reggae using a wireless and playing 4-string through an SVT-3PRO (450W) and an Ampeg 4x10 SVT410HLF, made for enhanced low end, and it sounds great in medium-sized room, and even outside within 100 feet, but 1) next to the amp, when the sound is right out front, it sounds like a freakin thunderstorm, way too loud and bassy for a pleasant 'stage mix' experience; and 2) I'm not talking about getting a super-lowend hip-hop modern ultrabassy stomach-flopping ear-assaulting, sickening 21st Century bass sound, but a truly musical, sweet, rich, punchy, full powerful authoritative bass sound. I heard Toots and the Maytals recently and the soundman had no clue how reggae bass should sound - it was a way-low end washout mud until someone from Toots' crew came and cut out that super low-end shite (can I say shite?) and suddenly it was music instead of sound effects. The sound man changed it back a couple times and the same guy would come back and fix it. I think the moral is: just because your house sound system can break rocks and melt lead pushing gross low frequencies, only adolescent teenagers in low riders wanting to shake and annoy urban areas really want to hear that. Or maybe I'm an old guy and not with it Michael |
