concerns with volume jump fx & sub harmonics?

[bovine mind]

Curious if any can help cure my paranoia over preamp/power amp clipping and damage to speakers using fuzz/overdrives that boost volume and synthy sub bass type fx.

My setup:

Stingray 4 > korg pitch black tuner > ISP decimator > EHX bass micro synth > boss ps-5 > boss ps-3 > 80's rat > PE depth charge > EHX small stone > akai headrush > fender BXR 400 amp biamped hi/low outputs @ 200 watts 4ohms each > ampeg 1540 HE 4x10 / 1x15 cab [ hi/low inputs @ 200 watts & 4ohms each ] > surge protector.

I can't find the manual to the fender head [anyone have a copy?] that explains exactly what is going on when the two clip LED's light up, listed A and B. i assume A is for the preamp and B is for the power amp. Both flicker about 75% of the time with the built in amp compression turned on. the crossover is set to send all freqs under 800hz to the 15 and anything above to the 4x10. there is a hi/low balance knob, but i'm not sure what it does, i have it set midway at 12:00.

eq on my bass is volume 2/3 way up, bass knob slightly boosted, mids flat, high slightly boosted.

my eq has the first three lower eq sliders boosted in a moderate curve and the last few higher eq sliders boosted. i've read about eqing on my bass first and flat on the amp and cutting instead of boosting but i can't seem to get the huge bottom and punch i need without my current settings. there is a link to my band's myspace below to hear the sound i'm looking for, heavy psych/sludge/noise oriented.

the depth charge has a huge jump in volume when in engaged at these settings: volume 6, with blend, tone, and gain cranked. the rat has the volume knob almost cranked. i love how they both tear through my band mix and don't want to turn the volume knobs down but am concerned about my speakers. i've got the sub octave cranked on my EHX bass synth as i can't live without the insane subs. i don't hear too much woofing/farting/bottoming out sounds.

i just replaced my hartke 5000 amp as it had a loud popping sound issue and would turn off spontaneously. i'm wondering if i damaged it due to this kind of approach. i also had my cab repaired - the subwoofer in the 15 had "malfunctioned" as did some component in the biamp section of the back of the cab, but the tech said they were manufacturing flaws and did not happen as result of my settings.

how concerned should i be about blowing speakers or damaging my amp and cab? should i look into getting a separate cheap limiter like the guyatone bl-2 or is the compressor in my head doing the job hence the clip LED's? lastly, should i plug into a wall socket or surge protector? i can't quite go off without worrying at the moment, but don't want to sacrifice the massive, punishing effects i'm using.

www.myspace.com/lateyoung
for reference
thanks

[bongomania]

You absolutely should be worried about blowing speakers. In order to get a very low frequency to be "loud" and project well, it requires a lot of power, even with a very efficient speaker. A speaker cab's power handling rating is not a real depiction of what it can handle under all circumstances- for example the impedance and power handling will vary with the frequency of your signal. It is highly likely that your speakers are not really able to handle their rated wattage in those sub-bass frequencies, and will fart out, possibly tear, and even possibly overheat and burn/melt if those frequencies are sustained at full power for extended periods.

That said, if you are not hearing any distortion then you are probably not causing any problems. Listen for that farting sound and then back off.

And that said, I do strongly recommend a limiter. A good limiter will allow you to get the most "loudness" and fullness out of your intense effects, without exceeding the peak limit you set. The compressor in your amp head is trying to do the job, but I 100% guarantee it is not really up to the task.

Also I'd get more speakers- that way you can get the same loudness, but spread the stress around among more speaker surface area, reducing risk of damage.

[bovine mind]

Thanks Bongo. i have read your replies on similar subjects long before deciding to post here. i'm almost out of board space and $, so the BL-2 looks the best option right now for cost and size. your comments on your page seem to sell it for what i'm doing. will the limiter cut the huge jump in "loudness" i hear when i engage the depth charge? what exactly with it "limit" in terms of hearing and amp damage?

i've thought about upgrading to an 8x10 as i do want more speakers/watts but don't want two lug two cabs, but may have to invest in a good subwoofer. not sure how i would biamp the cab and add a subwoofer with the same amp. we like to venture into extended heavy drone and pushing sub eq for an hour worries me. my interest in reproducing live the huge sub bass found in electronic music is digging me into a money trap.

it strikes me as strange that ampeg would manufacture a cab just as huge and heavy as an 8x10 but with half the watts trade for biamp options when you inevitably will want more speakers. perhaps that is why it was discontinued.

[bongomania]

The BL2 limits and it also has an output level knob, so it can be used to reduce the signal level as much as you want. However it can only do its job if you are careful and thoughtful in how you set input and output levels throughout the chain. For example if you set it to limit the big bassy peaks and then you kick on another pedal which increases the signal level going into the limiter, then the signal will be squashed and not have much dynamics left. That can work out OK, it depends on whether you like the sound in that context. Another thing to consider is that sometimes compression can take the edge off of distortions, sometimes even canceling the distortion effect almost completely (not technically accurate, but for practical purposes). But not always, so you'll have to experiment to find out. The Depth Charge has a volume knob- is it not working for you?

[cheapbasslovin]

Seems to me that bi-amping may not be your biggest friend here. If you are biamping with a 50 /50 split, then you are having one 200W amp do all the heavy lifting while the other gets off easy. If your 200W isn't all that efficient, then you probably don't have that much headroom. I would suggest trying 400W full range once and see what kind of sound/performance you get out of it and see if it cleans up your amps clipping.

Sounds to me like you are playing loud enough that you may need more headroom in both your amp and cab.

IMHO blah, blah, blah.

[JohnDavisNYC]

the cabinet is probably fine, but i would go for around 1000 watts of solid state power for that kind of stuff, and probably NOT bi-amp. I really like those cabinets running full range. I generally find that an Ampeg SVT4pro has more than enough headroom for sub bass stuff at high volumes, but that is just my experience with that as my backline request on tour, you could probably get even more specialized with a seperate pre/poweramp setup.... or buy a WalterWoods... that is my main amp, and it has amazing headroom and great tone. I think it is like 450 watts, but much 'better' 450 watts than a lot of other SS amps...

john

[bovine mind]

Originally Posted by cheapbasslovin

Seems to me that bi-amping may not be your biggest friend here. If you are biamping with a 50 /50 split, then you are having one 200W amp do all the heavy lifting while the other gets off easy. If your 200W isn't all that efficient, then you probably don't have that much headroom. I would suggest trying 400W full range once and see what kind of sound/performance you get out of it and see if it cleans up your amps clipping.

Sounds to me like you are playing loud enough that you may need more headroom in both your amp and cab.

IMHO blah, blah, blah.

The head's "balance" knob i assume is to help spread the wattage to each cab. as my lows are eating most of my power i assume it would be best to crank this more towards the lower end, and hopefully feed the 15 more power, though i haven't found any explanation as to what this knob actually does. maybe more of a 300-low 100-mid/hi split.

[bovine mind]

Originally Posted by JohnDavisNYC

the cabinet is probably fine, but i would go for around 1000 watts of solid state power for that kind of stuff, and probably NOT bi-amp. I really like those cabinets running full range. I generally find that an Ampeg SVT4pro has more than enough headroom for sub bass stuff at high volumes, but that is just my experience with that as my backline request on tour, you could probably get even more specialized with a seperate pre/poweramp setup.... or buy a WalterWoods... that is my main amp, and it has amazing headroom and great tone. I think it is like 450 watts, but much 'better' 450 watts than a lot of other SS amps...

john

The SVT 4 pro looks great @ 600 watts, i assume it would be safe to run that amount at a higher rating than what the cab is [400watts], getting louder before clipping, so long as i don't crank it? i doubt i could afford it anytime soon. What would be the benefit of having a cab this huge and heavy only to use it in 400 watt full range mode? it seems the only benefit it has over spending around the same price and buying an 8x10 for added speakers and headroom @ 800 watts @ the same size and weight is it's bi amp option to send lows to the 15", which i assumed would handle the problems i'm having as one speaker would be more dedicated for the lower end. i have a couple options for trading to an 8x10 right now but am hesitant to give up this rare cab.

unfortunately the fender BXR 400 head i have cannot be bridged, only can run each 200 watt channel stereo or bi amped, so i don't think i'll get 400 watts into the full range input on my cab. hopefully i'm wrong.

[bovine mind]

i've also thought about using the DBX sub harmonic synth at some point as it has some neat limiting options and would be nice to have as a rack and free up pedalboard space. i can't tell how it's engaged though. is there an option for a footswitch or can it only be left on constantly?

[bongomania]

I had one of those, and the only bypass is a pushbutton on the front panel. It does not have any limiting options.

[bovine mind]

Originally Posted by bongomania

I had one of those, and the only bypass is a pushbutton on the front panel. It does not have any limiting options.

i could probably deal with a pushbutton. why did you get rid of it, & how/what context did you use it?

[bongomania]

I was using it for bass and bass-heavy electronic noisemusic, in conjunction with a couple of Mackie powered subwoofers. I got rid of it because I got more effectively deep sounds by emphasizing the fundamental of my signal rather than adding additional lower-frequency content. If I was to get one again it would be for early-Pino-style playing the high notes through an octave-down effect.

[cheapbasslovin]

Originally Posted by bovine mind

The head's "balance" knob i assume is to help spread the wattage to each cab. as my lows are eating most of my power i assume it would be best to crank this more towards the lower end, and hopefully feed the 15 more power, though i haven't found any explanation as to what this knob actually does. maybe more of a 300-low 100-mid/hi split.

I suspect that it does balance the high/low ratio, but I'm skeptical of it being able to deliver more than 200W per side. I know that my bi-amped rig is only capable of 300W per side or 600W bridged, I can't force 500W onto one and 100W to the other.

If both sides of your Ampeg are capable of separate full range function, then I would try running your rig in stereo rather than crossover and see if you can ease the overall draw on your amp. But that is just me.

I don't claim to know that your amp is only capable of 200W per side, I can only surmise from what I know of other bi-amp setups. I hope you get it all hashed out.

[bovine mind]

Originally Posted by cheapbasslovin

I suspect that it does balance the high/low ratio, but I'm skeptical of it being able to deliver more than 200W per side. I know that my bi-amped rig is only capable of 300W per side or 600W bridged, I can't force 500W onto one and 100W to the other.

If both sides of your Ampeg are capable of separate full range function, then I would try running your rig in stereo rather than crossover and see if you can ease the overall draw on your amp. But that is just me.

I don't claim to know that your amp is only capable of 200W per side, I can only surmise from what I know of other bi-amp setups. I hope you get it all hashed out.

thanks, i depressed the Biamp mode to Stereo on the fender head and plugged both hi and low outs into the hi and low ins on the cab. it now sounds much more full and, well, louder. why is that? both clip LEDs are still flashing though. can i assume it's OK to push my head this hard if the LED's are flashing but i'm not hearing any nasty distortion or farting?

[cheapbasslovin]

IME:
Flashing = careful

Holding = stop.

Flashing usually means that you are approaching the limits of the amp, but if the LED's linger on, then you are pushing your amp too hard. Amp manufacturers usually set the clip LED function so that it lights up a little below the danger zone so you can see that you are approaching the limits. This way if it flashes a little you are good, but if it holds you know that you are living in a dangerous place.

It's louder because your 15 and your 10's are all getting the full sonic range. Before you were sending all your lows to the 15 and none to your 10s, but now the sound is evenly spread around to all your speakers. Instead of π15² worth of subwoofer surface area, now you have π55² worth of subwoofer surface area with which to spit monstrous sound. Biamping is super, but you need to have ample headroom (especially in the subwoofer section) to pull it off.

Just be careful when using new effect that you look to determine that it is not pushing your amp too hard. (Just thought I'd add that in lest this get moved to the amps forum, which I never go to because the GAS there is too expensive.)

[bovine mind]

thanks for all responses. i ended buying an SWR 400S bass amp head and have been using the built in limiter which seems to do a much better job than my fender bxr 400 head. I also added the guyatone bl2 bottom limiter to the very end of my pedal fx chain to tame the volume spikes from my depth charge fuzz, phaser, and delay. i leave it off when i have my depth charge on as it sadly almost totally neuters the intense fuzz, i guess characteristic to the nature of compression/limiting. however i removed the guyatone to see if was really needed and doing what it says, especially as my built in limiter seems to perform well. without the guyatone in my chain the pre amp clip LED flashed 90% of the time with my delay, phaser and fuzz all on. i added it again but left it OFF and noticed the LED is no longer flashing. how is it possible the guyatone is still keeping my preamp from clipping when it's OFF?

[bongomania]

Good question; my first guess is that it's because the Guyatone is not true bypass, so there is some loading of the signal even though the limiter is switched off, and maybe that loading is enough to suck some of the intensity of whichever resonant frequency was causing the meter to flash.