SVT4/dual channel compressor configuration

prion86 · #1 05-10-2010, 01:55 PM

If this should be in Live sound, I do apologize.

First, a little background:

I have an SVT4 that I run mono-bridged into my 610HLF. I am somewhat of a noob when it comes to the back side of the amp; it has always been mono-bridged out via Speakon to the cab. I have a BBE Maxcom arriving shortly, which I had planned on just running through the FX loop, but then I got to thinking:

'This amp has a crossover...I wonder if there is a way to send the highs to one compressor channel and the lows to the other (more or less bi-amped), set the compression/maximizer settings for each frequency range, and still run it mono-bridged to the single cab'?

There are a good many threads here on bi-amping with multiple cabs, but nothing about splitting things out, and then combining them at the power amp stage. I realize this may not add anything to my sound, and may actually make things worse, but I want to make sure I don't blow something up tinkering with things. Some questions I had:

-What is the signal that is coming from the bi-amp outs? From what I can make of things, those are line level (adjustable via front knob) and post crossover.

-If I can run those outputs into the compressor, I assume I can run them back into the power amp inputs. If I do, will leaving the amp in mono-bridge still combine the signal to the single speaker output, or does the bridging happen before those inputs?

-Does anyone have a similar rig (SVT4 PRO/dual channel compressor) configured in such a way? If so, is it even worth the trouble?

-Is this all clearly documented somewhere that I failed to notice? A nudge in the right direction would be much appreciated.

-Am I completely out of my gourd with this line of thinking?

It isn't going to ruin my day if I can't patch together such a configuration. I just thought it would allow for grater control, and if nothing else, interesting tonal possibilities.

Thanks in advance.

DanRJBrasil · #2 05-10-2010, 03:15 PM

just patch the biamp signal through the comps to the power amp input a and b , and run it as mono try it out and let us know how it work out for you

bongomania · #3 05-10-2010, 03:57 PM

Yes, it should work fine. Treat the power amp channels as separate inputs, but mono-bridge the power amp output.

While I don't have an article explicitly describing your situation, you might get some value out of my articles on preamps, line-level, and dual-band compression (in the FAQ in my sig).

prion86 · #4 05-10-2010, 04:23 PM

Thanks for the input.

Dan - I was thinking that would be the way one would patch it.

Bongo - I admit I have not looked over everything yet, but I have spent quite some time going through your contributions on the subject of compression. I thank you for the work you have put in; it has been quite informative, and will no doubt continue to be so.

I was hoping to have the Maxcom racked and fiddled around with by now, however the UPS fellow and I keep different schedules. Hopefully, I'll have an opportunity tomorrow (it's probably for the best...I'd have otherwise been forced to split my attention between my toys and the Pens game tonight).

Another question for those more experienced than I:

Would it be better to use .25 in -> XLR, or just use .25 in shielded patch cables?

Again, thanks in advance.

bongomania · #5 05-10-2010, 04:36 PM

Check the manual of the SVT4. I am guessing its send and return jacks are unbalanced only, in which case there would be no benefit to using XLR's at the Maxcom end.

Kraken · #6 05-11-2010, 06:40 AM

How does the 610HLF handle the SVT 4 Pro when Mono Bridged? this is the same rig I have, but I asked Loud and they advised against doing it (they did say unofficially you can, but obviously the risk of blowing a speaker is that of the owners to take)

I figured as I didn't know the rig very well (still don't really but I'm getting there) I didn't want to push it.
any advice on this would be appreciated.

BTW I think Bongomania has steered you in the right direction for this compressor.

something else for you to consider would be to look at the Lows/Full Range biamp option in the SVT4 Pro manual and get yourself a 15"/18" speaker cab to run the lows.

run like that the SVT 4 Pro can go down to 2 Ohms on each channel (I believe), mono bridged can only handle 4 Ohms.

Peace.

prion86 · #7 05-11-2010, 08:32 AM

Kraken -

The 610HLF handles the SVT4 just fine. Granted, I am not playing in situations where I have to turn it up all the way, so I am unsure of what would happen under those circumstances. I suppose the SVT4 could technically fart out just about any cab one hooked it up to under the right circumstances, but I have not had any problems. I also have never had the occasion to turn it up to 11, so YMMV.

In the group I play with, guitar x2, vox x5, and kick drum all go through the PA. I am on my own, so I am competing with all of that running through two QSC 1400 watt amps (I prefer it this way...more control). Running one channel in the SVT was enough to cut through, but I had the thing turned up about ~60%. When I mono-bridged it, I found I could back down to ~40% and leave my instrument level at about the same and get a similar volume level. I feel like I have a lot more headroom if I were to need it. Also, with my levels set a little lower, it doesn't ever sound the least bit muddy or overdriven. Granted, the rooms we play are not all that big, and if they are, they often just DI me into the house anyway.

All in all, I am quite happy with the sound I am getting. I mostly run my Thumb BO through it via an X2, but my Tobias and my Ibanez sound just as good. Each instrument really has it's own personality, but I have the EQ set up so I don't have to fool around with it too much if I need to swap one of them out. I have been using this setup going on four years now, and I still feel like I don't really know it as well as I'd like, so I know what you mean.

One bit of advice though - It has been repeated countless times on TB, but make sure the SVT has adequate ventilation. I had it shut down on me once because it overheated. Luckily, it was the last song in the set, so it wasn't a huge deal, but it still happened. Once in four years isn't bad though. I stuck a little clip-on fan in the back of the rack to keep the air circulating, and have not had an issue since (it actually runs a little cooler now).

For the most part though, I am happy with the rig as a whole, my band mates are happy with it, and the "civilians" that come to see us don't complain either. I do occasionally send out some harsh crunchy sounds on the high end (I know...technique) so I am hoping I can reign some of that in with the compressor. Running the bi-amped outputs through each channel on the comp should handle that, while allowing me to get a little more low end sustain. I was also thinking this would effectively give me a four band sonic maximizer (low and high for the low side of the crossover, and the same for the high end). I had not really seen any documentation on a setup exactly like this, so I am interested in seeing if there is any benefit. I have a show on Saturday, so I'll definitely be back to report my first impressions on how this behaves in the wild.

As far as getting my hands on a cab with a bigger driver, I would be fine running a true bi-amped setup if I A) had the cash in my pocket to snag such a cab, and B) wanted to try to shoehorn something else into my vehicle.

Cheers