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gain control question for head and power amp.

Discussion in 'Amps and Cabs [BG]' started by Mr. Pitiful, Jan 25, 2003.


  1. Mr. Pitiful

    Mr. Pitiful

    Jan 22, 2003
    Fargo ND
    I play with a LOUD guitar player on stage, and as a result, my SWR 350 would clip trying to keep up. So, I bought a QSC 850 watt power amp, since all my cabs are rated around that at 4 ohms anyway. I am getting a much cleaner sound now,BUT am not getting the stage volume gains without the clipping.It is the power amp that is clipping now, not the SWR, which is too high, the volume on the head or the amp? I am using my SWR 350 as a pre amp only now, and my QSC is bridged so I am only using the left channel. How do I set my volumes on the SWR and the QSC for best control, I am at about 7 and 7 now. Should I have my SWR head cranked and not the QSC? just the opposite? a mixture? I just dont want to have alot of clipping and blow my speakers with that much power. If it helps, since I started running the power amp, all my SWR controls are set dead center flat, And I run clean, no effects. Thank you.

    Mr. Pitiful:confused:
     
  2. Petebass

    Petebass

    Dec 22, 2002
    QLD Australia
    850 watts and not loud enough? That's farken a loud band you've got there.

    Clipping is usually the result of a hot input signal. I'd turn the QSC amps up full belt and turn the input gain on the preamp down. You should get all the volume without the clipping.

    When you've done that, smack the guitarist over the head with a 4x2 plank of wood until he turns down. If that doesn't work, conduct all your conversations with him at yelling volume. If he askse why you're yelling, swear black and blue that it makes you sound better...... he'll get the picture (eventually).
     
  3. Mr. Pitiful

    Mr. Pitiful

    Jan 22, 2003
    Fargo ND
    its to the point where our guitar player of about 14 years with the band, is so loud, that we cant control him on the board. I wear in ear moniters and have him completely off in my mix, and hes STILL louder than me in my moniters from what the my vocal mike pics up. I can hear my bass fine through my moniter, but the stage volume just isnt there, I wonder if I am running this all correctly. My SWR doesnt have a amp jack, so the salesman at Guitar Center told me to use the send as my signal to the amp, and that effectively will do the same thing and also shut off the power from my SWR head. I tried cranking the QSC at last nights gig, and had the SWR at bout half, and it was still distorting occasionally. I know its not the cab, the cab is great, cant be the power amp, its brand new, I just dont know what I might be doing wrong with the SWR. I am sure that some of the problem is that I was running a Bag End 2x12 cab,(which is awesome) and the stage is small enough that I cant get away from my cab which is pointing at my ankles, and if I tilt it up I lose all the bottom. I have bigger cabinets I could use, but This one has been great at loud practices. Oh well, I have a new Eden 410XLT on the way that will sit a little higher, but still its frustrating.

    Mr. Pitiful
     
  4. Mr. Pitiful

    Mr. Pitiful

    Jan 22, 2003
    Fargo ND
    I forgot to mention, what makes it hard to believe is that I dont play in a loud metal band, its a variety soul, R&B, sixties rock, some classic rock, but mostly stuff like Chris Issack, Tommy James and the Shondells, Delbert Mclinton type stuff, and that our guitar player (whose gonna have to go) is 49-50 years old, and NOT hard of hearing. You expect this stuff when your 19, but not at his age.

    I love this forum, Its great to get real musicians honest opinions and suggestions.

    Mr. Pitiful
     
  5. Razor

    Razor

    Sep 22, 2002
    Dallas
    I gotta agree with Pete...it's probably clipping because the input signal is too hot. Turn the QSC up and use the QSC volume controls. The SWR shouls pretty much be used only for EQ'ing purposes and the gain and volume controls on the SWR should be at around 9 o'clock.
    You said you're using in-ear monitors....I used to use them but it really messed up my perspective on tone for some reason. (It's one of them stupid personal things). Since you're using those if I were you I would make sure you are loud/clean enough to the house sound or through the board and just up the bass a bit in your in-ear monitor because correct me if I'm wrong...you are really just using the rig on stage to feel your tone, and as a secondary monitor which kinda nulls itself out with the in-ear monitors.
    Grab you a good used SWR IOD preamp (or whatever you like) to use with that QSC and use the SWR head you have for practice at home or something.
     
  6. Mr. Pitiful

    Mr. Pitiful

    Jan 22, 2003
    Fargo ND
    Thanks for the help guys. By 9 o clock do you mean, say..3 or so on my volume? if 1 is at7 oclock and 10 is at 5 oclock? I usually wear only one ear monitor in at a time, mainly for my vocal, but also to help out with the bass, I go back and forth between one or both in at a time, usually just one though. I want to be loud enough that the drummer can hear what I am playing, we go through ALOT of drummers (its hard to find drummers that can play the Variety we play with equal feel for each style) so I want them to be able to pick up on what I am playing, and also to fill in the dead spot on the dance floor between the two P.A speakers.

    I think I will get me a new pre amp. Does that sound right as far as using the "send" for my pre amp out or is that too strong of a signal? also, should I use a better cable to run from my SWR to my power amp, or will a guitar cable or patch cord be sufficient?

    Thank you for all the help.

    Mr. Pitiful
     
  7. Razor

    Razor

    Sep 22, 2002
    Dallas
    Yeah 9 O'Clock is 3...12 O'Clock is 5 or 6....you get the picture.:D
    One of the drummers I am with now plys really hard and even has trouble hearing the mix through a 15" monitor right next to him. I daisy chained a 4x10 right behind where he sits so now he can really feel the thump. If you have multiple cab's you might try that.
    Until you grab yourself a preamp the way you are doing it will be fine. You are basically slaving off the SWR into the QSC. You want to connect your cab's to the QSC and use the QSC's volume/gain controls. EQ your SWR until you get the tone you want but just make sure you don't overdrive or distort the signal going into the QSC by having the gain and volume on the SWR too high. If you have an additional cab you could hook it into the back of the SWR for your drummer to have next to him. Just a thought. Good luck my friend. Now you have the perilous task of preamp shopping.
     
  8. Razor

    Razor

    Sep 22, 2002
    Dallas
    One more thing....if your SWR head has an XLR DI on it...and the QSC has an XLR input then I'd try using that first. Probably get less noise/hiss. If not then an instrument cable will work...if there's a lot of hum/hiss there then you might try a TRS cable but the first one should be fine.
     
  9. Mr. Pitiful

    Mr. Pitiful

    Jan 22, 2003
    Fargo ND
    Thank you all. I appreciate all the help.

    Mr. Pitiful