Problem with my SVT4PRO???

[slash]

oi!

i'm hoping someone can help me with a weird situation i seem to be in... any suggestions or reccomendations are greatly appreciated!!

so i just got a brand new Ampeg SVT-810E/AV cabinet, out of the box! and i plugged in my SVT4PRO head to play it.
(Now before i get into the issue, i have been renting the EXACT same cabinet from the music store since December while i've been waiting for this brand new cabinet which was on back order and i had JUST finished recording my bass tracks for my band's album a couple weeks ago and the head and cabinet were running PERFECT and it sounded EXACTLY as i wanted it to...)
SO! i plugged in my SVT4PRO exactly as i always do and plugged in my bass (Modulus Quantum 5). However, when i started playing i noticed that on every single note it was peaking! especially on the A, E and B strings. It also sounded like there was a slight distortion in the sound. As if there was a weak distortion pedal running in my signal. (Even though i have the compression knob turned up)

Usually when this happens it means the two 9volt batteries in my Modulus are dead... even though these batteries are practically new, i changed them to be sure... nothing changed. I then tried my old Peavey Foundation on it to try and gather an idea of what's going on... crystal clear! so i switched back to the Modulus and it still sounded distorted.

I have just tried my Modulus on my Fender Bassman 250 and it sounds PERFECT! so i am lead to believe that there must be something going on with my SVT4PRO! (or god forbid! my brand new 810 cab!!!) but why would it react this way to only ONE of my basses all of a sudden? also the fact that it is the ONLY one that gets played through this head on a frequent basis.


if someone or anyone has ANY idea what it could be! i would GREATLY appreciate any advice here, this is a little upsetting!!

thanks!!

 

[anderbass]

That's really weird slash.

Unless you discover something else, I think I'd be hauling that amp and Modulus down to the store to see if that older rental does the same thing.
It probably wouldn't matter, but are your using a brand new Speakton cable that might possibly be wired incorrectly?

 

[slash]

not a brand new one... but the same one i've been using the past little while!

i AM tempted to do what you're saying though...

 

[JimmyM]

I have had that exact problem with my SVT 3 Pro. I dug it out recently and took it to the local guy for SS amps around here, and he said all it needs is a cleaning and an adjustment and is charging $40. He said as the components age, their values drift and it needs to be adjusted to compensate. Sounds a lot like biasing in tube amps, but I wasn't aware you needed to do something like that in hybrids, too.

I have no idea if that's the answer, but I'll know in a couple weeks.

 

[ErnieD]

I bought a floor model GB212T cab at a local music store, so I know it had been played thru while it sat there, hell I played thru it a few times before I bought it. So a few weeks later I order the same cab new from AMS online store. The cab arrives, new in the box. I take it to a gig that nite at the same club, same amp GB750 and same bass that Ive used with the floor model cab. The newer cab just seemed to break up more readily and did not sound as crisp, tight as the older cab. I posted here asking if cab/speaker break in periods are trully needed with new cabs. Consensus was, NO, not really. Maybe the different cabs, tho from same maker, just have tonal differnces that happens at the manufacture level. Ive been using both cabs together lately so I dont notice the difference anymore, still???

 

[Warpeg]

Check out the preamp section of your 4-pro. If you're Modulus puts out a hotter signal than your Peavey, and your preamp gain is set pretty hot, then you might be getting distortion from there.

 

[Son of Bovril]

maybe back off on the compression as that can add slight distortion too