Post gain on my new 6505+ stopped working

[Maggai]

Just a few days ago I got a Peavey 6505+, been great. But when I got home now, and was gonna play, the post gain knob on the lead channel does nothing. The sound is as low as if it's on 0. It gets a tad treblier if I turn it up past like 6. Pre gain works. It worked perfeclty earlier today.

Anybody experienced this? How did this happen??? It's brand new. Fuck.

 

[JJO]

Well that's easy right? Send it back and let them check it up and be damn mad if they aren't gonna give you a replacement, since you need it fast n stuff right

 

[Maggai]

Yeah. Was kinda hoping there was an obvious solution that I had overlooked. Rythm channel works though. Goddamnit.

 

[J.DavisNJ]

Well that's easy right? Send it back and let them check it up and be damn mad if they aren't gonna give you a replacement, since you need it fast n stuff right

Sorry to hijack, but I dig your band "Blackest Grey." Are the myspace songs a 5150?

To the original poster: It's possible it could be a power tube or tubes. If you have some extra, try swapping them around.

-Joe

 

[GuitarHack]

Yeah. Was kinda hoping there was an obvious solution that I had overlooked. Rythm channel works though. Goddamnit.

Since the Rhythm Channel works then it shouldn't be a PowerTube problem. The 6505+ uses different combination of Preamp tubes when you are on the Lead or Rhythm channels. The tubes used in each channel are below:

5150II/6505+ Signal Path
Clean and Crunch
V1 (one half)
V6
V3
V4
Power Tubes


Lead
V1
V2
V5
V3
V4
Power Tubes

On the Lead, Preamp tubes 2 and 5 are used whereas they are not used on the other channels. Maybe one of these (or both) are duds, so you are not getting a preamp signal to amplify through the Poweramp section. The reason it get's a tad "treblier" is that you are maybe just amplifying the noise on the channel.

Tube order looking from the back Right to Left is this (written on the board also, so check that):

Power Tubes <------ V4 V3 V5 V2 V1 V6 Input Jack (V6 on Right side, V4 on Left side closest to Power Tubes)

Maybe try replacing V2 and V5.

Disclaimer: I think that this is correct, please don't hold me responsible for any damage .

That, maybe, or a failed Lead Post Pot, maybe.

 

[VH100R]

I'm pretty sure its a preamp tube gone bad...

 

[viggen666]

Yup, had that the same problem a few times back, it always was a bad preamp tube.

 

[Maggai]

Ok, thanks guys. Don't have any spare tubes around now, but I'll check it out tomorrow.

 

[Meisterjäger]

I wouldn't even bother swapping faulty tubes on a brand new amp, jus take that thing in to get fixed properly.

 

[J.DavisNJ]

Oh woops, I missed that part about the rhythm channel.

Listen to GuitarHack, he knows his stuff.

-Joe

 

[Maggai]

I just got the amp back, and it was indeed a bad preamp tube. Well now it works again. But this thing is so damn loud, I can't really play it here in the apartment without getting the neighbours crazy. Need to find a rehearsal place to have it where I can blast it and truly enjoy it. At low volume it doesn't sound very good.

 

[yarrick19]

I just got the amp back, and it was indeed a bad preamp tube. Well now it works again. But this thing is so damn loud, I can't really play it here in the apartment without getting the neighbours crazy. Need to find a rehearsal place to have it where I can blast it and truly enjoy it. At low volume it doesn't sound very good.

Check out the THD Hotplate!

 

[Maggai]

Check out the THD Hotplate!

Wow, that thing looks like exactly what I need! Thanks for the heads up!