Peavey 5150 II/6065+/6534+ EQ levels

[Dave Sloven]

Seems like that video was the last time my amp worked properly.  I suspect V3 needs to be replaced, as when I have the effects loop engaged the amp is very quiet, like when I had a noisegate with a flat battery in the loop.  I thought it might be a cable or a pedal but I plugged it all in to my Classic 30 and the effects loop was fine there.

I'm estimating roughly 200 hours playing time since buying the amp ... if it normal for tubes to wear out that fast?  I'm hoping it's not something else

[Mutant Racer]

Preamp tubes are supposed to last a long time but it is common to get a bad one. A lot of players usually keep a spare laying around it happens often enough. A solid preamp tube can last decades.

[Dmoney]

In a normal 5150 and the 5150II and associated 6505 amps the valve which makes up the loop send and return stages is always engaged. When you bypass the 'loop' all that happens is the send and return jacks are bypassed, not the whole loop. Therefore I would suggest the issue is not the valve as when you have no effects in the loop the signal still passes through that valve in the same way.

Unless you get a schematic for you amp or reverse engineer the loop to prove otherwise, I reckon it's either the jacks or something in the loop that is causing the problem.

[Dave Sloven]

Oh, okay, thanks, it's probably the jacks then as the whole board works fine with my other Peavey (Classic 30).  I'll try the old contact cleaner trick and see if that fixes it.

[Dave Sloven]

It was dirty jacks, presumably either the send or return jack (or both).  CRC Contact Cleaner sorted it out

[CommonCourtesy]

I hope my 6505+ surpasses 200 hours of playing without having to change any tubes!

I don't expect to be using it much for a few months anyway as the band is in writing mode and I use the rehearsal room amps.

Should set a day though where we all set up our live rigs and try to get a good sound together. Something we don't get to do much.

[Dave Sloven]

It wasn't the tubes, it was just dirty loop jacks on the amp.  It will happen eventually.

Just spray contact cleaner on the end of your cable, push it in and out of the jack a few times, and wipe with a paper towel.  If that doesn't fix it then look at tubes

[CommonCourtesy]

Ah I must've missed that. I have Servisol which I use whenever I get crackly pots or input jacks, usually does the trick.

[Dave Sloven]

It wasn't crackly, it just had a huge volume drop through the loop.  Reminded me of when my battery started to go flat in the ISP before I got the T-Rex power supply.

If you ever experience this just clean it as I said above.

[Dave Sloven]

The loop is playing up again.  Surely it can't be dirty again only a couple of days later?  Again the issue is volume drop

[SirJackdeFuzz]

if you don't like how your amp is EQ'd you can always change it.

the number on the dials don't really mean much. It's just a marker so you can remember where the knob points more easily for a sound you like. using  6 6 6 across bass middle and trebble doesn't mean the EQ has a flat response. All that matters is that it sounds right to you.

As for the EQ in teh loop, no idea.

The Pres and Res controls however vary in effect in proportional the lovel the master volumes are set. Those are Negative Feedback based controls and rely on feeding a signal back from your speaker output into the end of the preamp. If your master settings are low, the signal back from the speaker is low, the pres and res are less sensitive and need to be turned up for the same effect they would have at louder master setting. If you crank the amp you need to adjust those controls because more signal will be going through them. The resonance would make your rig sound flubby and the presence will be adding tonnes of treble. You'll probably get crazy feedback from all the treble etc.

 . . . well said !


;)