Rocket Reverb ... low output

[davesi]

Followed with great interest the Express problem thread as I have similar symptons with a Reverb Rocket build. Everything works but low distorted output. I am attaching schematic and voltage chart I am working from and a few pics. The layout is basically Normsters layout.

I have tried to eliminate the usual suspects... tubes, cables, speakers, connectivity, grounds... to identify the problem and suspect it may be in the reverb circuit. After going through the layout several times, I sent an audio track through the input and attempted to trace th AC voltage through the stages.

Here is averaged measurements with ALL controls at 50%:

V1b Pin 7 = 0.06 VAC
V1b Pin 6 = 0.002 VAC

V1a Pin 2 = 0.2 VAC
V1a Pin 1 = 3.6 VAC

V2b Pin 7 = 3.5 VAC
V2a Pin 2 = 0.02

v3ab Pin 2 = 0.02 VAC

V4a Pin 2 = 0.02 VAC
V4b Pin 7 = 0.4 VAC

Reveb wiring is mostly under the board and with the exception of miscolored plugs seems correct to me. I am hopeful there is a simple blunder in the wiring on my part ,but I can't find it. Reverb tranny is specified as 22.8K ohms primary, 8 ohms secondary, I tried to measure this in the circuit (don't know if this is possible) and measured 1.065K & 1.5 ohms.

I would be most greatful for any suggestions/corrections or thoughts. Thanks

Dave

[M Fowler]

I reviewed your wiring and I did not seen any errors. I am suspecting the OT.

[Randy Magee]

Must be a rash going around...

[davesi]

Thanks Mark, I appreciate all you do for for the community. I have a 6.6k Deluxe OT around here somewhere, I suppose I will disconnect existing OT primaries and secondaries and tack it in to try to verify as suggested in other thread. Would OT cause apparent signal loss through reverb circuit?

Thanks

[ampmike]

Just had to comment on the heater wires.Thats the same 2 colors I use.Looks great!!!I had to post that, when I saw your pics I did a double take.Nice looking build,very tidy!
Good luck Man,Mikey

[davesi]

Thank you ampmike. OK, think I found it. Had an itty bitty 6.6K BJ OT around so I disconnected existing OT B+2 and secondaries and plugged in this miniscule OT...B+2, tacked in plates, connected secondaries to ext speaker jack and....SOUND!!! I've never heard a Rocket before!!!, and with this pathetic little piece of iron....speachless. Much more bass than I expected.

There was a thread a while back regarding what great vendors we have on this board. Damn right! I have not found a finer gentleman anywhere than rj, and want you all to know this issue is resolved! Can't wait for the real thing!

Was going to wait until I had everything together before posting these pics but now that I know...

Thanks rj...., Thanks Taylor for the beatiful headshell...Thanks to TAG, I learned everything neccessary to build this beautiful amp right here.

Dave

[davesi]

Installed new OT on sunday....this amp is amazing!

[M Fowler]

Great news. Are you using the medium decay short tank? I love the subtle reverb my reverb rocket has.

[pablogt]

Congrats, great job... How did you fit the tank inside the cab? Is it fixed to the top panel of the cabinet or inside a bag? Do you think a long delay tank like 9AB3C1B would fit in there?

Pablo

[davesi]

Yes Mark, the 8AB2D1A short tank for mounting to the top. I wanted the suble reverb too, even used a 100K reverb pot. Have just done a dry fit...as far forward as it will go like on your build. Tank dimensions are approx. 1.5" X 9.25". This should place the nearest edge of tank about 05" forward and 1.5" above nearest preamp tube. NO hum whatsoever outside of head shell. Hope it is that quite when installed. Never considered long tank. On my layout it may be too close to PT for comfort..or even fit.

Dave

[M Fowler]

Great to hear your amp is working out so well.

I get no noise from mine at all which I am very pleased about.