SweetBluez

[tubenit]

Another amp idea DRAFT.  Haven't built it but would love to.  If someone builds this, please give us a review.

Note that it has some topology similar to a Princeton Reverb without tremolo, reverb ............ and is cathode biased with PPIMV.

Compare schematic with layout. Schematic should be "correct".

CHECK for errors!   NOTE Sluckey's post below about the blocking cap, please!

With respect, Tubenit

[TIMBO]

Hey Tubenit, You have come to the rescue of my sanity again. This build I doing has no real direction and I feel that it is not that great, I can get it to a good sound if you want a great overdriven lead sound (does Gary Moore well) but that is about it even the clean channel sounded dull and boring.

My PT is putting out 306v on each leg so that fits your PT. I have three preamp sockets + one for the PI
I have 6V6s as the PT is a little shy on the mAs but the wattage is good for me also has fixed bias
SS rectifier but could add tube rect if required
Has PPIMV installed

The possible changes would be to have a full PI (two halves of a tube) which will leave me with a spare half tube

I 'll leave it at that the wifes calling me for dinner. Thanks

[tubenit]

Timbo,

I would love to have you build this and report back. IF I ever build another amp for myself, I think this will be the one.  My gut level feeling is that it's gonna be a sweet sounding amp!

Best regards, Tubenit

[sluckey]

Jeff, you need to put a blocking cap on the grid of the PI tube to prevent upsetting or outright killing the bootstrapped bias on the grid. There will be a healthy positive dc voltage on that grid.

[tubenit]

Steve,

THANKS for catching that!!!

Jeff

[TIMBO]

Hi guys, This is what I have come up with, all tubes used 

The PSU on sheet 2 is what I have now, so I think that I will start with it as is (other that changing the dropping resistors as required)

I'll also leave the components around the power tubes as is for now.

I do have a 5Y3GT, I think a tube rect would be best 

What cap would I require for Sluckeys catch?

Best place to insert REVERB? I was wondering if it could be placed IN the FX loop just after the SEND LEVEL pot  or before V3a 

Thanks 

[tubenit]

What about paralleling the reverb with the FX loop?    

OR ................. just FX and vibrato ................. OR reverb and vibrato?   And if you want vibrato and need help with layout, just let me know.   I think it might be cool to have FX with vibrato and then you can use either or both delay and reverb in the active FX loop. Plus the
FX loop still serves as a Master volume.

With respect, Tubenit

[sluckey]

What cap would I require for Sluckeys catch?

.01, .022, .047, etc. It's not critical.

[TIMBO]

Hi guys, I have been able to rework the layout to suit the tube location I have and its fitted well. I going with the reverb paralleled and I think it will be an easy change if required

I'm going to leave the SS rect as is for the moment.

I'm not going the add a vibrato as it is not something I use, but thanks for the input

Looking forward to the build. Thanks 

[tubenit]

Working on an "alternative" layout to Timbo's that has the FX send and reverb Dwell on the back of the amp chassis. Those are both set and forget for me.

Also my personal preference is to have FX within one tube and Reverb within one tube.

Layout is one the 3rd sheet.

CHECK for errors!  This was a complicated layout to draw up.  IF there is an error, go with the schematic.

Not necessarily better than Timbo's, just different & another way to approach it.

With respect, Tubenit

[TIMBO]

Thanks T, It is a difficult one to layout and I would rather have a tube for each FX.  ...........................

[tubenit]

Please double and triple check it IF you're considering using it. 

I drew it up .......... glanced over it and posted it without a thorough looking over.  I think it's correct but not totally positive?

IF you find an error and edit it ............ please repost it & I'll delete the version I posted.

With respect, Tubenit

[moonbird]

tubenit -


I have been looking at your vibrato wanderings the past few day and happened on this idea. Looks very cool and similar in size to the PR I was considering. Anywho - I have always wanted to try that Dano 6au6 vibe you built a while back. Would there be any trick to using it in this circuit? I would probably be most interested in the reverb/vibrato version. Sorry to bump an old thread. Thanks kindly.

[tubenit]

I think the 6Au6  Dano Centurian vibrato (which is the pretty much the same as the Silvertone 1482) would work fine in this build.  It is the best sounding vibrato I've heard on an amp, IMO.

With respect, Tubenit

[moonbird]

tubenit -


Great - thx much for the reply!