Tweed BluezMeister with active FX loop-mods on capacitors

[adamG]

Mr T.

Just because of my last glory which is Geezer's Bluezmeister build  ,I get started consideration of Mr T.version - 6V6 combo.
I like mids tonal character on preamp stage, so I would provide 0,022uF caps there.
Also, it's tempting me to change 0,033uF to 0,022uF in power stage.
Do you think it's a good idea?
Preferable HT on 6V6 is over 400V. Do you advice me to keep 374V on nod A, or may I increase anode voltage above 400V to receive more power?
Is it worth of efforts, or with voltage increasing I'd lost its tonal beauty?
Another challenge for me is to get started playing with FX stage. Many men judge it as common beauty onboard. So, it is a time play with:)

Thank you in advance.

Regards,

Adam
 
 

[tubenit]

Regarding cap values,  I recommend experimenting with different values and taking your time with it.  Once you think you've got a value you like, play it for a week or two before making a final decision.

I've become partial to PT's that have 300-0-300  and at least 140ma.  And then use cathode biased.

With that I can use a 5y3GT   300 X1.1 = 330v on plates
OR  a 5V4                             300 x 1.2 = 360
OR a GZ34                            300 X 1.3 = 390
or a solid state rectifier plug   300 X 1.4 = 420v

With those different voltages,  I have played 6K6 (330v not sure how long they'd hold up at that voltage), 6V6 at any of those voltages or 6L6 at any of those voltages for all kinds of tonal variations. 

IF I were picking one voltage and not varying it,  it would be 390v with 5881's/6L6  (or 6V6.s).

I like having an active FX loop on board.  But I always play with either a delay pedal or reverb pedal in the FX.

With respect, Tubenit

[adamG]

Tubenit,

Thank you:)
Two more questions, if you please?
Does FX loop work ok without a pedal? I used to plug a reverb into, but not always.
Second one is, could you briefly explain those two options of 6L6 and 6V6 tubes altered each other?
Does OT need taps for 4K and 8K ?

Thank you in advance.

Regards,

Adam

[tubenit]

I would say the amp sounds great with a delay or reverb in FX loop and the FX works just "OK" without a pedal.  I would install a DPDT mini-toggle to bypass the FX loop if you're not using it.

I don't change anything in bias or impedence switching between tubes.  Simply swap tubes and play.

With respect, Tubenit

[adamG]

Tubenit,

As always, thank you!

How about missing/reduced MV in case of FX switched off?
Should I go back to MV onboard or FX will work fine without a pedal in ?

Regards,

Adam

[tubenit]

Adam,

I am not sure how to answer your question?  Yes, the FX works "fine" or "OK" with the pedal in the loop.  I so strongly prefer delay in the signal that it just sounds "OK" without delay to my ears.  But yes, the FX certainly works without a pedal.

IF you are concerned about wanting to eliminate the FX loop and have a master volume pre phase invertor, then I would increase the FX level pot (which serves as the master volume) to 500ka and then put in a DPDT switch.

With respect, Tubenit

[adamG]

Tubenit,

Thank you very much!
Smart solution with this MV pot
One question more. Are you sure about these 6L6 tubes on power stage?
Maybe another one I have, sorry. Caps 0,05 and 0,04 aren't available in my place. I am going to swap them with 0,047. Is that ok?

Regards,

Adam

[tubenit]

I have JJ 6L6 tubes in the Tweed BluezMeister.  There are a number of 6V6's that you could use also that will hold up well at or under 400v.  With a PT of 140ma or more, one can simply switch between 6L6/5881 or 6V6's without having to rebias.   

Yes, I would just use .047 & I think that will be fine.

Remember if you ever need an odd size that you can parallel caps.  Such as a .022 and a .01 to make a .032.

With respect, Tubenit

[PRR]

> Remember if you ever need an odd size...

...then remember this is Audio, R-C filters are gentle, +/-30% is usually no-difference.

If a "known good" value is say 0.047, then 0.036 to 0.061 will probably sound all the same. Or pretty-near. And certainly close enough to play until you can order-in some odd values to try.

Remember that ALL older amp caps were +/-20% tolerance. 10% and 5% did not get affordable until recent decades.

0.04, 0.05, and 0.047 are mostly artifacts of how part numbers are "rationalized". That's a complicated concept which has been re-specified every few decades, and has ended up in some "funny looking" numbers like 39 and 47.

Just use what is close.

[adamG]

Big thanks to both of you gents!

Regards,

Adam