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Alain is offering 10% off all tubes if you bring your tube amp in for retubing in the month of September.

What about "retubing" microphones?

Malcolm Boyce wrote:What about "retubing" microphones?

Same thing. You might be charged a 10% aggravation fee though...

LOL!

Malcolm Boyce wrote:What about "retubing" microphones?

Yes microphones as well.
Not so much due to tube life being expended but often more for tonal improvements.

Al, you got any 5751 tubes?

I believe so. I'll check Tomorrow and get back to ya.

A.

BTW, care to share with us why you require a 5751 specifically?

A.

I have an NIB Sovtek 5751!

Alain Benoit wrote:BTW, care to share with us why you require a 5751 specifically?

Experimenting with lowering the send level of effects loop of my guitar amp. Also, going to try different tubes in the phase-inverter position. I will PM you regarding $.

I figured it was something like that.
A 5751 as you know has a gain factor of 70, you may also want to try a 12AT7 which has a gain factor of 60.
My favourite tube in the PI position is the Sovtek 12AX7 LPS.

The 5751 didn't lower the send level at all. What was in there was an Electro-Harmonix 12AX7. I expect to soon be aquiring a 12AY7 that I will try.
And next I will write of trying different tubes in preamp tube one position.

Al,
I plan on trying a Sovtek 12AX7 LPS in the Phase Inverter position. My understanding is that (especially) for the PI, how well the tube is matched to itself can make a significant difference in how the amp performs. What are your thoughts on this and do you have said tube(tested?) in your inventory?

My default tube in the PI position is the LPS.
This is based on testing and experience.

The triodes should be matched well here as you say or crossover distortion could be introduced, that being said, not having your output tubes perfectly matched and biased will overshadow this factor by a fair margin.

Yes I do stock Sovtek 12AX7 LPS'.

A.

Alain Benoit wrote:not having your output tubes perfectly matched and biased will overshadow this factor by a fair margin.

My amp is cathode-biased. Does that make it less critical that power tubes are perfectly matched?
and
Your Sovtek 12AX7 LPS's, (in regard to the triodes being well matched), do you:
-test them yourself?
-feel confident that your source adequately tests them?
-trust that all the Sovtek 12AX7LPS's leaving the factory(s) are up to snuff in this respect?
If not, are you willing/able to perform the necessary testing?
and
Do you still have a set of THD Yellow Jackets? What type are they? YJ20, YJCD, other?

Hope you don't mind all the questions. Take your time.

Scott DeVarenne wrote:

Alain Benoit wrote:not having your output tubes perfectly matched and biased will overshadow this factor by a fair margin.

My amp is cathode-biased. Does that make it less critical that power tubes are perfectly matched?

NO.

Scott DeVarenne wrote:and
Your Sovtek 12AX7 LPS's, (in regard to the triodes being well matched), do you:
-test them yourself?
-feel confident that your source adequately tests them?
-trust that all the Sovtek 12AX7LPS's leaving the factory(s) are up to snuff in this respect?
If not, are you willing/able to perform the necessary testing?

b)

Scott DeVarenne wrote:and
Do you still have a set of THD Yellow Jackets? What type are they? YJ20, YJCD, other?

Hope you don't mind all the questions. Take your time.

They are the ones designed for use with the 6V6 circuits.

A.