Tube rolling the Baby Black Beauty or CF amps

[MRHP]

When setup in mono block config, some amps leave one of the two 12ax7's at idle. Can someone give me an idea how to test and see if the Baby Black's are like this....without blowing up anything!!!LOL

[TNRabbit]

They would almost certainly have to be the same way; you only have input on one side, so the other tube would be unused. If you're worried about even wear, switch inputs occasionally~

[mbskeam]

Ummmm.
this amp uses both small tubes.
the toggle acts the same as a Wye cable
what you end up with is both sets of el84 tubes working as 4 instead of 2....

a quick test, pull one of the small tubes when in mono.

[TNRabbit]

Mike, do the Baby Black Beauties have a toggle? Not all the CF amps do....in fact, I'd wager that most don't.

[mbskeam]

yes the real production amps have a toggle switch as to the cf amps I dont have a clue who has done this or not, wye cables are much simpler....

[MRHP]

Ummmm.
this amp uses both small tubes.
the toggle acts the same as a Wye cable
what you end up with is both sets of el84 tubes working as 4 instead of 2....

a quick test, pull one of the small tubes when in mono.

just pull it out with the amp running?

[mbskeam]

no, turn it off, pull 12ax7 tube, then on.

[Magnaryder]

yes the real production amps have a toggle switch as to the cf amps I dont have a clue who has done this or not, wye cables are much simpler....

Mike, I included a bridging switch on my CF amps. I talked Angelo out of a couple of them. They work great and I'm not messing with Y cables. I had an issue with them before.

ray

[radioeng2]

When setup in mono block config, some amps leave one of the two 12ax7's at idle. Can someone give me an idea how to test and see if the Baby Black's are like this....without blowing up anything!!!LOL

I might be wrong, but what I think you're referring to is that while these and most small signal tubes are two triodes, some designs only use one of the triodes in the tube envelope.

In these, that is not the case. One half is used as input voltage gain, the second half as the phase splitter for each channel. So two small signal tubes are being used for a stereo amp. When you're mono-blocking by driving both channels either through a Y cable or physically through a switch, you are still using both channels input sections, so nothing is hanging unused.

Mark

[MRHP]

When setup in mono block config, some amps leave one of the two 12ax7's at idle. Can someone give me an idea how to test and see if the Baby Black's are like this....without blowing up anything!!!LOL

I might be wrong, but what I think you're referring to is that while these and most small signal tubes are two triodes, some designs only use one of the triodes in the tube envelope.

In these, that is not the case. One half is used as input voltage gain, the second half as the phase splitter for each channel. So two small signal tubes are being used for a stereo amp. When you're mono-blocking by driving both channels either through a Y cable or physically through a switch, you are still using both channels input sections, so nothing is hanging unused.

Mark

Thanks Mark, thats what I needed to know.

[Magnaryder]

Mark, the pic you use for your avatar is way cool.

ray

[radioeng2]

Mark, the pic you use for your avatar is way cool.

ray

Thanks Ray. I use it as reminder that one little slip and any of us could have that view. As per Harry.

[hewlew1]

LMAO I am glad to see that remark did not slip by you.

[stevek]

FYI,
Cyber Monday sale at tube depot 6am-noon cst. No connection, never bought from them, I'm just a bargain hunter.
Steve

[radioeng2]

Thanks for pointing this sale out Steve!

Tube Depot is in Memphis. I've ordered from them a couple times and they were flawless transactions. Prompt delivery as I recall. Haven't interacted with them other than web orders so can't comment beyond my experience. Seems to me to be a safe company to deal with.

http://www.tubedepot.com/

Mark