Short version: they are interchangeable in 99.999% of situations.Thank for reply
I really don't know about the DC heater or property done AC,
Short version: they are interchangeable in 99.999% of situations.Thank for reply
I really don't know about the DC heater or property done AC,
SIY thank UShort version: they are interchangeable in 99.999% of situations.
This is the way. Better and cheaper than vintage tracers. Unsurprisingly, lots of tube 'experts' swear by vintage gear that performs worse.Hmmz. Surfing how to parallel tube amp output tubes and found a curve tracer assembled kit and vacuum tube tester.
Yes, and no CRT screenshots made with 35mm camera gear and a hood. It's pure PC based. For reaLZ!This is the way. Better and cheaper than vintage tracers. Unsurprisingly, lots of tube 'experts' swear by vintage gear that performs worse.
Admittedly I am a little jealous of people who got to cherry pick gear from old lab cleanout day. I would love to play around with this stuff if some of it fell in my lap.Yes, and no CRT screenshots made with 35mm camera gear and a hood. It's pure PC based. For reaLZ!
Behold... A oscilloscope camera for a Tektronix O-scope.
I've handled some of the Tektronix camera gear on 7000 series scopes for demonstration and getting a look at how it all looked and it's all beasty equipment. No pictures taken just assembled the gear and checked it out.Admittedly I am a little jealous of people who got to cherry pick gear from old lab cleanout day. I would love to play around with this stuff if some of it fell in my lap.
I think that was a polaroid camera back. I never actually used one but that's my memory.Yes, and no CRT screenshots made with 35mm camera gear and a hood. It's pure PC based. For reaLZ!
Behold... A oscilloscope camera for a Tektronix O-scope.
Could be. I know very little about camera gear. To me it was big, chunky, metal.. arrgH heavy...I think that was a polaroid camera back. I never actually used one but that's my memory.
The 12AX7A has a different filament configuration (spiral wound) to reduce noise and/or hum.Hello all member
I am newbee, I need some help about my McIntosh C8 tube preamp, I want to buy new tubes for C8, but the stock tube have letter A at end of tube modelname ( 12AX7A ), and all tubes on market no letter A on it ( 12AX7 )
question is can I buy tube 12AX7 without letter A and use on C8 ?
Thank you all
mhardy6647: Thank youThe 12AX7A has a different filament configuration (spiral wound) to reduce noise and/or hum.
There are reports on the internet that the unsuffixed version can only be used with parallel filament circuits, while the "A" morph can be used with series or parallel filament circuits, but I am not at all sure that is true. That said, generally speaking*, the "A" suffix referred to a tube with a controlled heater warm up time, which is (more or less) required for series filament strings, and tubes like the 12AX7 were occasionally (OK, more than occasionally!) used in transformerless (!), so called "AC-DC" series string filament electronic equipment. Such designs were rightly known, even when they were common in consumer products, known as "killer" circuits. With a nonpolarized AC mains plug, there was a 50-50 chance of the chassis being "hot" (i.e., directly connected to the hot side of the AC supply).
The two spec sheets above from RCA's HB-3 reference are pretty much "Gospel".
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* always remember: all generalizations are false, including this one.
So... yes... assuming your Mac doesn't have a series filament string.mhardy6647: Thank you
I am not pro to understand what you wrote, thank you anyway
Just ask if anyone know can replace 12AX7 to 12AX7A ( stock tubes on McIntosh C8 Preampplifier ?
Thank bro Have a good weekend
If in doubt, I'd just use the "A" spec ones.mhardy6647: Thank you
I am not pro to understand what you wrote, thank you anyway
Just ask if anyone know can replace 12AX7 to 12AX7A ( stock tubes on McIntosh C8 Preampplifier ?
Thank bro Have a good weekend
I want to try this :So... yes... assuming your Mac doesn't have a series filament string.
Which is a pretty darned safe assumption.
No good reason to do so, though. The "A" tubes should peform a little better in terms of S/N.
Do you have specific tubes in mind?
I try to looking around, don't see any store have 12AX7A, maybe it has different nameIf in doubt, I'd just use the "A" spec ones.
ECC83I try to looking around, don't see any store have 12AX7A, maybe it has different name
here the ones I want to buy, but it haven't letter"A"ECC83
I'm sure they will be fine.here the ones I want to buy, but it haven't letter"A"
Genalex Gold Lion 12AX7 tube (ECC83)
thank UI'm sure they will be fine.