[Shhhh!!!! I'm Listening to Reason!]

Could you provide me with a list of tubes that were specifically
designed for audio? I'm finding that very, very few of the tubes used
in audio circuits were designed with audio in mind.

TIA!

[Boon[_2_]]

On Jul 12, 1:01*pm, "Shhhh!!!! I'm Listening to Reason!"
wrote:
Could you provide me with a list of tubes that were specifically
designed for audio? I'm finding that very, very few of the tubes used
in audio circuits were designed with audio in mind.

TIA!

LoL!

[Shhhh!!!! I'm Listening to Reason!]

On Jul 12, 2:32*pm, Boon wrote:
On Jul 12, 1:01*pm, "Shhhh!!!! I'm Listening to Reason!"

wrote:
Could you provide me with a list of tubes that were specifically
designed for audio? I'm finding that very, very few of the tubes used
in audio circuits were designed with audio in mind.

TIA!

LoL!

Well, so far I find that unless an amp uses 6L6, EL34, 2A3 or a few WE
numbers, or 6BQ5 (or variants thereof) for outputs it ain't using
audio tubes, people!

And the signal tubes better be 6267, 6EU7, 5879 or ECC808 or a very
few others or they ain't using audio tubes, people!

None of the rectifier tubes were designed with audio in mind. Even
then the audio market was small potatoes compared to the industrial
market at large.

McIntosh and Marantz were the worst offenders using tubes like 6DJ8,
6CG7/6FQ7, 6550 and other NON-AUDIO tubes in their circuits.
Ironically they are among the most sought out by collectors.

Note to 2pid: I am killing you on audio-related posts this year.
You're at what, zero? LoL.

[Bret L]

****ter:


wrote:
Could you provide me with a list of tubes that were specifically
designed for audio? I'm finding that very, very few of the tubes used
in audio circuits were designed with audio in mind.

TIA!

LoL!

Well, so far I find that unless an amp uses 6L6, EL34, 2A3 or a few WE
numbers, or 6BQ5 (or variants thereof) for outputs it ain't using
audio tubes, people!

And the signal tubes better be 6267, 6EU7, 5879 or ECC808 or a very
few others or they ain't using audio tubes, people!

None of the rectifier tubes were designed with audio in mind. Even
then the audio market was small potatoes compared to the industrial
market at large.

McIntosh and Marantz were the worst offenders using tubes like 6DJ8,
6CG7/6FQ7, 6550 and other NON-AUDIO tubes in their circuits.
Ironically they are among the most sought out by collectors.


"Designed for audio" means different things in different contexts,
i.e, whether one is talking about small signal or power tubes, and as
opposed to general purpose tubes or tubes specifically designed for
other purposes. In some cases tubes specifically designed for other
applications work quite well in audio applications and in others not
so well.

In the case of power tubes, specifically audio types differ from RF
output, TV horizontal deflection, and voltage regulator tubes in
several areas. Linearity is at a premium, plate caps are undesireable,
and operating the screen grid at close to full anode voltage is a
design simplifier. In the case of triodes, the mu or amplification
factor should be high enough for easy driving but low enough to permit
the range of voltage swing to stay well over ground. On the other hand
really rugged plate structures, desireable in pi-section coupled RF
amplifiers to permit tuning by plate color is not really needed.

The 6DJ8 was specifically designed to be operated in cascode and
works well in that application. It is not generally considered an
"audio tube" but works well in some audio circuits. The only Marantz
amplifier app is the not great sounding Model 9 AFAIK.

The 6550 was an audio tube and nothing but. Where you got that from I
have no idea.

In the case of rectifier tubes there never was any reason to design
one specifically for audio.

It's worth mentioning that the hi-fi market at its peak (the JFK/MM
era more or less) was indeed lucrative and many power and signal tubes
were specifically designed for those markets. Many of those specific
designs were never all that popular as they did little to improve on
the old standbys in the minds of designers.

Some very good audio products use tubes not designed for audio but so
do a lot of ****ty ones. And some using only purpose designed audio
tubes are pretty bad.

The best thing to do to determine what are "audio tubes" is to read a
tube manual. Unfortunately, tube audio does attract some illiterate
people, and others simply too stupid to make sense of the information
found therein. The next step is to study some classic circuits and
commentary thereon. Many good print references exist. However, the
same issue applies there too.

[Shhhh!!!! I'm Listening to Reason!]

On Jul 12, 6:59*pm, Bret L wrote:
****ter:







wrote:
Could you provide me with a list of tubes that were specifically
designed for audio? I'm finding that very, very few of the tubes used
in audio circuits were designed with audio in mind.

TIA!

LoL!

Well, so far I find that unless an amp uses 6L6, EL34, 2A3 or a few WE
numbers, or 6BQ5 (or variants thereof) for outputs it ain't using
audio tubes, people!

And the signal tubes better be 6267, 6EU7, 5879 or ECC808 or a very
few others or they ain't using audio tubes, people!

None of the rectifier tubes were designed with audio in mind. Even
then the audio market was small potatoes compared to the industrial
market at large.

McIntosh and Marantz were the worst offenders using tubes like 6DJ8,
6CG7/6FQ7, 6550 and other NON-AUDIO tubes in their circuits.
Ironically they are among the most sought out by collectors.

* "Designed for audio" means different things in different contexts,

No, it means the tube was designed with audio as the primary purpose.

i.e, whether one is talking about small signal or power tubes, and as
opposed to general purpose tubes or tubes specifically designed for
other purposes. In some cases tubes specifically designed for other
applications work quite well in audio applications and in others not
so well.

That makes no difference, people.

*In the case of power tubes, specifically audio types differ from RF
output, TV horizontal deflection, and voltage regulator tubes in
several areas. Linearity is at a premium, plate caps are undesireable,

Tell that to McIntosh, who used 6BG6 tubes with great success. Yes,
it's similar to 6L6 tubes. However, they used these tubes even though
6L6 tubes were as cheap and (perhaps) more plentiful.

snip autistic ramble

* The 6DJ8 was specifically designed to be operated in cascode and
works well in that application. It is not generally considered an
"audio tube" but works well in some audio circuits. The only Marantz
amplifier app is the not great sounding Model 9 AFAIK.

*The 6550 was an audio tube and nothing but. Where you got that from I
have no idea.

That is irrelevant to the main point: that non-audio tubes make an amp
"phooey".

Add the 5687 to the list.

*In the case of rectifier tubes there never was any reason to design
one specifically for audio.

*It's worth mentioning that the hi-fi market at its peak (the JFK/MM
era more or less) was indeed lucrative and many power and signal tubes
were specifically designed for those markets. Many of those specific
designs were never all that popular as they did little to improve on
the old standbys in the minds of designers.

Are you on drugs? I never said it wasn't a viable market. I said it
was small potatoes as far as tube usage to industrial applications.
What a moron.

*Some very good audio products use tubes not designed for audio but so
do a lot of ****ty ones. And some using only purpose designed audio
tubes are pretty bad.

And some are pretty good. Since you didn't bother to listen to the BAT
amp you'll never know and you are therefore entirely unqualified to
make the statement you made.

I already knew that. Now you do too.

*The best thing to do to determine what are "audio tubes" is to read a
tube manual.

Wrong. Tube manuals do not state why the company that developed a tube
developed it. A tube manual does not even tell you what company
developed a particular type. Therefore you cannot tell what tubes were
developed for audio from a simple tube manual.

I do have a fairly rare government manual that will tell you that
information but I don't have it with me.

Anyway, it was fun to make an ass of you, Bratzi. Thanks for playing.
LoL.

[Bret L]

None of the rectifier tubes were designed with audio in mind. Even
then the audio market was small potatoes compared to the industrial
market at large.

McIntosh and Marantz were the worst offenders using tubes like 6DJ8,
6CG7/6FQ7, 6550 and other NON-AUDIO tubes in their circuits.
Ironically they are among the most sought out by collectors.

* "Designed for audio" means different things in different contexts,

No, it means the tube was designed with audio as the primary purpose.

I mean, penishead, that a small signal tube is optimized for audio in
a different way than a power output tube. For example the heater
connections may be changed to reduce hum, important in preamps and
power amp first stages, irrelevant in a power tube.

i.e, whether one is talking about small signal or power tubes, and as
opposed to general purpose tubes or tubes specifically designed for
other purposes. In some cases tubes specifically designed for other
applications work quite well in audio applications and in others not
so well.

That makes no difference, people.

*In the case of power tubes, specifically audio types differ from RF
output, TV horizontal deflection, and voltage regulator tubes in
several areas. Linearity is at a premium, plate caps are undesireable,

Tell that to McIntosh, who used 6BG6 tubes with great success. Yes,
it's similar to 6L6 tubes. However, they used these tubes even though
6L6 tubes were as cheap and (perhaps) more plentiful.

Only on one, obscure industrial model

http://mcc.berners.ch/power-amplifiers/A116.pdf

This tube was identical to the 6L6 except for pin out...
http://www.vacuumtubes.com/6BG6.html

* The 6DJ8 was specifically designed to be operated in cascode and
works well in that application. It is not generally considered an
"audio tube" but works well in some audio circuits. The only Marantz
amplifier app is the not great sounding Model 9 AFAIK.

*The 6550 was an audio tube and nothing but. Where you got that from I
have no idea.

That is irrelevant to the main point: that non-audio tubes make an amp
"phooey".

These specific tubes tend to do that based on hundreds of DIY and
small company products that are a pain in the ass.

*It's worth mentioning that the hi-fi market at its peak (the JFK/MM
era more or less) was indeed lucrative and many power and signal tubes
were specifically designed for those markets. Many of those specific
designs were never all that popular as they did little to improve on
the old standbys in the minds of designers.

Are you on drugs? I never said it wasn't a viable market. I said it
was small potatoes as far as tube usage to industrial applications.
What a moron.

Are you smoking your tampon? Industrial was never that high a
volume.

*Some very good audio products use tubes not designed for audio but so
do a lot of ****ty ones. And some using only purpose designed audio
tubes are pretty bad.

And some are pretty good. Since you didn't bother to listen to the BAT
amp you'll never know and you are therefore entirely unqualified to
make the statement you made.

I already knew that. Now you do too.


I did not say the BAT has to suck, but that it uses a tube that is
bad practice to audio for audio in general.

*The best thing to do to determine what are "audio tubes" is to read a
tube manual.

Wrong. Tube manuals do not state why the company that developed a tube
developed it. A tube manual does not even tell you what company
developed a particular type. Therefore you cannot tell what tubes were
developed for audio from a simple tube manual.

Look at the description. AUDIO POWER AMPLIFIER, HORIZONTAL DEFLECTION
AMPLIFIER, and RADIO FREQUENCY POWER AMPLIFIER are pretty self
explanatory. You can ALSO read the audio specific literature such as
RCA's HF-110 circular.

[Shhhh!!!! I'm Listening to Reason!]

On Jul 13, 1:36*pm, Bret L wrote:
None of the rectifier tubes were designed with audio in mind. Even
then the audio market was small potatoes compared to the industrial
market at large.

McIntosh and Marantz were the worst offenders using tubes like 6DJ8,
6CG7/6FQ7, 6550 and other NON-AUDIO tubes in their circuits.
Ironically they are among the most sought out by collectors.

* "Designed for audio" means different things in different contexts,

No, it means the tube was designed with audio as the primary purpose.

*I mean, penishead, that a small signal tube is optimized for audio in
a different way than a power output tube. For example the heater
connections may be changed to reduce hum, important in preamps and
power amp first stages, irrelevant in a power tube.

Therefore the 7025 is the only 12AX7 variant designed with audio in
mind. Any company that uses a standard 12AX7 is "phooey".

i.e, whether one is talking about small signal or power tubes, and as
opposed to general purpose tubes or tubes specifically designed for
other purposes. In some cases tubes specifically designed for other
applications work quite well in audio applications and in others not
so well.

That makes no difference, people.

*In the case of power tubes, specifically audio types differ from RF
output, TV horizontal deflection, and voltage regulator tubes in
several areas. Linearity is at a premium, plate caps are undesireable,

Tell that to McIntosh, who used 6BG6 tubes with great success. Yes,
it's similar to 6L6 tubes. However, they used these tubes even though
6L6 tubes were as cheap and (perhaps) more plentiful.

*Only on one, obscure industrial model

Did I say otherwise?

http://mcc.berners.ch/power-amplifiers/A116.pdf

*This tube was identical to the 6L6 except for pin out...http://www.vacuumtubes.com/6BG6.html

So why did they use a horizontal deflection tube? McIntosh is clearly
"phooey".

* The 6DJ8 was specifically designed to be operated in cascode and
works well in that application. It is not generally considered an
"audio tube" but works well in some audio circuits. The only Marantz
amplifier app is the not great sounding Model 9 AFAIK.

*The 6550 was an audio tube and nothing but. Where you got that from I
have no idea.

That is irrelevant to the main point: that non-audio tubes make an amp
"phooey".

*These specific tubes tend to do that based on hundreds of DIY and
small company products that are a pain in the ass.

I have a supply of a tube called a 6384. It works quite well. Others
agree. Ditto EL38, 12E1 and the others I mentioned earlier.

You (and GOIA) claim technical expertise is a prerequsite in your
worlds to be an audiophile. Now you abuse those who have it. Make up
your mind, numbnuts. LoL.

*It's worth mentioning that the hi-fi market at its peak (the JFK/MM
era more or less) was indeed lucrative and many power and signal tubes
were specifically designed for those markets. Many of those specific
designs were never all that popular as they did little to improve on
the old standbys in the minds of designers.

Are you on drugs? I never said it wasn't a viable market. I said it
was small potatoes as far as tube usage to industrial applications.
What a moron.

*Are you smoking your tampon? Industrial was never that high a
volume.

LOL! It was a far higher volume and with far more usage than audio.
And an audio amp would get usage that might require switching tubes
every few years. Industrial switches and other machinery (not to
mention the military) would switch tubes out far more frequently.

TVs used far more tubes and had far higher turnover. Audio was not as
big in consumer electronics as TVs.

*Some very good audio products use tubes not designed for audio but so
do a lot of ****ty ones. And some using only purpose designed audio
tubes are pretty bad.

And some are pretty good. Since you didn't bother to listen to the BAT
amp you'll never know and you are therefore entirely unqualified to
make the statement you made.

I already knew that. Now you do too.

*I did not say the BAT has to suck, but that it uses a tube that is
bad practice to audio for audio in general.

I'll bet that amp sounds great.

*The best thing to do to determine what are "audio tubes" is to read a
tube manual.

Wrong. Tube manuals do not state why the company that developed a tube
developed it. A tube manual does not even tell you what company
developed a particular type. Therefore you cannot tell what tubes were
developed for audio from a simple tube manual.

*Look at the description. AUDIO POWER AMPLIFIER, HORIZONTAL DEFLECTION
AMPLIFIER, and RADIO FREQUENCY POWER AMPLIFIER are pretty self
explanatory. You can ALSO read the audio specific literature such as
RCA's HF-110 circular.

Perfect. Go through your tube manual and tell me how many are audio
specific. Then seperate out the power tubes from the signal to see a
REALLY small number. My RC-12, RC-30, and Mullard, Sylvania and other
tube manuals are in storage or I'd do it for you. But I already know
the answer. I even have a rare book from Phillips on tubes for audio.

I'll bet that as a percentage of the total tubes listed the audio-
specific types are at 5% or (probably) less.

As I recall most of the the 12A*7 series are not audio tubes. The only
audio-specific signal tubes I recall are 6267, 5879, 7199 and 6EU7.

As I said earlier, companies that use 6SN7, 6U8 (Scott used these a
lot), 6GC7/6FQ7, 12A*7 and the like are "phooey".

[John Stone]

On 7/13/10 6:11 PM, in article
,
"Shhhh!!!! I'm Listening to Reason!" wrote:

6U8 (Scott used these a
lot), 6GC7/6FQ7, 12A*7 and the like are "phooey".

6U8 and its cousin 6GH8, both of which were used extensively in tv
applications, are now being used to replace the difficult to find 7199 in
old Dynaco and other gear. Apparently the 7199 was little more than a 6GH8
with different basing and a spec for noise. There are plug in adapters
available or you can just rewire the socket. The subs yield equal or better
specs compared with the original tubes.

[Clyde Slick]

On Jul 13, 8:29*pm, John Stone wrote:
On 7/13/10 6:11 PM, in article
,
"Shhhh!!!! I'm Listening to Reason!" wrote:

6U8 (Scott used these a
lot), 6GC7/6FQ7, 12A*7 and the like are "phooey".

6U8 and its cousin 6GH8, both of which were used extensively in tv
applications, are now being used to replace the difficult to find 7199 in
old Dynaco and other gear. Apparently the 7199 was little more than a 6GH8
with different basing and a spec for noise. There are plug in adapters
available or you can just rewire the socket. The subs yield equal or better
specs compared with the original tubes.

except that a good 6U8 is pretty hard to find, not as scarce as 7199,
but hard to find
a telefunken. Don't much like the GE'S and RCA's nor the 6GH8, except
for Sylvania's
these tubes are used in my Scott integrateds,

[John Stone]

On 7/13/10 7:54 PM, in article
, "Clyde
Slick" wrote:

6U8 and its cousin 6GH8, both of which were used extensively in tv
applications, are now being used to replace the difficult to find 7199 in
old Dynaco and other gear. Apparently the 7199 was little more than a 6GH8
with different basing and a spec for noise. There are plug in adapters
available or you can just rewire the socket. The subs yield equal or better
specs compared with the original tubes.

except that a good 6U8 is pretty hard to find, not as scarce as 7199,
but hard to find
a telefunken. Don't much like the GE'S and RCA's nor the 6GH8, except
for Sylvania's
these tubes are used in my Scott integrateds,

The 7199's were all made by RCA regardless of the labeling. 6U8's and 6GH8's
are still as common as dirt. I bought a pair of NOS 6678 GE (industrial
version of 6U8) for a buck each at a radio meet last weekend. The seller had
piles of them. I had my choice of Sylvania, RCA, GE, Tung Sol, etc. Not
sure why you "don't like" GE's and RCA's. There's absolutely nothing wrong
with them. I wasn't even aware that Telefunken made these tubes. What is the
European number?

[Shhhh!!!! I'm Listening to Reason!]

On Jul 13, 7:54*pm, Clyde Slick wrote:
On Jul 13, 8:29*pm, John Stone wrote:

On 7/13/10 6:11 PM, in article
,
"Shhhh!!!! I'm Listening to Reason!" wrote:

6U8 (Scott used these a
lot), 6GC7/6FQ7, 12A*7 and the like are "phooey".

6U8 and its cousin 6GH8, both of which were used extensively in tv
applications, are now being used to replace the difficult to find 7199 in
old Dynaco and other gear. Apparently the 7199 was little more than a 6GH8
with different basing and a spec for noise. There are plug in adapters
available or you can just rewire the socket. The subs yield equal or better
specs compared with the original tubes.

except that a good 6U8 is pretty hard to find, not as scarce as 7199,
but hard to find
a telefunken. Don't much like the GE'S and RCA's nor the 6GH8, except
for Sylvania's
these tubes *are used in my Scott integrateds,

I found most 6GH8s hummed in the ST-70 circuit I had which is my only
experience with them. That circuit was "phooey". I use Tele 6U8s in my
Scott, they do fine. I have about six more of them NOS.

I had a Dyna ST-70 that I dropped a new board into that used 6GH8s. I
never found one I liked. Amperex and all the other big names, bith US
and Euro, didn't work out very well.

[Shhhh!!!! I'm Listening to Reason!]

On Jul 13, 8:25*pm, John Stone wrote:
On 7/13/10 7:54 PM, in article
, "Clyde

Slick" wrote:

6U8 and its cousin 6GH8, both of which were used extensively in tv
applications, are now being used to replace the difficult to find 7199 in
old Dynaco and other gear. Apparently the 7199 was little more than a 6GH8
with different basing and a spec for noise. There are plug in adapters
available or you can just rewire the socket. The subs yield equal or better
specs compared with the original tubes.

except that a good 6U8 is pretty hard to find, not as scarce as 7199,
but hard to find
a telefunken. Don't much like the GE'S and RCA's nor the 6GH8, except
for Sylvania's
these tubes *are used in my Scott integrateds,

The 7199's were all made by RCA regardless of the labeling. 6U8's and 6GH8's
are still as common as dirt. I bought a pair of NOS 6678 GE (industrial
version of 6U8) for a buck each at a radio meet last weekend. The seller had
piles of them. I had my choice of Sylvania, RCA, GE, Tung Sol, etc. *Not
sure why you "don't like" GE's and RCA's. There's absolutely nothing wrong
with them. I wasn't even aware that Telefunken made these tubes. What is the
European number?

I think he meant 6U8 which is an ECF82 (I think).

[John Stone]

On 7/13/10 8:34 PM, in article
,
"Shhhh!!!! I'm Listening to Reason!" wrote:

I found most 6GH8s hummed in the ST-70 circuit I had which is my only
experience with them. That circuit was "phooey". I use Tele 6U8s in my
Scott, they do fine. I have about six more of them NOS.

I had a Dyna ST-70 that I dropped a new board into that used 6GH8s. I
never found one I liked. Amperex and all the other big names, bith US
and Euro, didn't work out very well.

Not sure why that would be, except that the 6GH8, like the 7199, was very
prone to heater to cathode leakage. I've used 6U8's in the Dyna circuits
with very good results. 6U8 and 6GH8 are very similar and can be directly
subbed for each other in some applications. The Sovtek 7199, which is now
discontinued, also had problems with hum in certain amps. You could fix it
by running the heaters on dc or superimposing a small amount of dc between
heater and ground.

[John Stone]

On 7/13/10 8:37 PM, in article
,
"Shhhh!!!! I'm Listening to Reason!" wrote:

I think he meant 6U8 which is an ECF82 (I think).

ECF802, I believe.

[Shhhh!!!! I'm Listening to Reason!]

On Jul 13, 8:56*pm, John Stone wrote:
On 7/13/10 8:34 PM, in article
,
"Shhhh!!!! I'm Listening to Reason!" wrote:

I found most 6GH8s hummed in the ST-70 circuit I had which is my only
experience with them. That circuit was "phooey". I use Tele 6U8s in my
Scott, they do fine. I have about six more of them NOS.

I had a Dyna ST-70 that I dropped a new board into that used 6GH8s. I
never found one I liked. Amperex and all the other big names, bith US
and Euro, didn't work out very well.

Not sure why that would be, except that the 6GH8, like the 7199, was very
prone to heater to cathode leakage. I've used 6U8's in the Dyna circuits
with very good results. 6U8 and 6GH8 are very similar and can be directly
subbed for each other in some applications. The Sovtek 7199, which is now
discontinued, also had problems with hum in certain amps. You could fix it
by running the heaters on dc or superimposing a small amount of dc between
heater and ground.

It was a relatively small sample of 6GH8, perhaps 8-10. I ended up
selling the Dyna amp and getting a solid-state shortly thereafter. Now
the only tubes I run are a Scott integrated for a secondary bedroom
system. I did recently pick up a Pilot 654 receiver but I haven't even
tested it yet.

[Clyde Slick]

On Jul 13, 9:25*pm, John Stone wrote:
On 7/13/10 7:54 PM, in article
, "Clyde

Slick" wrote:

6U8 and its cousin 6GH8, both of which were used extensively in tv
applications, are now being used to replace the difficult to find 7199 in
old Dynaco and other gear. Apparently the 7199 was little more than a 6GH8
with different basing and a spec for noise. There are plug in adapters
available or you can just rewire the socket. The subs yield equal or better
specs compared with the original tubes.

except that a good 6U8 is pretty hard to find, not as scarce as 7199,
but hard to find
a telefunken. Don't much like the GE'S and RCA's nor the 6GH8, except
for Sylvania's
these tubes *are used in my Scott integrateds,

The 7199's were all made by RCA regardless of the labeling. 6U8's and 6GH8's
are still as common as dirt. I bought a pair of NOS 6678 GE (industrial
version of 6U8) for a buck each at a radio meet last weekend. The seller had
piles of them. I had my choice of Sylvania, RCA, GE, Tung Sol, etc. *Not
sure why you "don't like" GE's and RCA's. There's absolutely nothing wrong
with them. I wasn't even aware that Telefunken made these tubes. What is the
European number?

telefunkens are labeled 6U8

[Clyde Slick]

On Jul 13, 11:47*pm, "Shhhh!!!! I'm Listening to Reason!"
wrote:
On Jul 13, 8:56*pm, John Stone wrote:



On 7/13/10 8:34 PM, in article
,
"Shhhh!!!! I'm Listening to Reason!" wrote:

I found most 6GH8s hummed in the ST-70 circuit I had which is my only
experience with them. That circuit was "phooey". I use Tele 6U8s in my
Scott, they do fine. I have about six more of them NOS.

I had a Dyna ST-70 that I dropped a new board into that used 6GH8s. I
never found one I liked. Amperex and all the other big names, bith US
and Euro, didn't work out very well.

Not sure why that would be, except that the 6GH8, like the 7199, was very
prone to heater to cathode leakage. I've used 6U8's in the Dyna circuits
with very good results. 6U8 and 6GH8 are very similar and can be directly
subbed for each other in some applications. The Sovtek 7199, which is now
discontinued, also had problems with hum in certain amps. You could fix it
by running the heaters on dc or superimposing a small amount of dc between
heater and ground.

It was a relatively small sample of 6GH8, perhaps 8-10. I ended up
selling the Dyna amp and getting a solid-state shortly thereafter. Now
the only tubes I run are a Scott integrated for a secondary bedroom
system. I did recently pick up a Pilot 654 receiver but I haven't even
tested it yet.

I run a Scott 299D in my bedroom system,'I think you said you run a
222c
a great amp,,my father had one, it brought me hours
of enjoyment constantly spinning the Beach Boys and Four tops

[Clyde Slick]

On Jul 13, 9:34*pm, "Shhhh!!!! I'm Listening to Reason!"
wrote:
On Jul 13, 7:54*pm, Clyde Slick wrote:



On Jul 13, 8:29*pm, John Stone wrote:

On 7/13/10 6:11 PM, in article
,
"Shhhh!!!! I'm Listening to Reason!" wrote:

6U8 (Scott used these a
lot), 6GC7/6FQ7, 12A*7 and the like are "phooey".

6U8 and its cousin 6GH8, both of which were used extensively in tv
applications, are now being used to replace the difficult to find 7199 in
old Dynaco and other gear. Apparently the 7199 was little more than a 6GH8
with different basing and a spec for noise. There are plug in adapters
available or you can just rewire the socket. The subs yield equal or better
specs compared with the original tubes.

except that a good 6U8 is pretty hard to find, not as scarce as 7199,
but hard to find
a telefunken. Don't much like the GE'S and RCA's nor the 6GH8, except
for Sylvania's
these tubes *are used in my Scott integrateds,

I found most 6GH8s hummed in the ST-70 circuit I had which is my only
experience with them. That circuit was "phooey". I use Tele 6U8s in my
Scott, they do fine. I have about six more of them NOS.

I had a Dyna ST-70 that I dropped a new board into that used 6GH8s. I
never found one I liked. Amperex and all the other big names, bith US
and Euro, didn't work out very well.

my various Scotts will use 6U8/6GH8,6BL8 and 6EA8

[Shhhh!!!! I'm Listening to Reason!]

On Jul 13, 11:19*pm, Clyde Slick wrote:
On Jul 13, 11:47*pm, "Shhhh!!!! I'm Listening to Reason!"





wrote:
On Jul 13, 8:56*pm, John Stone wrote:

On 7/13/10 8:34 PM, in article
,
"Shhhh!!!! I'm Listening to Reason!" wrote:

I found most 6GH8s hummed in the ST-70 circuit I had which is my only
experience with them. That circuit was "phooey". I use Tele 6U8s in my
Scott, they do fine. I have about six more of them NOS.

I had a Dyna ST-70 that I dropped a new board into that used 6GH8s. I
never found one I liked. Amperex and all the other big names, bith US
and Euro, didn't work out very well.

Not sure why that would be, except that the 6GH8, like the 7199, was very
prone to heater to cathode leakage. I've used 6U8's in the Dyna circuits
with very good results. 6U8 and 6GH8 are very similar and can be directly
subbed for each other in some applications. The Sovtek 7199, which is now
discontinued, also had problems with hum in certain amps. You could fix it
by running the heaters on dc or superimposing a small amount of dc between
heater and ground.

It was a relatively small sample of 6GH8, perhaps 8-10. I ended up
selling the Dyna amp and getting a solid-state shortly thereafter. Now
the only tubes I run are a Scott integrated for a secondary bedroom
system. I did recently pick up a Pilot 654 receiver but I haven't even
tested it yet.

I run a Scott 299D in my bedroom system,'I think you said you run a
222c
a great amp,,my father had one, it brought me hours
of enjoyment constantly spinning the Beach Boys and Four tops-

That's a 7591 amp? I don't remember.

[John Stone]

On 7/14/10 2:19 AM, in article
,
"Shhhh!!!! I'm Listening to Reason!" wrote:

I run a Scott 299D in my bedroom system,'I think you said you run a
222c
a great amp,,my father had one, it brought me hours
of enjoyment constantly spinning the Beach Boys and Four tops-

That's a 7591 amp? I don't remember.

I had a 299B, bought used when I was in college. I really liked that amp.
Used EL84's for outputs.

[Clyde Slick]

On Jul 14, 3:19*am, "Shhhh!!!! I'm Listening to Reason!"
wrote:
On Jul 13, 11:19*pm, Clyde Slick wrote:



On Jul 13, 11:47*pm, "Shhhh!!!! I'm Listening to Reason!"

wrote:
On Jul 13, 8:56*pm, John Stone wrote:

On 7/13/10 8:34 PM, in article
,
"Shhhh!!!! I'm Listening to Reason!" wrote:

I found most 6GH8s hummed in the ST-70 circuit I had which is my only
experience with them. That circuit was "phooey". I use Tele 6U8s in my
Scott, they do fine. I have about six more of them NOS.

I had a Dyna ST-70 that I dropped a new board into that used 6GH8s. I
never found one I liked. Amperex and all the other big names, bith US
and Euro, didn't work out very well.

Not sure why that would be, except that the 6GH8, like the 7199, was very
prone to heater to cathode leakage. I've used 6U8's in the Dyna circuits
with very good results. 6U8 and 6GH8 are very similar and can be directly
subbed for each other in some applications. The Sovtek 7199, which is now
discontinued, also had problems with hum in certain amps. You could fix it
by running the heaters on dc or superimposing a small amount of dc between
heater and ground.

It was a relatively small sample of 6GH8, perhaps 8-10. I ended up
selling the Dyna amp and getting a solid-state shortly thereafter. Now
the only tubes I run are a Scott integrated for a secondary bedroom
system. I did recently pick up a Pilot 654 receiver but I haven't even
tested it yet.

I run a Scott 299D in my bedroom system,'I think you said you run a
222c
a great amp,,my father had one, it brought me hours
of enjoyment constantly spinning the Beach Boys and Four tops-

That's a 7591 amp? I don't remember.

yes

[Clyde Slick]

On Jul 14, 6:22*am, John Stone wrote:
On 7/14/10 2:19 AM, in article
,
"Shhhh!!!! I'm Listening to Reason!" wrote:

I run a Scott 299D in my bedroom system,'I think you said you run a
222c
a great amp,,my father had one, it brought me hours
of enjoyment constantly spinning the Beach Boys and Four tops-

That's a 7591 amp? I don't remember.

I had a 299B, bought used when I was in college. I really liked that amp.
Used EL84's for outputs.

299 and 299b were EL84
299c and 299d were 7591
233 was also 7591
the kit LK72 and LK72b were also 7591

[Shhhh!!!! I'm Listening to Reason!]

On Jul 14, 7:15*am, Clyde Slick wrote:
On Jul 14, 3:19*am, "Shhhh!!!! I'm Listening to Reason!"

That's a 7591 amp? I don't remember.

yes

Have you used any of the recent reissues? I picked up a Pilot receiver
that uses 7591. They're still good but I always like to have a spare
set and I'd rather not pay $100+ for a quad.

[Boon[_2_]]

On Jul 14, 1:26*pm, "Shhhh!!!! I'm Listening to Reason!"
wrote:
On Jul 14, 7:15*am, Clyde Slick wrote:

On Jul 14, 3:19*am, "Shhhh!!!! I'm Listening to Reason!"
That's a 7591 amp? I don't remember.

yes

Have you used any of the recent reissues? I picked up a Pilot receiver
that uses 7591. They're still good but I always like to have a spare
set and I'd rather not pay $100+ for a quad.

Back when I had my 299C, there was a guy in Lithuania who was selling
a huge number of them on eBay. I was told by a fellow Scott owner that
this guy stumbled onto a warehouse full of them and bought them all,
and that he would have enough stock for decades of Scott owners. I
wish I could remember his name, but check out 7591s on eBay and see if
he's still around.

[Boon[_2_]]

On Jul 14, 3:47*pm, Boon wrote:
On Jul 14, 1:26*pm, "Shhhh!!!! I'm Listening to Reason!"

wrote:
On Jul 14, 7:15*am, Clyde Slick wrote:

On Jul 14, 3:19*am, "Shhhh!!!! I'm Listening to Reason!"
That's a 7591 amp? I don't remember.

yes

Have you used any of the recent reissues? I picked up a Pilot receiver
that uses 7591. They're still good but I always like to have a spare
set and I'd rather not pay $100+ for a quad.

Back when I had my 299C, there was a guy in Lithuania who was selling
a huge number of them on eBay. I was told by a fellow Scott owner that
this guy stumbled onto a warehouse full of them and bought them all,
and that he would have enough stock for decades of Scott owners. I
wish I could remember his name, but check out 7591s on eBay and see if
he's still around.

He was selling them for $14 each, if I remember correctly.

[Shhhh!!!! I'm Listening to Reason!]

On Jul 14, 3:48*pm, Boon wrote:
On Jul 14, 3:47*pm, Boon wrote:





On Jul 14, 1:26*pm, "Shhhh!!!! I'm Listening to Reason!"

wrote:
On Jul 14, 7:15*am, Clyde Slick wrote:

On Jul 14, 3:19*am, "Shhhh!!!! I'm Listening to Reason!"
That's a 7591 amp? I don't remember.

yes

Have you used any of the recent reissues? I picked up a Pilot receiver
that uses 7591. They're still good but I always like to have a spare
set and I'd rather not pay $100+ for a quad.

Back when I had my 299C, there was a guy in Lithuania who was selling
a huge number of them on eBay. I was told by a fellow Scott owner that
this guy stumbled onto a warehouse full of them and bought them all,
and that he would have enough stock for decades of Scott owners. I
wish I could remember his name, but check out 7591s on eBay and see if
he's still around.

He was selling them for $14 each, if I remember correctly.

I think those days are long gone but I'll look.Electro Harmonix and
the other reissues are about $80/quad. I think an NOS quad of
Sylvanias (who was the only manufacturer AFAIK) are $130+.

[Bret L]

*I mean, penishead, that a small signal tube is optimized for audio in
a different way than a power output tube. For example the heater
connections may be changed to reduce hum, important in preamps and
power amp first stages, irrelevant in a power tube.

Therefore the 7025 is the only 12AX7 variant designed with audio in
mind. Any company that uses a standard 12AX7 is "phooey".

Most all 12AX7s were dual numbered from the late LBJ era on.



i.e, whether one is talking about small signal or power tubes, and as
opposed to general purpose tubes or tubes specifically designed for
other purposes. In some cases tubes specifically designed for other
applications work quite well in audio applications and in others not
so well.

That makes no difference, people.

*In the case of power tubes, specifically audio types differ from RF
output, TV horizontal deflection, and voltage regulator tubes in
several areas. Linearity is at a premium, plate caps are undesireable,

Tell that to McIntosh, who used 6BG6 tubes with great success. Yes,
it's similar to 6L6 tubes. However, they used these tubes even though
6L6 tubes were as cheap and (perhaps) more plentiful.

*Only on one, obscure industrial model

Did I say otherwise?

http://mcc.berners.ch/power-amplifiers/A116.pdf

*This tube was identical to the 6L6 except for pin out...http://www.vacuumtubes.com/6BG6.html

So why did they use a horizontal deflection tube? McIntosh is clearly
"phooey".

The same reason legions of CB linear builders did and even still do.
In a Class B device operating at a high crest factor it was the
cheapest and most easily field obtainable way to get a certain level
of plate dissipation, without going to transmitting tubes and their
higher plate load (and transformer winding ratio) requirements. This
was a Nestorovic/Modafferi design and they were damn good. Julius
Futterman (don't even say it) was also good though a bit obsessed and
his OTL tube designs worked well-if you understood their very
significant limitations.

But all things being equal, these designs would have benefitted from
more linear tubes.

McIntosh approached Varian EIMAC for a purpose built audio tube and
Eimac wanted nowt to do with audio.

If I had a timeride offer I'd ask Frank McIntosh why he never thought
of the EL156, but since John Titor has not shown back up I guess we
will never know. as Frank and Gordon Gow are both very dead.

[Shhhh!!!! I'm Listening to Reason!]

On Jul 14, 6:52*pm, Bret L wrote:
*I mean, penishead, that a small signal tube is optimized for audio in
a different way than a power output tube. For example the heater
connections may be changed to reduce hum, important in preamps and
power amp first stages, irrelevant in a power tube.

Therefore the 7025 is the only 12AX7 variant designed with audio in
mind. Any company that uses a standard 12AX7 is "phooey".

Most all 12AX7s were dual numbered from the late LBJ era on.

So what? As tube production wound down many tubes were relabelled with
multiple numbers.

Were they audio tubes to begin with? I think not. They were "phooey".

i.e, whether one is talking about small signal or power tubes, and as
opposed to general purpose tubes or tubes specifically designed for
other purposes. In some cases tubes specifically designed for other
applications work quite well in audio applications and in others not
so well.

That makes no difference, people.

*In the case of power tubes, specifically audio types differ from RF
output, TV horizontal deflection, and voltage regulator tubes in
several areas. Linearity is at a premium, plate caps are undesireable,

Tell that to McIntosh, who used 6BG6 tubes with great success. Yes,
it's similar to 6L6 tubes. However, they used these tubes even though
6L6 tubes were as cheap and (perhaps) more plentiful.

*Only on one, obscure industrial model

Did I say otherwise?

http://mcc.berners.ch/power-amplifiers/A116.pdf

*This tube was identical to the 6L6 except for pin out...http://www..vacuumtubes.com/6BG6.html

So why did they use a horizontal deflection tube? McIntosh is clearly
"phooey".

*The same reason legions of CB linear builders did and even still do.
In a Class B device operating at a high crest factor it was the
cheapest and most easily field obtainable way to get a certain level
of plate dissipation, without going to transmitting tubes and their
higher plate load (and transformer winding ratio) requirements. This
was a Nestorovic/Modafferi design and they were damn good. Julius
Futterman (don't even say it) was also good though a bit obsessed and
his OTL tube designs worked well-if you understood their very
significant limitations.

*But all things being equal, these designs would have benefitted from
more linear tubes.

As I said, 6L6s were cheap and plentiful. You're emitting large
amounts of gas out of your rear end, Bratzi.

*McIntosh approached Varian EIMAC for a purpose built audio tube and
Eimac wanted nowt to do with audio.

*If I had a timeride offer I'd ask Frank McIntosh why he never thought
of the EL156, but since John Titor has not shown back up I guess we
will never know. as Frank and Gordon Gow are both very dead.

And both very "phooey".

[Clyde Slick]

On Jul 14, 2:26*pm, "Shhhh!!!! I'm Listening to Reason!"
wrote:
On Jul 14, 7:15*am, Clyde Slick wrote:

On Jul 14, 3:19*am, "Shhhh!!!! I'm Listening to Reason!"
That's a 7591 amp? I don't remember.

yes

Have you used any of the recent reissues? I picked up a Pilot receiver
that uses 7591. They're still good but I always like to have a spare
set and I'd rather not pay $100+ for a quad.

Electro Harmonex, in my 299D, sounds great, a little taller and fatter
tube, can't put the thing in its
case, which is no big deal to me because, to me, they sound better
when out of' the case.
See, they are too large to use in Fishers, which space the tubes
closer together.
Not being familiar wiht the Pilot, I can't advise.

[Shhhh!!!! I'm Listening to Reason!]

On Jul 15, 12:52*am, Clyde Slick wrote:
On Jul 14, 2:26*pm, "Shhhh!!!! I'm Listening to Reason!"

wrote:
On Jul 14, 7:15*am, Clyde Slick wrote:

On Jul 14, 3:19*am, "Shhhh!!!! I'm Listening to Reason!"
That's a 7591 amp? I don't remember.

yes

Have you used any of the recent reissues? I picked up a Pilot receiver
that uses 7591. They're still good but I always like to have a spare
set and I'd rather not pay $100+ for a quad.

Electro Harmonex, in my 299D, sounds great, a little taller and fatter
tube, can't put the thing in its
case, which is no big deal to me because, to me, they sound better
when out of' the case.
See, they are too large to use in Fishers, which space the tubes
closer together.
Not being familiar wiht the Pilot, I can't advise.

I think there would be space as far as socket spacing. This one was
out of a console so there wasn't a case with it so the height doesn't
matter. I'll check them out.

Does your Scott honk at 30 Hz?

[Clyde Slick]

On Jul 15, 2:12*am, "Shhhh!!!! I'm Listening to Reason!"
wrote:
On Jul 15, 12:52*am, Clyde Slick wrote:



On Jul 14, 2:26*pm, "Shhhh!!!! I'm Listening to Reason!"

wrote:
On Jul 14, 7:15*am, Clyde Slick wrote:

On Jul 14, 3:19*am, "Shhhh!!!! I'm Listening to Reason!"
That's a 7591 amp? I don't remember.

yes

Have you used any of the recent reissues? I picked up a Pilot receiver
that uses 7591. They're still good but I always like to have a spare
set and I'd rather not pay $100+ for a quad.

Electro Harmonex, in my 299D, sounds great, a little taller and fatter
tube, can't put the thing in its
case, which is no big deal to me because, to me, they sound better
when out of' the case.
See, they are too large to use in Fishers, which space the tubes
closer together.
Not being familiar wiht the Pilot, I can't advise.

I think there would be space as far as socket spacing. This one was
out of a console so there wasn't a case with it so the height doesn't
matter. I'll check them out.

Does your Scott honk at 30 Hz?7

kind of of fat under 40, but not one note bass nor an overpowering
resonance, the 7591 amps tend to be more fat on the bottom than the
6BQ5 amps. this also gives the 6Bq5 ampsw an increased aura of
imaging. there are people who like the 6bQ5 sCOTTS OVER THE 7591
Scotts.
Pierre Sprey (of Mapleshade cd;s) used to do mods to the 6BQ5 Scott
amps, but wouldn't bother with the 7591 Scott amps

[Shhhh!!!! I'm Listening to Reason!]

On Jul 15, 1:44*am, Clyde Slick wrote:
On Jul 15, 2:12*am, "Shhhh!!!! I'm Listening to Reason!"





wrote:
On Jul 15, 12:52*am, Clyde Slick wrote:

On Jul 14, 2:26*pm, "Shhhh!!!! I'm Listening to Reason!"

wrote:
On Jul 14, 7:15*am, Clyde Slick wrote:

On Jul 14, 3:19*am, "Shhhh!!!! I'm Listening to Reason!"
That's a 7591 amp? I don't remember.

yes

Have you used any of the recent reissues? I picked up a Pilot receiver
that uses 7591. They're still good but I always like to have a spare
set and I'd rather not pay $100+ for a quad.

Electro Harmonex, in my 299D, sounds great, a little taller and fatter
tube, can't put the thing in its
case, which is no big deal to me because, to me, they sound better
when out of' the case.
See, they are too large to use in Fishers, which space the tubes
closer together.
Not being familiar wiht the Pilot, I can't advise.

I think there would be space as far as socket spacing. This one was
out of a console so there wasn't a case with it so the height doesn't
matter. I'll check them out.

Does your Scott honk at 30 Hz?7

kind of of fat under 40, but not one note bass nor an overpowering
resonance, the 7591 amps tend to be more fat on the bottom than the
6BQ5 amps. this also gives the 6Bq5 ampsw an increased aura of
imaging. there are people who like the 6bQ5 sCOTTS OVER THE 7591
Scotts.
Pierre Sprey (of Mapleshade cd;s) *used to do mods to the 6BQ5 Scott
amps, but wouldn't bother with the 7591 Scott amps

I use Reflektor military 6p14p-ER in my Scott. They're a well-built,
good-sounding tube. They claim 10,000 hours life. I noticed a
significant improvement in bass with them over the Mullards and
Brimars I'd been using. The highs are crisp and the midrange, while
not as sweet as the Mullards, is quite acceptable.

The Russian tubes have come a long, long way.