[Mechans1]

I have found some plain jane 6AS7G coke bottle tubes that are quiet.  The 5998 types I own have mostly been a little noisy to ridiculous burned out pieces of junk with all sorts of issues.  The Western Electric 421A  have issues, again from over use and people passing garbage tubes to one another.  When reasonably quiet, the sonics are very pretty and they produce 3 dimensional, spatial  sound stages.  They do sound better than the 6080 with qualities described previously in this thread.
A Farady cage captures the EMI  and other interfering signals.  Some people live in areas that have a lot of that stuff  in their environment.  A copper cage is very effective.
My problem is that my amp has decided to play one channel at a time and the company that made it is defunct.  If anyone knows where to get a SinglePower amp fixed ,please let me know. 

 

[mcandmar]

Here is an interesting tube for you collectors out there.   I have a few Gold Aero tubes in 6CG7 and 6DJ8 form and they all test with amazingly high emissions and perfectly matched sections. From what i was able to find out they cherry picked the best tubes they could find from a variety of manufacturers, then graded and branded them.  Granted they started life as lowly GE 5998A's but i could'nt resist picking one up to see how it performs..  http://www.ebay.co.uk/itm/172262170880

 

[leftside]

  I have found some plain jane 6AS7G coke bottle tubes that are quiet.  The 5998 types I own have mostly been a little noisy to ridiculous burned out pieces of junk with all sorts of issues.  The Western Electric 421A  have issues, again from over use and people passing garbage tubes to one another.  When reasonably quiet, the sonics are very pretty and they produce 3 dimensional, spatial  sound stages.  They do sound better than the 6080 with qualities described previously in this thread.
A Farady cage captures the EMI  and other interfering signals.  Some people live in areas that have a lot of that stuff  in their environment.  A copper cage is very effective.
My problem is that my amp has decided to play one channel at a time and the company that made it is defunct.  If anyone knows where to get a SinglePower amp fixed ,please let me know. 

You shouldn't need the manufacturer to fix your amp. Any decent audio technician should be able to do the job.

 

[oshipao]

Hej Oshipao,

I have tried numerous 6AS7G variants and 6080 variants. If you want something less expensive that sounds better than the RCA 6AS7G tubes, try the 6AS7GA (any brand).

BUT, the very inexpensive 6BL7 sounds better than most, if not all, 6AS7 type tubes. This tube draws 1.5A, versus 2.5A for the 6AS7. Combining the 6BL7 with a 6SN7 tube, using a dual adapter, draws 1.5A + 0.6A = 2.1A, which is compatible with any amp using 6AS7 power tubes.

This combination is outstanding in sound quality and well worth trying.

Hi hodgjy,

Have you tried a Faraday cage to eliminate tube noise? Basically, you can use an inexpensive wire mesh basket or similar, and place over the tubes.

Hej Mordy

Maybe I'll get to those tubes further down the road. I am trying to keep things simple at the moment without adapters. Went ahead and ordered a pair of Tung Sol 6AS7G and a pair of Ken Rad 6SN7GT. Let's see how these will fare to begin with.

 

[Mechans1]

Hej Mordy

Maybe I'll get to those tubes further down the road. I am trying to keep things simple at the moment without adapters. Went ahead and I ordered a pair of Tung Sol 6AS7G and a pair of Ken Rad 6SN7GT. Let's see how these will fare to begin with.

I share your philosophy/approach.  The old audiophile dictum is to keep parts and interfaces to a minimum -as well as  to keep signal paths short and simple.  If someone designs an amp around 6BL7 tubes I would very interested in hearing it.

 

[gibosi]

  I share your philosophy/approach.  The old audiophile dictum is to keep parts and interfaces to a minimum -as well as  to keep signal paths short and simple.  If someone designs an amp around 6BL7 tubes I would very interested in hearing it.

 
I suspect that there is just not enough stock of 6BL7 for a major manufacturer such as Woo to use these tubes. But a custom builder has much more freedom to use uncommon tubes. And, for example, Glenn has built a a number of amps designed to use the 6BL7. You might find this review interesting:
 
 http://www.tweak-fi.com/apps/blog/show/42754587-building-a-reference-system-part-2-glenn-s-headphone-amplifier

 

[lukeap69]

  I share your philosophy/approach.  The old audiophile dictum is to keep parts and interfaces to a minimum -as well as  to keep signal paths short and simple.  If someone designs an amp around 6BL7 tubes I would very interested in hearing it.

 
As @gibosi said Glenn had designed some OTL amps using six-6BL7's and I believe the latest is mine. It is a wonderful amp and the almost one year wait is well worth it. See my sig for the link of my amp.

 

[JazzVinyl]

As @gibosi
 said Glenn had designed some OTL amps using six-6BL7's and I believe the latest is mine. It is a wonderful amp and the almost one year wait is well worth it. See my sig for the link of my amp.

Indeed! A Glenn amp designed around 6x 6BL7's as powers!!!

Could it get any better?

 

[Mechans1]

Indeed! A Glenn amp designed around 6x 6BL7's as powers!!!

Could it get any better?

So how do I get to hear it? 
Can these 6  X  6BL7s drive a speaker as well, even without output transformers?

 

[gibosi]

  So how do I get to hear it? 
Can these 6  X  6BL7s drive a speaker as well, even without output transformers?

 
As Glenn is a custom builder, you cannot simply go to an audio shop and try one out. If you want to hear one, you would have to contact someone who has such an amp and make arrangements.
 
To the best of my knowledge, six 6BL7s cannot drive loudspeakers. The six 6BL7s simply take the place of two 6AS7s in a standard OTL.

 

[Mechans1]

   
As Glenn is a custom builder, you cannot simply go to an audio shop and try one out. If you want to hear one, you would have to contact someone who has such an amp and make arrangements.
 
To the best of my knowledge, six 6BL7s cannot drive loudspeakers. The six 6BL7s simply take the place of two 6AS7s in a standard OTL.

I had been told about  Glenn's amps all being custom some time back.  I was wondering if the tubes had been used in some other application.  I saw that Glenn  can use a variety of tubes to build an amp, 6 X 6SN7s  to equal the 6 X 6BL7s to equal 2 X  6AS7   etc..etc... but only after I asked that question.
.

 

[lukeap69]

I had been told about  Glenn's amps all being custom some time back.  I was wondering if the tubes had been used in some other application.  I saw that Glenn  can use a variety of tubes to build an amp, 6 X 6SN7s  to equal the 6 X 6BL7s to equal 2 X  6AS7   etc..etc... but only after I asked that question.
.

 


Not sure what you mean by ' I was wondering if the tubes had been used in some other application'.

Glenn will build your amp depending on your requirement. For example, I have asked him what would be best for my HD800, he recommended C3g for driver and 6BL7 for output. So I have 6 numbers of sockets for output tubes. In order for the amp to be flexible, the amp can also run 2 or 4 number of 6AS7's or 2 number of 6336 for low Z cans. In my experience so far, 4 number of Chatham 6AS7 had been best for my Oppo PM-2.

Other OTL amps, like @whirlwind 's, have the option to use C3g or 6SN7 driver tubes. Although he needs adapter to run quad 6BL7 (or 6BX7) tubes as power. Glenn can also supply some tubes he has if you prefer or just buy the amp from him and source your own tubes. He is that flexible. The only thing is, there are quite a few in the queue so it will take some time if you want to get one.

 

[Mechans1]

What I meant was where else are 6BL7s used?   They are NOS but there might have been some other audio  gear where the character of the tube has an obvious effect on the sound that equipment makes.
One rather indelicate question is how expensive are Glenn's amps?  I would guess it depends in part on what you ask for,  I am rather curious about a general price point or  range.
.I have a lot of tubes, far too many, but most were acquired for speaker amp systems.  The 6SN7 option has my attention albeit somewhat pedestrian compared with some of the other tubes mentioned. ( I would have guessed the 6SL7 as a potential power tube because it has higher gain than the SN7.)   I own a 6SN7 pre amp and an integrated that used them in addition to my headphone amp.  That got me started on rolling and I went semi crazy.
 It may sound like bragging, but in truth it is foolish, to have so many tubes.  I  did a quick count of just  my Sylvania Ws a favorite of mine, I have at least 33. They represent a small fraction of the total 6SN7s. I wonder if you could tailor your sound using a mix of 6SN7s?
I  have plenty of the noval mini dual triodes like 12AU7s etc.  I know Tim Paravincinni (sp?) built a speaker amp for  DCS using 20 X  12AX7s.

 

[gibosi]

 
What I meant was where else are 6BL7s used?   They are NOS but there might have been some other audio  gear where the character of the tube has an obvious effect on the sound that equipment makes.
One rather indelicate question is how expensive are Glenn's amps?  I would guess it depends in part on what you ask for,  I am rather curious about a general price point or  range.
.I have a lot of tubes, far too many, but most were acquired for speaker amp systems.  The 6SN7 option has my attention albeit somewhat pedestrian compared with some of the other tubes mentioned. ( I would have guessed the 6SL7 as a potential power tube because it has higher gain than the SN7.)   I own a 6SN7 pre amp and an integrated that used them in addition to my headphone amp.  That got me started on rolling and I went semi crazy.
 It may sound like bragging, but in truth it is foolish, to have so many tubes.  I  did a quick count of just  my Sylvania Ws a favorite of mine, I have at least 33. They represent a small fraction of the total 6SN7s. I wonder if you could tailor your sound using a mix of 6SN7s?
I  have plenty of the noval mini dual triodes like 12AU7s etc.  I know Tim Paravincinni (sp?) built a speaker amp for  DCS using 20 X  12AX7s.

 
6BL7s were developed for use in televisions, specifically to handle the power requirements of larger screens with higher resolutions. As they replaced 6SN7s in order to meet the requirements of larger screens you might consider the 6BL7 to be 6SN7 on steroids. But again, these tubes are not available in sufficient numbers to be used by Woo or any other large scale manufacturer. You will find them only in custom amps.
 
It is my understanding that when selecting power tubes for use in OTLs, it is not gain but current that matters. For example, a 6SL7 simply cannot move enough current to drive a pair of HD650s. The 6BL7 can move considerably current than a 6SN7, but not as much as a 6AS7. However, running multiple pairs of 6BL7s compares very favorably with the 6AS7.
 
If you want to know more about Glenn's amps, I suggest you contact him directly. His handle here is 2359glenn. I don't know for sure, but I believe you can get a basic 6AS7/6SN7/5U4G OTL for around $700. And the price goes up from there, with 300B/C3g with output transformers going for around $4,000, I think. But again, don't quote me on these prices. These are just guesses on my part...

 

[attmci]

  Hej Oshipao,
 
I have tried numerous 6AS7G variants and 6080 variants. If you want something less expensive that sounds better than the RCA 6AS7G tubes, try the 6AS7GA (any brand).
 
BUT, the very inexpensive 6BL7 sounds better than most, if not all, 6AS7 type tubes. This tube draws 1.5A, versus 2.5A for the 6AS7. Combining the 6BL7 with a 6SN7 tube, using a dual adapter, draws 1.5A + 0.6A = 2.1A, which is compatible with any amp using 6AS7 power tubes.
 
This combination is outstanding in sound quality and well worth trying.
 
Hi hodgjy,
 
Have you tried a Faraday cage to eliminate tube noise? Basically, you can use an inexpensive wire mesh basket or similar, and place over the tubes.