[Silent One]

Update on National Union! 
 
The Russians are coming... the Russians are coming... again... the Russians... to the rescue? It's a wrap!!! Replaced the 5998's with the Russian 6AS7G's as promised tonight. And silence. Dead silence. Volume up, volume down, music playing, music paused all without incident. 
 
Initially, I was going to replace the '596' too, but I like it too much. 

 No matter, the National Union is fine - no issues of hum, no issues of microphonics. With the former, it could be heard even when music is not playing when the 5998's are installed; very micro-phonic around face-plate and especially the volume control knob. With the Russians, no worries.
 
So, how does it sound SO? It sounds promising and I like it. The TS-BGRP brings more to the table but the NU is quite serviceable. On the flip side, the 5998's bring more to the table (mine anyway) than the Russians but we're seeing obvious trade offs. More detail & noise versus less detail but silence. Maybe Sunday night, if I return home before midnight, will see the Sylvania's slide in there for a brief comparison.
 
Randomly selected tracks in alpha order A-C:
 
Abraham Laboriel -  Holidays 
 
Al Jarreau - Golden Girl
 
Angela Bofill - I Try
 
Astrud Gilberto - Non-Stop To Brazil
                           - Fly Me To The Moon
                           - The Shadow Of Your Smile
 
B.B. King - Ask Me No Questions
                  - To Know You Is To Love You
 
Beatles, The - Back In The U.S.S.R.
 
Busi Mhlongo - Izinziswa
 
Candi Staton - Victim
 
Cars, The - Candy-O

 

[Silent One]

Quote:

Well, it's a shame that the tube is no good, but all the same I'm thankful it isn't my amp.  Thanks for reporting your findings SO.
 
Rosgr, I'm still concerned this might have been my fault during my cleaning process.  I try to be gentle, but polishing the pins with steel wool requires working the piece back and forth across the pins so the shaking action might have shifted the mica tabs holding the plate against the glass, or dislodged some sort of material.  Of course it could also have happened in shipping, where it would have been jostled around a lot.  I've cleaned a lot of tubes this way and had no problems until my TSRP so I'm giving myself the benefit of the doubt for now. 

 
You did an excellent job cleaning the pins! The NU is fine after all...

 

[rosgr63]

Quote:

Well, it's a shame that the tube is no good, but all the same I'm thankful it isn't my amp.  Thanks for reporting your findings SO.
 
Rosgr, I'm still concerned this might have been my fault during my cleaning process.  I try to be gentle, but polishing the pins with steel wool requires working the piece back and forth across the pins so the shaking action might have shifted the mica tabs holding the plate against the glass, or dislodged some sort of material.  Of course it could also have happened in shipping, where it would have been jostled around a lot.  I've cleaned a lot of tubes this way and had no problems until my TSRP so I'm giving myself the benefit of the doubt for now. 

xcalibur no way pin cleaning could have caused this.
I too use a nail file or steel wool but never had any problems.
If anything pin cleaning is an essential care of a tube.
 
Waiting for SO's further testing.
It's good news indeed that both amps exhibit the same behavior using the same tube.

 

[rosgr63]

Revelation time:
 
It's the ECC40.
 
Currently amp testing a Tungsram, doesn't sound too bad.

 

[hodgjy]

Are those the Svetlanas (6H13C)? Those are underrated and under appreciated tubes. They have a slight veil to them, but they have a pleasing warmth. Most importantly, they are dead silent.

Update on National Union! 

The Russians are coming... the Russians are coming... again... the Russians... to the rescue? It's a wrap!!! Replaced the 5998's with the Russian 6AS7G's as promised tonight. And silence. Dead silence. Volume up, volume down, music playing, music paused all without incident. 

 

[Xcalibur255]

Quote:

Update on National Union! 
 
The Russians are coming... the Russians are coming... again... the Russians... to the rescue? It's a wrap!!! Replaced the 5998's with the Russian 6AS7G's as promised tonight. And silence. Dead silence. Volume up, volume down, music playing, music paused all without incident. 
 
Initially, I was going to replace the '596' too, but I like it too much. 

 No matter, the National Union is fine - no issues of hum, no issues of micro-phonics. With the former, it could be heard even when music is not playing when the 5998's are installed; very micro-phonic around face-plate and especially the volume control knob. With the Russians, no worries.
 
So, how does it sound SO? It sounds promising and I like it. The TS-BGRP brings more to the table but the NU is quite serviceable. On the flip side, the 5998's bring more to the table (mine anyway) than the Russians but we're seeing obvious trade offs. More detail & noise versus less detail but silence. Maybe Sunday night, if I return home before midnight, will see the Sylvania's slide in there for a brief comparison.

So we have two possibilities: a) the noise is still there and the greatly decreased mu factor of the 6AS7 is simply hiding it, or b) the 5998s load the 6SN7 differently from an electrical standpoint and it is revealing the issue due to operational stress which is not present when paired with a 6AS7.
 
I too thought the NU was not bad with the Sylvania 6AS7s I tried it with, the tonal balance of each tube seemed to complement each other well.  The 5998, even setting the noise issue aside, doesn't pair well with the NU and sounds unbalanced in the mids and lower treble.  I would not take it over my trusty Sylvania though, and I can think of a couple of other tubes that pair better with 6AS7s too such as the Hitachi. 

 

[Xcalibur255]

Quote:

Revelation time:
 
It's the ECC40.
 
Currently amp testing a Tungsram, doesn't sound too bad.

Looking forward to reading upcoming impressions on this. 

 

[Silent One]

Quote:

Quote:

Update on National Union! 
 
The Russians are coming... the Russians are coming... again... the Russians... to the rescue? It's a wrap!!! Replaced the 5998's with the Russian 6AS7G's as promised tonight. And silence. Dead silence. Volume up, volume down, music playing, music paused all without incident. 
 
Initially, I was going to replace the '596' too, but I like it too much. 

 No matter, the National Union is fine - no issues of hum, no issues of microphonics. With the former, it could be heard even when music is not playing when the 5998's are installed; very micro-phonic around face-plate and especially the volume control knob. With the Russians, no worries.
 
So, how does it sound SO? It sounds promising and I like it. The TS-BGRP brings more to the table but the NU is quite serviceable. On the flip side, the 5998's bring more to the table (mine anyway) than the Russians but we're seeing obvious trade offs. More detail & noise versus less detail but silence. Maybe Sunday night, if I return home before midnight, will see the Sylvania's slide in there for a brief comparison.

So we have two possibilities: a) the noise is still there and the greatly decreased mu factor of the 6AS7 is simply hiding it, or b) the 5998s load the 6SN7 differently from an electrical standpoint and it is revealing the issue due to operational stress which is not present when paired with a 6AS7.
 
I too thought the NU was not bad with the Sylvania 6AS7s I tried it with, the tonal balance of each tube seemed to complement each other well.  The 5998, even setting the noise issue aside, doesn't pair well with the NU and sounds unbalanced in the mids and lower treble.  I would not take it over my trusty Sylvania though, and I can think of a couple of other tubes that pair better with 6AS7s too such as the Hitachi. 

 
 
I'm glad you read my post and sent the following contribution. It is something that mirrors my thoughts and may not have been fully expressed. But recognized through your own expression. What grade steel wool are you using? Should post a sample, a quick pix if you would. I was diggin' the clean pins! 

 

[Silent One]

Quote:

Are those the Svetlanas (6H13C)? Those are underrated and under appreciated tubes. They have a slight veil to them, but they have a pleasing warmth. Most importantly, they are dead silent.
Quote:

Update on National Union! 

The Russians are coming... the Russians are coming... again... the Russians... to the rescue? It's a wrap!!! Replaced the 5998's with the Russian 6AS7G's as promised tonight. And silence. Dead silence. Volume up, volume down, music playing, music paused all without incident. 

 
Yes, Svetlanas 6H13C's 

 hiding in the West. And yes sir, they are dead silent! That to me is impressive in its own right. Demonstrated by my turn of the dial toward maximum with no music playing.

 

[Silent One]

Quote:

Revelation time:
 
It's the ECC40.
 
Currently amp testing a Tungsram, doesn't sound too bad.

 
Great! However, in what way do you mean? In Paris, when something is excellent and perhaps sublime, Parisiens will say "Not bad." Are you understating or it actually doesn't sound too bad? 

 

[Silent One]

Just heard from our amp designer. Hopes to get released Tuesday... for good!

 

[john57]

Glenn likes the Svetlanas 6H13C's since they can handle higher voltages and hold up a bit better than some of the other 6AS7/6080 tubes 

 

[Silent One]

If they offered more detail at their prices, they'd be a killa! 

 

[Xcalibur255]

Quote:

 
 
I'm glad you read my post and sent the following contribution. It is something that mirrors my thoughts and may not have been fully expressed. But recognized through your own expression. What grade steel wool are you using? Should post a sample, a quick pix if you would. I was diggin' the clean pins! 

Grade #0000 - Final Finish/Super Fine
 
It takes more work on pins that are rough but it takes all the friction out of insertion and removal.  I always follow it with deoxit and then a final alcohol cleaning to prevent deoxit from building up on socket parts.

 

[Xcalibur255]

Quote:

Just heard from our amp designer. Hopes to get released Tuesday... for good!

Very happen news, this is.