[Yomaha]

I wasn't sure where to put this, but since it has tubes I thought this made sense.  If not, pls move to a better circle. 

I've seen nothing but rave reviews for this amplifier.  Granted, I don't see too many reviews that aren't positive, but this amp gets a lot of love.  Has anyone of this forum used it?  If so any experience rolling tubes thru it.  I've read that the stock 6922 Genalex are OK, but that it is very responsive to other tubes such as the Amperex 7308's.  Tunsgram 7dj8's are supposed to be pretty good in there are well.   

[Photon46]

I've been using a BHK250 with a BHK preamp for almost a year now. Both are quite revealing of any tube changes. As to what tubes are going to float your boat, that's going to depend on the rest of your system and power conditioning. PS Audio's website has an owner's forum with much discussion about this topic.

In my case, the addition of a High Fidelity Cables MC-0.5 power conditioner on the outlet feeding the BHK250 opened up more tube possibilities that sound appealing. The advertised attributes of the MC-0.5 are exactly what was delivered. Prior to that addition, my favorite tubes were either Raytheon 7308's or Voshkod 6n23p's from the early 70's. The MC-0.5 allowed me to use tubes that previously presented too much sibilance. I'm running Phillips SQ 6922's right now that sound excellent. At this time, I can't imagine wanting to swap out either BHK component for anything else as they perform at a very high level for their price. Plus, PS Audio's customer service is stellar (should service ever be an issue.)

[Yomaha]

Thx Photon.  I have a 250 on the way...should be here in a couple of weeks.  I spent most all of yesterday reading the PS owners forums on tubes in the 250's.  It was a long thread and I may have overlooked it, but I do not recall seeing the Raytheon 7308's or Voshkod 6n23p's mentioned.  So great to know those are working nicely for you!  For my amplifiers, I have gone from tube to Solid State and now to hybrid...the temptation of tube rolling was too much for me to bear.

[Photon46]

Hope you enjoy it as much as I have. Just remember to take all "authoritative" advice about tubes with a liberal grain of salt. For everyone that loves tube "A" in the amp there's an equal number with an opposite opinion it seems. 

[Yomaha]

I just got some NOS Amperex 7308’s to put in a BHK250 that is headed my way. These are a sub for 6922’s. I’ve read a lot of good things about this tube. I will let my ears be the judge. Anyone here have any experience with these?

[Yomaha]

Oh jeez...sorry...I should have put this under my existing thread. It’s late..and I’m posting from my iPhone 

[Tom Bombadil]

I've been running them in two preamps and an amplifier for many years.  Big thumps up.   They may not be the ultimate in high frequency detail but they produce a very pleasant, natural sound with a big soundstage.   I was lucky to pick up 3 pair about 15 years ago and have never gone back to any other 6922/7308 since.   Prices were much better on them 15 years ago.

[Yomaha]

I've been running them in two preamps and an amplifier for many years.  Big thumps up.   They may not be the ultimate in high frequency detail but they produce a very pleasant, natural sound with a big soundstage.   I was lucky to pick up 3 pair about 15 years ago and have never gone back to any other 6922/7308 since.   Prices were much better on them 15 years ago.

LOL yah I bet prices were waaaaay better 15 years ago 

These weren't cheap, but not absurd.  I got them thru Upscale, which I know is usually the most expensive, but I haven't had any bad tubes from them, so I feel like I'm paying up to ensure that I get a good tube.  My amp was supposed to be here today, but it got stuck on severe weather up north, so I will have to find something else to do this weekend...

[Tom Bombadil]

A guy I know told me a sad story about these tubes.  They used to use Amperex JAN 6922 and 7308 in military equipment.   He heard about the military liquidating some large tube stockpiles in the 1990s.  His buddy needed 6DJ8 equivalents and loaded up a bag full of them.  They were heading out and passed some 55 gallon drums filled full of tubes, heading for the landfill.  Two of them were filled with these Amperex and they were told to take whatever they wanted, all new still in their boxes.  My friend put a dozen or so in his pockets just in case he might need them someday. 

Who knows how many of these wonderful tubes went to that landfill?   Many hundreds.   Or how many worldwide met this fate. 

This is basically how I got mine too.  A different guy went to a different base and bought up a large stock of many tubes.   Including a lot of these 6922 and 7308.  Then he sold them for $8 each.  I bought 12 from him. 

And this is why they sell for $100+ today. 

[Yomaha]

That's a wild story Tom!  I think I'd be visibly upset if I saw all those tubes being flung into a landfill.

I've got the BHK in my system now...and...wow!  It's definitely a new level of audio experience for me.  You can hear the venue and space the music was performed in,
 with great separation and detail.  It's very clear and very musical.  It brought out the low end in my Salk Songtower RT's that I didn't even know was there.  I haven't even hooked my REL T9i back up, bc its added that much bass.  And bass in a good tight, round but punchy kind of way.  I've found myself singing along out loud alot more than usual, and way more air guitar...even some air drumming (which is frowned upon in my household

I realize that everyone is at different stages in their audio journey, so a BHK250 is small potatoes to some, but it's an oversized loaded baked potatoe for me.  We are really enjoying this amp!  I can't way to roll more tubes thru it. 

[who?me?]

I just got some NOS Amperex 7308’s to put in a BHK250 that is headed my way. These are a sub for 6922’s. I’ve read a lot of good things about this tube. I will let my ears be the judge. Anyone here have any experience with these?

NOS Amp 7308s are a glorious tube. At least the Matched Pair I have.
But get the ones that have "PQ" or "SQ" on the tube, Premium/Special Quality.
With gold pins.

I use them in my Aesthetix Calypso PreAmp and my Manley Chinook PhonoStage.
They have more air, more body than the 6922 cohorts.

IMO, its just an all-around better tube:
More energy to give airy-er highs, more liquid (but not liquid like Mullards) mids, and the bass is "full", whereas
the 6922's bass is more taught but more lean as well.
The 7308s have a tad more gain than the 6922z. Im assuming this has a little bit to do with the numbers:
6922=6v or 6.3v
7308 = 7v.

It really does make a difference.
Another example is the 6DJ8s vs 7DJ8s, which of course are in the same family as the 7308/6922.

will talk a bit more about this re: the other post re:7DJ8

[who?me?]

A guy I know told me a sad story about these tubes.  They used to use Amperex JAN 6922 and 7308 in military equipment.   He heard about the military liquidating some large tube stockpiles in the 1990s.  His buddy needed 6DJ8 equivalents and loaded up a bag full of them.  They were heading out and passed some 55 gallon drums filled full of tubes, heading for the landfill.  Two of them were filled with these Amperex and they were told to take whatever they wanted, all new still in their boxes.  My friend put a dozen or so in his pockets just in case he might need them someday. 

Who knows how many of these wonderful tubes went to that landfill?   Many hundreds.   Or how many worldwide met this fate. 

This is basically how I got mine too.  A different guy went to a different base and bought up a large stock of many tubes.   Including a lot of these 6922 and 7308.  Then he sold them for $8 each.  I bought 12 from him. 

And this is why they sell for $100+ today.

I think Im getting physically sick ...... threw away 55 drums of NOS gemstones?????? 

[who?me?]

LOL yah I bet prices were waaaaay better 15 years ago 

These weren't cheap, but not absurd.  I got them thru Upscale, which I know is usually the most expensive, but I haven't had any bad tubes from them, so I feel like I'm paying up to ensure that I get a good tube.  My amp was supposed to be here today, but it got stuck on severe weather up north, so I will have to find something else to do this weekend...

yes, you pay a bit more from Upscale, but Ive never had a problem with their tubes.

If you go to the Upscale site, you can see that whacky Kevin in vids blabbering about how good the Tungsram 7DJ8s are. He likes to brag that these 7DJ8s are so good that the engineers and Paul Gowan of PS Audio picked Upscale's Tungsram 7DJ8s to use as the default tubes in the BHK250. Ya, that's pretty big accolades.

Personally, Ive listened to a matched quad of these NOS Tungsram 7DJ8s from Upscale, bc I bought a Manley Chinook phono stage "Special Edition 2" from Upscale, which Kevin designed to use the quad of Tungsrams.

IMO, the Tungsrams excel in the highs and mids, but less so for the bottom end. The bottom end is there, but plays a more recessed role than the highs/mids. It is just lighter, and a bit soft/smooth (which isn't bad) just like the highs/mids. I think these Tungsrams would do better with a bookshelf system that already has limits on its low end (eg 45hz), in conjunction with a sub.

But the 7dj8s do hav a bit more gain and manifested details, attack/decay, etc than the 6dj8 tubes.
Again, its the 7volt vs 6v issue.

(Im moving and selling a lot of gear, including the Chinook phono stage above,
Email me for info, Thanks!)