[NightFlight]

Mystery tubes always sound better. LOL. I had this GE that blew me away for quite a while, but eventually I rolled it. I still haven't gotten the 12BH7A out of my crack pre section.. but I've not turned the crack back on since I built the Mainline.... I've got to try an E80CC before the good ones vanish. 
 
But yes, that Harleen plant has something magical about it. A proper 60's era grey shield 6922 Siemens & Halske in a Lyr will make you sit up an notice too. Blink. Then notice again. Repeat.

 

[DDDamian]

Nice find Kratos - whatever it is lol. I'd say send the pics to one of the bigger tube sellers (Tube Depot, etc) and see if they can give a positive ID. The codes you see on it will help. Let us know!!

 

[moriez]

  Mystery tubes always sound better. LOL.

 
My thoughts exactly. The very effect unobtanium would have on me. Oh boy ^^
 

  I'd say send the pics to one of the bigger tube sellers (Tube Depot, etc) and see if they can give a positive ID. The codes you see on it will help. Let us know!!

 
Another effect of reading great enthusiasm is contagiousness. I believe at Vacuumtubes.net they're very knowledgeable and at Upscaleaudio seems a great guy. Give it a shot AK.
 
 

 
I rolled in this Valvo E80CC but it's too smooth for my taste and prefer the CBS Hytron 5814 to it. Basically a good bit more air and detail to be heard. If there's anyone who wants to swap one of his tubes or wants to buy the Valvo off me send a PM. 

 

[Mich4lle]

Hello everyone,

I am sorry that I am not the most helpful member and always need help but I have a new problem.
So I am going to start at the beginning,
A couple of months ago the bolts that hold my RCA jacks to the chassis plate gave out and the RCAs shorted out against the chassis plate, which caused my crack to go quiet with some distortion in the background.
I then ordered new RCA jacks and installed them when they came. The new RCA jacks were a bit wider than the stock ones so I had to drill out the hole a bit. After this my crack worked for half of a song and then the signal slowly started distorting and by the end of the song there was basically no signal coming though. I then resoldered the RCA jacks and this made no difference. I then realized that the new Jacks needed an even bigger hole because they were still touching the chassis. I drilled the hole bigger and the RCA jacks then seated properly in the chassis.
After this the signal louder but was still fairly distorted. I then resoldered the jacks again which made no difference.
I then turned the crack off and tried again the next day, it played perfectly for half a song again and the signal started degrading again to a point where there was almost no output.
This led me to believe that the problem is the power tube, because at this point there is nothing wrong with the RCA jacks that I can tell, and there is a worrying rattle coming from my power tube when shake it.
Am I right to think that the power tube is the problem?
Thanks in advance for any help, if I am unclear somewhere please let me know so I can clear it up.

 

[DDDamian]

Hello everyone,

I am sorry that I am not the most helpful member and always need help but I have a new problem.
So I am going to start at the beginning,
A couple of months ago the bolts that hold my RCA jacks to the chassis plate gave out and the RCAs shorted out against the chassis plate, which caused my crack to go quiet with some distortion in the background.
I then ordered new RCA jacks and installed them when they came. The new RCA jacks were a bit wider than the stock ones so I had to drill out the hole a bit. After this my crack worked for half of a song and then the signal slowly started distorting and by the end of the song there was basically no signal coming though. I then resoldered the RCA jacks and this made no difference. I then realized that the new Jacks needed an even bigger hole because they were still touching the chassis. I drilled the hole bigger and the RCA jacks then seated properly in the chassis.
After this the signal louder but was still fairly distorted. I then resoldered the jacks again which made no difference.
I then turned the crack off and tried again the next day, it played perfectly for half a song again and the signal started degrading again to a point where there was almost no output.
This led me to believe that the problem is the power tube, because at this point there is nothing wrong with the RCA jacks that I can tell, and there is a worrying rattle coming from my power tube when shake it.
Am I right to think that the power tube is the problem?
Thanks in advance for any help, if I am unclear somewhere please let me know so I can clear it up.

If it works for a while and then displays the effects you're seeing then the tubes are one possible cause. A bad solder joint somewhere could also cause this (as a component warms up a bit and the connection worsens). Is it both channels or just one?
 
Perhaps try the following:
- try a different source
- removed both tubes and inspect the pins for oxidation / discolouration. Gently clean with a small wire brush available at most dollar stores and re-seat them into the sockets
- while their out carefully inspect them under the light and look for any connection issues inside - jiggle them a bit
- power-up and note the intensity of the tube heater filament - does it change at all when the signal starts to distort?
- after the power has been removed for a few minutes carefully inspect your solder joints everywhere. If this is happening to both channels I would suspect the power supply circuit or heater circuit, or the signal ground. If only one channel focus on the signal wiring for that channel
 
If the above fails then grab a set of tubes off EBay or elsewhere and swap them out one at a time.
 
If you still have no luck at least you'll have been able to rule out the obvious. Post in the appropriate Crack subforum over on the Bottlehead site, and be as specific as possible, including a concise statement of the effect (and whether it's one channel or both) along with what you've tried. Guys like P Joppa and Caucasion Blackplate there know the Crack inside out. A well-worded and concise post will often get a good reply within hours, but they need good info!
 
Good luck

 

[Mich4lle]

Wow thanks for the great reply.
 
The problem is across both channels and when I started it up today, there was just distortion straight of the bat, so I couldn't note a change in filament glow.
In fact the signal barely came through at all. As far as I could tell the soldering was fine, So I think that it is the Power tube because it does have a bad rattle when I shake it gently.
I have order new tubes and they will get to me soon. I just want to know if it will be safe to put them in the Crack, what if it isn't the tubes and the new ones get damaged, is that a possibility?

 

[FunyunBreath]

I'd order some cheap tubes just to have on hand in addition to the new one's you're getting. I like to have a cheap 6080 and 12au7 on hand for use after I mod the crack and want to make sure everything is in order without damaging a 5998 or something.

 

[Aeolus Kratos]

  Maybe a ribbed plate Telefunken? If there's a diamond stamped into the glass on the bottom of the tube thats what it is. Construction looks almost identical to my smoothplate Tele.
 
Also if you don't plan on using that Mullard CV4003 and it's in good shape shoot me a PM, I'd definitely be willing to make you an offer for it

Hi FunyunBreath,
 
Thank you for your offer, unfortunately, I gave my CV4003 to another audiophile friend.
 
Cheers.
 

  Nice find Kratos - whatever it is lol. I'd say send the pics to one of the bigger tube sellers (Tube Depot, etc) and see if they can give a positive ID. The codes you see on it will help. Let us know!!

 
 

   
My thoughts exactly. The very effect unobtanium would have on me. Oh boy ^^
 
 
Another effect of reading great enthusiasm is contagiousness. I believe at Vacuumtubes.net they're very knowledgeable and at Upscaleaudio seems a great guy. Give it a shot AK.

Hi guys,
 
I'm just so glad that you guys gave me some really great advice and ideas. Thank you so much for that!
 
And I'm very happy to confirm that I got my answer that I need. And I want to echo the excellent identification of this guy as he did give me an EXACT answer:
 

  I think you may have stumbled upon an old Amperex Foil Strip D Getter. If so, that's a nice find. Enjoy.

 
I sent an email to all the big tube dealers in the world as well as in my country and it seemed like I've got the same answer. Here is what tubedepot sent to me:
 

I could be mistaken, but I think what you have here is an Amperex
12au7 Hamburg D-Getter that was actually not manufactured by Amperex
but by Valvo in the early 50's. No guarantee, but it looks exactly
like one, and these guys are truly rare treasures, so it's certainly
where I'm putting my money.

 
According to some tube dealers in my country and tubedepot, I really do believe that the unknown tube that blew me away is an Amperex (or Valvo) 7316 early 50's long plate foil "D" getter (with the "Ct0" code).
 
Based on my own experience, I just can't recommend this tube enough for the Crack. I have to admit, I've tried MANY different input tubes in nearly ALL tube types for my Crack for the past few years (6SN7s, E80CCs, 12BH7, 12AU7 variants...) but none of the tubes I've tried can compete with the Amperex 7316 long plate "D" getter.
 
I did some critical listening and comparisons between all the tubes I currently have in my collection (all the tubes I consider "best" before) over the last few days so I'm sure what I've heard was not my imagination. The 7316 sounds absolutely sublime with both my Bendix 6080WB slotted graphite column and Tung-sol 5998. The Amperex 7316 is truly an end-game tube for me, and the fact that it is an 12AU7 (which can be directly used with the Crack without any modification) is another plus. Get this tube and you no longer have desire for tube rolling anymore.
 
One minor thing I want to add, from I've read, Amperex 7316s have many versions - long plates, short plates, "O" getter, halo getter, "D" getter, year of manufacture...my tube is an Amperex 7316 early 50's long plates "D" getter, so my experience and recommendation are just based on my tube. I can't be sure that all the Amperex 7316s sound the same.
 
Best regards,
Kratos.

 

[DDDamian]

Great that you got a positive ID (JohnBal was right on the money!). Off to scour my usual sources for one......Hope they don't read your post or the price will triple lol.
 
Thanks for sharing your find and congrats!
 
EDIT: wow - they are very expensive. Described by some as the "Holy Grail" of 12AU7's. Super-nice score 

 

[FunyunBreath]

Mannnn I had an opportunity to pick up a 7316 one time for like $75 bucks and passed on it... Now i'm kicking myself.
 
Off to look for one as well haha, thanks for the update!

 

[moriez]

A good read A K. I wish you a great time with it

 
It has me pretty hyped up and to tell you the truth, I already butchered the internet to find one. The only thing that seems to be coming really REALLY close is an auction that started just yesterday! Place your bets gents. All in?

 

[Aeolus Kratos]

  Great that you got a positive ID (JohnBal was right on the money!). Off to scour my usual sources for one......Hope they don't read your post or the price will triple lol.
 
Thanks for sharing your find and congrats!
 
EDIT: wow - they are very expensive. Described by some as the "Holy Grail" of 12AU7's. Super-nice score 

Hi DDDmanian,
 
I actually just searched the price of the tube I have, and I was...speechless. These 7316s cost a small fortune!! And I'll definitely not tell my audiophile friend (who I bought my tube) the actual value of the tube he sold to me 

 
Warm regards,
Kratos.
 

  Mannnn I had an opportunity to pick up a 7316 one time for like $75 bucks and passed on it... Now i'm kicking myself.
 
Off to look for one as well haha, thanks for the update!

Hi FunyunBreath,
 
You're very welcome.
 
Cheers.
 

  A good read A K. I wish you a great time with it

 
It has me pretty hyped up and to tell you the truth, I already butchered the internet to find one. The only thing that seems to be coming really REALLY close is an auction that started just yesterday! Place your bets gents. All in?

Hi moriez,
 
Thanks for your kind words, I really enjoy my Amperex 7316 very much 

 
As for the bid for the Amperex 7316, it looks like the tubes in your link are the tube I currently have.
 
 
Below is a pair of the 7316 in the link you posted:                                 

 
And this is my tube

 
So it seems my tube exactly is the same as the tubes which are on sale and more importantly, is exactly an Amperex 7316 long plates "D" getter.
 
I strongly recommend you get this if you can afford it (although I got my 7316 for much less but I really think the ~$100 price tag for each of these is really worth it)
 
Happy bidding and good luck!
 
Regards,
Kratos.

 

[DDDamian]

Reserve not yet met 10 bids in  
 
Not sure if I'll join the bidding on those, but prices for a single out there are easily USD$225 from reputable dealers, tested NOS. Good luck to anyone bidding! Would love to trip across a box of them in some forgotten Eastern European warehouse - retirement would be that much closer 

 

[Oskari]

  I tried my best to picture all angles of the tube. The tube has long grey plates and D getter, with the code says "48L" and "47H".

 

  According to some tube dealers in my country and tubedepot, I really do believe that the unknown tube that blew me away is an Amperex (or Valvo) 7316 early 50's long plate foil "D" getter (with the "Ct0" code).

 
Can you verify the code?

 

[Aeolus Kratos]

   
 
Can you verify the code?

Hi Oskari,
 
The particular my Amperex 7316 has ALL the codes on the tubes, all the codes were printed on different places on the glass. But you should stick with the "Ct0" code only.
 
Cheers,
Kratos.