Telefunken Black Diamond Power Tubes
 

Anyone tried the new Telefunken Black Diamond power tubes? See them in KT88 and EL34, but there may be others. Wonder who is making them.

Glenn.......Telefunken Elektroakustik is the company name, a partnership with JJ tubes. The Telefunken Elektroakustik Black Diamond tubes are essentially JJ tubes that have been cryogenically treated, silk screened in black with the Telefunken logo, tube designation, and sold in Telefunken packaging. They are definitely not Telefunken old stock tubes made in Germany. These tubes are being manufactured in Slovakia.

I have not tried the Telefunken Elektroakustik Black Diamond tubes and probably will not due to JJ's reputation of short lived tubes. If they eventually prove themselves a worthy valve contender with positive reviews perhaps I will change my mind but for now I will continue to roll with Gold Lion.

Thank you for the information, Dan. Good to know. With New Sensor resurrecting the Tung-Sol, Genalex and Mullard badges I would've guessed it was them.

Unfortunately, JJ's rep precedes them. Was hoping for a worthy replacement for Winged 'C' tubes now that they've gone the way of the dodo. With the small price delta between their EL34s and the "known good" brands, may give those a try.

They are JJ tubes that have been, allegedly, rigorously tested and cryoed.
However, I have not used them. I have used and really like the ECC803s but I buy from dealers that do further testing. The QC at JJ has improved considerably. I have tried the JJ KT77's, 6V6's and 6CA4's. They can be very good in the right system. I find them to be a bit darker than the Gold Lion tubes.

I had a pair of 12AX7 Black Diamonds in my C2300 preamp; took them out last night. Except for the fact that they weren't too helpful with the brightly-recorded older stuff I sometimes play, I thought they were pretty good. They're brighter than the JJ ECC803s (everything I've tried is), but the BD's lower frequencies were nice. Not quite as robust as the JJ's, which is a bit forward, but satisfying nonetheless.

Black diamond 12ax7s
 

This is an old thread but I thought I would and my 2 cents, which with inflation is 1 and 1/2 cents. I have tried the BD 12ax7 in my ARC SP 8 and in the 12ax7 slots in my Mc 275 IV's. In the SP 8 they did very well. A clear, neutral sound similar to real Telefunken 12ax7's. They lack the dynamic jump of the real thing, but that pre-amp has plenty of jump of its own. No complaints.
I never tried the power tubes.
Main complaint of the 12ax7's is the price, about $44 a piece. Too much IMO. If they were about $26.95 or so, then one could take a flyer on them, but at $44, not so much.
In the 12ax7 slots in the Mc 275's they were good, but an RFT in the first position gave more drive to the sound. Oddly, I did not care for the RFT's in the SP 8, not enough sound=stage and depth in that application.
Hope this is of value to someone.

Re-reading this thread and the comments on the BD tubes, perhaps I will try mine again at some point. Changes have been made to the system since last year, with power cords and interconnects from Transparent. These improved things (the power cords in particular), and perhaps the BDs will have a friendlier environment to work in. If I do make the switch I'll post on it. Before, with mostly Kimber ICs and Wireworld PCs the BDs had a crisper sound than the JJs and, as I said before, a good bottom end, just not quite as weighty as the JJs; maybe it would be better now.

I have installed the Black Diamonds in my C2300, in the line stage and the MM phono stage. I'm liking the sound. The low end is satisfying, and there has been a bit of detail here and there I don't recall hearing before. It's a small sample perhaps, about 3-4 hours of CDs, DVDs and BDs. No LPs played yet, as the Aragon 47k phono stage I was using has been disconnected due to a system reconfiguration. I plan to play some LPs eventually, though, and I'll be going straight into the 2300.

JJ's QC has really improved. I have had no issues with the KT77's.