1101 Audio custom crafted headphone amps
Jul 31, 2023 at 3:55 PM Post #1,201 of 1,210
Aug 3, 2023 at 4:02 PM Post #1,202 of 1,210
Been rolling with the Telefunken 6080's lately. The Telefunken's sound great with all of the drivers I've tried in the BH+. Today I went full on German with an early RFT ECC82 (foil getter) in the driver seat. Absolutely dreamy soundstage and timbre with with the AC - that bass!!

(Pins were cleaned before using!)
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Aug 22, 2023 at 8:09 PM Post #1,203 of 1,210
It's been quiet here... hope 1101 amp owners are enjoying their gear. Last few weeks I've been listening to the Atrium Closed with the BH+ and 12AU7 and 12BH7 tubes via 6SN7 adapter. 12BH7 have been interesting to try. These CBS-Hytron black plates have a very airy and open stage, but are somewhat thin sounding on their own. Adding a pair of 6J5 (Fivre 6J5GT gray plates) and running as a driver triplet seems to add the thickness/density that was missing.

For power tubes, so far I've tried the Telefunken 6080, Bendix 6080WB, and Raytheon 6336B. All have slightly different qualities with this set of drivers. Bendix is the warmest and smoothest listen. Telefunken 6080 is balances things out a bit and is very enjoyable. My favorite combination currently is with the Raytheon 6336B. It brings the most clarity, immediacy, and spaciousness. Probably the most "life like". The Atrium Closed sounds SO good with the BH+ in general, I don't think I'd be able to say one combination is objectively better than another. They are all very enjoyable - just different flavors of the week.

edit: for those in the BH+ queue, I highly recommend the upgraded power tube regulators! The 6336 and especially 6528 are something special.

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Aug 22, 2023 at 9:51 PM Post #1,204 of 1,210
Sep 19, 2023 at 1:24 AM Post #1,205 of 1,210
Really enjoying this combination with the Atrium Closed tonight. Power tubes are Chatham 6520 that seem to have similar construction to the 6AS7G. At first I tried the Russian 6S5S (6C5C) as drivers and the synergy was not there. As an aside, 6S5S sounded pretty great on their own in BH mode (goes to show how much synergy matters!). Not many tube combos in this amp drive me to make an immediate change, but this was one of them. Thumpy and congested sounding. Bring on the the G-73R which is totally hitting all the right spots. The stage opened up massively in all directions and there's now an enormous amount of detail and clarity. Awesome bass texture. The smoother 6520's add warmth and decay that compliments the Telefunken in all the best ways. Currently in Knight Rider mode with the black coated glass tube and K.I.T.T. style VU meters - had to turn the lights up a bit to take this pic:

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Sep 27, 2023 at 2:17 AM Post #1,206 of 1,210
Any internal pictures of the blue halo+ and blue halo stock
Nov 7, 2023 at 6:59 PM Post #1,207 of 1,210
Tube rolling journey chronicles continue. I have been trying out the 6J7 -> 6J5 adapters made by 1101 Audio. These adapters are very high quality. I think they are nicer than any other adapter I have tried (including ones made by a certain head-fi'er).

First up: EF37A

After trying 4 different tubes with the signature "Mullard Red" coating, I found only 1 to be silent, 2 to have noticeable noise floor, and 1 to be totally dead. Bummer. Fortunately I had this gray coated NOS pair that are dead silent.

Sounding very nice! Smooth and detailed with great soundstage. Remind me of some of my favorite L63.

Next up: KTZ63!

Having some fun playing with the new iPhone 15 Pro camera settings/lighting:
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Nov 14, 2023 at 1:31 AM Post #1,209 of 1,210
I'm having more trouble than I thought I would moving on from the EF37A family. I had forgotten about these Cossor OM5B and OM5C tubes. They are based on Mullard's design and electrically identical to the EF37A. Likely manufactured by Mullard (read more here). Not going to win any beauty contests but man do they sound good. They make for a killer combination using Blue Halo mode with the VC. Has anyone else tried these or the EF37A before in their amps?


Nov 15, 2023 at 4:44 AM Post #1,210 of 1,210
I’d like to try these tubes if I could get my hands on the adapters. Currently still rolling a bunch of different 6J5 tubes in my BH+ amp whenever I have the time for a little R&R. They sound fantastic.

BTW, thanks for the recommendation @raindownthunda !

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