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AUDIO FORUMS >> General Discussion and Support >> 807 to 6L6 Tube Adapter Woes
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Message started by Sai on 03/08/24 at 04:55:26

Title: 807 to 6L6 Tube Adapter Woes
Post by Sai on 03/08/24 at 04:55:26

Sad to report that my Torii MKV’s right channel is blown because of a bad 807 to 6L6 adapter. I bought used GEC 807 (ATS25) tubes which tested perfect on my TV7 tester. Issue is I didn’t test the tubes with the adapter (using maybe even just a 6L6 setting). That would have sniffed out the problematic adapter which Steve thinks has blown out a capacitor in my amp. Plugged in the 807 tubes in the adapter, turned on the amp, heard a pop through the right speaker and then a hum. Also, OA3s failed to glow while this was happening. Now the right front output tube won’t register on the tube bias meter with any tube.

Anyways, a $29 adapter has now likely cost me $$$ in shipping, stress, and repairs….My beloved Torii is headed back to the mother ship for TLC…

Title: Re: 807 to 6L6 Tube Adapter Woes
Post by safebelayer on 03/12/24 at 02:58:07

Hey Sai, had you used the adapter previously? Can you show a pic of the adapter or the link where you bought it? How old was it?

Sorry to hear of your situation. I think many of us are using those adapters and the potential for disaster is cause for pause. I'm surprised at the result. I thought the current amp designs prevent such catastrophe.

Title: Re: 807 to 6L6 Tube Adapter Woes
Post by Steve Deckert on 03/12/24 at 03:36:32

I had the amp on my bench today to verify the symptoms and will tear into it tomorrow to see what caused it. Stay tuned.

Title: Re: 807 to 6L6 Tube Adapter Woes
Post by Sai on 03/17/24 at 03:53:33

Thanks so much Steve for taking a look at it.
Looks like she’s back in good shape! Will be headed back in town on 3/22 when I will get a chance to listen to it again…

Got an email saying that the culprit was a fried resistor on the output tube socket.

Title: Re: 807 to 6L6 Tube Adapter Woes
Post by Sai on 03/17/24 at 04:09:03

Hi safebelayer,
The adapter was new and purchased from:
https://www.tubeman.com/index.php?l=product_detail&p=1343
The vendor was apologetic and did give me a free replacement. So not really actively warding people off “tubeman.”

In my case I tested the 807 tubes but not with the socket adapters on them. The tubes themselves without the adapter tested great on my TV7 D/U.

That said, highly recommend that you test your 807 with adapter on using 6L6 settings on your tester to see if the darn combination of tube and socket adapter works before plugging it in to your amp. This was suggested by Steve.
The objective of the test is to tease out if you have shorts or can register a reading. My tester showed that more than one tube did not register a reading with the faulty adapter.

Title: Re: 807 to 6L6 Tube Adapter Woes
Post by hdrider on 03/17/24 at 17:03:09

Sorry to hear about this Sai. I have been buying tubes off tubeman for at least 15 years when I had my ARC SP-12 (lots of 6DJ8's) and he's always been a great source. But I have not bought adapters from him. When I started using 807's in our Rachael, I bought three pairs, over time, off eBay and the offshore units were wimpy at best. I have had the wire break off the top cap, fixed them and they worked correctly. THE BEST adaptors I bought, and the only ones I use now, I purchased off of maximatcher at 99.00 each and took about 3+ months to get. Great product, built very very well, robust. The company itself left a lot to be desired in terms of customer service. When he finally responded to a email, he explained that they are made to order and that's just what it is. OK, it was worth the wait. Just thinking about it, I will order another set, forget that I ordered them and in 3 or 4 months they will show us. If anyone wants a set of the chicom adapters, shoot me a PM and I'll get them posted, and I won't take as long as maximatcher. Sure wish I had a tubetester....Happy Listening, Chris.

Title: Re: 807 to 6L6 Tube Adapter Woes
Post by Sai on 03/19/24 at 01:44:40

Thanks for sharing that info Chris. Will definitely let you know if the new adapter I bought doesn’t work. I agree, I think Tubeman has a great reputation. It was just pure bad luck that I got a bum adapter. Anyways, hoping the new replacement he sent works out.

Title: Re: 807 to 6L6 Tube Adapter Woes
Post by Sai on 03/19/24 at 03:05:13

Chris, would you be able to post a pic of the maximatcher adapter? Just trying to see the difference in construction quality between it and what I bought. I’ll do the same, and maybe post a side-by-side view of the two adapters…

Let me know. Thanks!

Title: Re: 807 to 6L6 Tube Adapter Woes
Post by hdrider on 03/23/24 at 15:18:11

Sai- Sorry for the delay in this reply, but it's been a busy week at work with old machines leaving to make room for new mills and lathes.
Hopefully this photo uploads. The adapter looks similar to the off shore units we've all bought off eBay and others. Just a lot more beefy. The wire to the anode cap is five or six time in diameter, the connection inside the cap is well soldered and that area is filled with what looks like a white epoxy? Does it sound different? Don't know and something I would dive into. If it's built better, it's gotta be better...22+ years in machining has left it's mark. Again, sorry for the delay and I hope you have a great weekend and Happy Listening.