Puzzling problem with 6SN7 adapter

[adamct]

Thanks, Grainger. But I'm just not interested in making any changes to the wiring in my Crack itself. I now have those oiler motor run caps installed upside down on the top plate, so flipping it over is a more involved process than in the past, and each time I open up the Crack I have to desolder the leads to my coupling caps and...and...and it's just not worth it to me. I have zero complaints about my Crack when used with 12AU7s. Trying 6SN7s would have been a fun distraction, but it's really not necessary and the prospects of significantly improving on my current setup seem low.

[Grainger49]

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fi244.photobucket.com%2Falbums%2Fgg7%2FGrainger49%2FSmiles%2FROLF.gif&hash=d8c25de5059c9863b539eef0d5a5f9c5fb975e51)

I get a good mental picture of the problem.  Your avatar helps too. 

[Chris65]

Not a 6SN7, but using the earlier 6F8G with a very high quality adapter. Works beautifully, & sounds wonderful.

[jt]

Where did you get the 6F8G adapter?

[Chris65]

I wouldn't really like to mention a competitors name on a manufacturers forum, but if you Google '6F8G adapter usa' it should lead you to it. They are made with high quality teflon sockets, gold pins, not cheap but much better than any of the ones out of China.
Can also be made to order in any configuration you want.

[SharkFist]

Just wondering if anyone has tried this method yet? (Using a DC adapter to heat the tube)

I have same problem as the OP. I'm using a 6SN7GT (Raytheon VT-231), and this adapter I bought off e-Bay: http://www.ebay.com/itm/1-convert-tube-socket-12AX7-12AU7-to-6SL7-6SN7-9-pin-to-8-pin-/281031554093?_trksid=p2054897.l5658 [nofollow] (which looks exactly the same as the one somebody else said worked fine for them)..... I can hear music with the adapter and the 6SN7 adapter connected, but there is a very loud staticky noise (about 60% as loud as the music at listening volume), mainly coming through in one channel (but easily discernible in both).

I've seen no definitive answer about how to get a 6SN7 working with my Crack (which has Speedball installed too). Works perfectly with 12AU7 inserted. I'd be willing to try modding it to support the 6SN7 but not unless someone is able to confirm it works, or at least draw some kind of a diagram for dummies (which I am in the context of this DIY audio world).

[i luvmusic 2]

 I'am using a old desktop power supply and voltage regulator to heat my 6SN7 it is quieter than those eb4y adapters most of those are noisy  i've been using this method before the crack.
(http://)http://cdn.head-fi.org/9/94/900x900px-LL-94f07ae2_DSC_3218.jpeg

[netosullivc]

Hi you post a link to the socket you used in the conversion to swap out the 9 pin to an 8 pin?
Thanks

[Colin]

Hi Adam,

I assume you ordered this adapter, right? http://www.ebay.com/itm/1x-6SN7-to-12AU7-Vacuum-tube-adapter-socket-converter-/300943315564?pt=Vintage_Electronics_R2&hash=item46119e926c

Try this one : http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=320659633166&ssPageName=STRK:MEWAX:IT#ht_1080wt_793

It looks cheaper and not as 'well-made' as the one you ordered, but it works well

Best regards,

This is a bad adapter. My crack sounds blur... Anyone have a parameter to build a better adapter?
Kratos.

[hemenabergaz]

I'll repeat (for about the 3rd or 4th time) that heating the driver tube with DC will eliminate the noise issue of these adapters, and can be done very inexpensively.

So, I also wanted to try a VT-231 and bought an adapter. There is indeed a noise issue for me as well, but at a very low level. I think I would like to try the DC heating solution. My question is: would it be possible to put together a rectifier to rectify the AC coming from the crack transformer, or does it have to be an additional transformer or wall wart? Thank you!

[Paul Birkeland]

Just use the wall wart to be sure it's what you need.  If the wall wart works, then we can discuss how one might get 6.3V DC inside the chassis.

[hemenabergaz]

Ok, working on it! Thank you!

[hemenabergaz]

The wall wart arrived, and I tried as you suggested. Unfortunately, this did not have any effect on the hum (which strikes me to be not so low anymore as I described previously). All my 12au7 are dead quiet and sound beautiful. Should I abbandon this experiment, or do you have other suggestions?

No worries, this is not life or death, just playing

Thank you!

[Paul Birkeland]

That's a bad sign for the adapter if a DC wall wart didn't help you out!  Do you have a link to the wall wart you used?

[hemenabergaz]

Yes, you can find it here. Was I too cheap?

http://www.ebay.de/itm/201201010078?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT