I don't think we have any adapters in the house. I think we were hoping that someone who had the adapters would rummage around the house to find a 6.3V wall wart to give it a try.
Puzzling problem with 6SN7 adapter
- Thread starter adamct
- Start date
Out of curiosity (I'm really not inclined to spend any more time on this experiment, since I'm perfectly happy with my 12AU7s), how exactly would this work?
1. Would the adapter have to be exactly 6.3V, or would 6V suffice? When you first mentioned this, I looked around for 6.3V PSUs and didn't find any (I'm not saying there aren't any, just that my quick search didn't turn up any at the time, other than DIY options).
2. What modifications would be necessary? I assume I would have to remove or clip two of the pins from the bottom of the adapter (and maybe cover up the clipped pins to avoid any risk of electrical contact with the relevant holes in the Crack's 9-pin socket), and wrap the exposed leads from the PSU around two pins in the 6SN7 before inserting it into the adapter?
1. Would the adapter have to be exactly 6.3V, or would 6V suffice? When you first mentioned this, I looked around for 6.3V PSUs and didn't find any (I'm not saying there aren't any, just that my quick search didn't turn up any at the time, other than DIY options).
2. What modifications would be necessary? I assume I would have to remove or clip two of the pins from the bottom of the adapter (and maybe cover up the clipped pins to avoid any risk of electrical contact with the relevant holes in the Crack's 9-pin socket), and wrap the exposed leads from the PSU around two pins in the 6SN7 before inserting it into the adapter?
adamct said:
Look for wall warts that are 6-6.3V and rated for at least 300mA. Something like this will work if you need to buy one.
To modify the Crack, snip the black/red pair of wires leaving pins 7/8 of the octal socket and heading to the 9 pin socket. Snip them off at the octal socket. Strip the wires back and solder them to the wall wart cord (cut the plug off, strip each wire back). Heat shrink the joints. It doesn't matter which wire is connected to the red, and which to the black when you're connecting the wall wart.
There's a very, very slight possiblity of needing to add a ground reference to the 12AU7's heaters, but I wouldn't worry about it unless you get unusual amount of hum.
-PB
Grainger49
New member
Adam,
If you have a Wall Wart that is 6V@1A it will float high with a lower load. These are not regulated power supplies. But if you use 6V instead of 6.3V I think you are still within the range of what was specified.
If you have a Wall Wart that is 6V@1A it will float high with a lower load. These are not regulated power supplies. But if you use 6V instead of 6.3V I think you are still within the range of what was specified.
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
New member
I get a good mental picture of the problem. Your avatar helps too.
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.
Can also be made to order in any configuration you want.
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 (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 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 (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
New member
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://cdn.head-fi.org/9/94/900x900px-LL-94f07ae2_DSC_3218.jpeg
netosullivc
New member
Hi you post a link to the socket you used in the conversion to swap out the 9 pin to an 8 pin?
Thanks
Thanks
Aeolus Kratos said: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
New member
Caucasian Blackplate said:
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!
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
New member
Ok, working on it! 
Thank you!
Thank you!hemenabergaz
New member
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!
No worries, this is not life or death, just playing
Thank you!
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
New member
Yes, you can find it here. Was I too cheap?
http://www.ebay.de/itm/201201010078?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
http://www.ebay.de/itm/201201010078?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
