[toufeeq]

I'm curious if anyone has tried a power conditioner to solve the hum problem. A few threads on massdrop forums seem to suggest a power conditioner solves the issue.

 

[Keno18]

I'm curious if anyone has tried a power conditioner to solve the hum problem. A few threads on massdrop forums seem to suggest a power conditioner solves the issue.

I have the Furman M-8X2. It made no difference.

 

[toufeeq]

OK, I think I made some great progress here. I burned in the power and the driver tube for around 20 hours and my ears can hardly pick out the hum now. If I listen really really hard in a completely silent room I can make out a faint hum but it's no where close to how "bright" it was when I first started posting about it. The good thing is I got 20 hours of music listening out of it and didn't have to leave it running overnight as my suspicion was that the hum was originating from the power tube.

Thanks for all the help guys!

 

[DenverW]

Last night I spent about an hour running a 7236 Tung sol power tube with a Tung sol black plate 12bh7a (on a 12au7 to 6sn7 adapter from eBay).

Very nice! This outperformed my Tung sol brown base 6SN7WGTA I had been testing the night before, and found a bit treble harsh. The combo did not go quite as sub bass deep as the best 6sn7 tubes, but had a good controlled bass. Mid range was the highlight, as it was just that slight bit forward that I enjoy for my 80s alternative music. Clarity, tonality, and separation were all on the level as high end 6sn7 tubes. Leaned a bit more towards musical rather than analytical.

Over the next week I’m going to be trying out some different adapters and tubes; and although I’m not the best at describing and reviewing, I’ll post what impressions I can.

This tube was $10.50 on eBay. For the cost it now ranks as one of my highest quality to price tubes. Th adapter was from a seller named Xulingers (good response time and no doa adapters yet).

 

[JKDJedi]

toufeeq,
the Fitzmod should have been your the first thing to do. I get the feeling that a lot of you don't want to get into soldering. The Fitz mod is not hard at all and there are lots of visuals to look at at on You Tube. You would be surprised how buying a decent solder station can save you lots of money used to remedy non audio problems.

The one small sweet spot - use resistors to attenuate the pot/get rid of the pot and install a 50K Alps Blue transforming the sound by shunting the pot with Z foil resistors, take a look at www.world-designs.co.uk FAQ section, very clear instructions, do not use an Alps Blue by itself - you will be disappointed/buy one of Valab 23 step attenuators around $20. Get rid of the hum and open up the D/V with one of the pot options - then you will know just what the D/V is capable of.

My understanding is that all the mod does is get rid of the initial hum, that no audio gains are to be had, that in reality the lower end is minimised, that's what I'm getting from threads I've read on the subject. Anybody here who's done the mod experience that?

 

[DenverW]

Today I received my 7193 to 6sn7 adapter...and this one actually works! My initial thoughts: high marks to clarity and separation. I’m not sold on tonality yet, but the Ken rad 7193 I’m listening to with a 7236 tung sol power tube has a wide range, well defined.

Based on the sound of both the 12bh7a I’ve been listening to, and my initial impressions on these, I would wonder why so many are paying so much for some 6sn7 tubes. There is tremendous value in some of these less expensive options. The adapter and the 2x 7193 cost me a total of $35, and it’s compatible with the more expensive 6sn7 options. Also, it looks cool.

 

[JKDJedi]

Today I received my 7193 to 6sn7 adapter...and this one actually works! My initial thoughts: high marks to clarity and separation. I’m not sold on tonality yet, but the Ken rad 7193 I’m listening to with a 7236 tung sol power tube has a wide range, well defined.

Based on the sound of both the 12bh7a I’ve been listening to, and my initial impressions on these, I would wonder why so many are paying so much for some 6sn7 tubes. There is tremendous value in some of these less expensive options. The adapter and the 2x 7193 cost me a total of $35, and it’s compatible with the more expensive 6sn7 options. Also, it looks cool.

Yeah some of these tubes like the 7N7 are outstanding bargains, add the Fotons in there too, both are almost carbon copy in sound save the headroom soundstage to the 7N7. I'm curious about these cute little ( yellow minions) tubes, might grab the same ken rads, last time I looked thats all there was but Ken Rads, and I'm also curious as to which "expensive" tubes (in your possession) are you comparing these too?

 

[DenverW]

I haven’t determined my overall preference, but I’ve been doing comparisons with tung sol mouse ears, Ken rad vt 231, rca grey glass, and sylvania 3 hole bad boys. The Ken rad 7193, tung sol 12bh7a, and Phillips/amperex e80cc are all at least in the mix. It’s just yet to be determined where

 

[JKDJedi]

I haven’t determined my overall preference, but I’ve been doing comparisons with tung sol mouse ears, Ken rad vt 231, rca grey glass, and sylvania 3 hole bad boys. The Ken rad 7193, tung sol 12bh7a, and Phillips/amperex e80cc are all at least in the mix. It’s just yet to be determined where

Outstanding mix there. And for $35? The adapter itself is near that alone from what I'm seeing on eBay... You got a steal there. Nice grab! Where did you grab your adapter from? I'm afraid of the Chfi ones.

 

[DenverW]

Every adapter I've purchased from "Xulingmrs" has worked flawlessly; ebay seller. Takes about 2 weeks to arrive, since its from hong kong/china, but no issues. I've purchased one from ak_somthing_flagship_store and not only did it not work (huge distortion at the 9 pm mark) but they were annoying as anything about getting my refund. Never going back to them again. When I purchased the adapter was 23 and the tubes were 12, so its not thaaaat far off, but it does look like the price went up a small amount. I've become pretty good on the whole ebay thing, just takes patience. I got my Ken Rad vt 231 for 30, because it has a broken center guide post. Doesn't effect anything, I just have to make sure I line it up properly. Of all the tubes and adapters I've bought on ebay, only 2 have been faulty, and they both were refunded.

 

[JKDJedi]

Every adapter I've purchased from "Xulingmrs" has worked flawlessly; ebay seller. Takes about 2 weeks to arrive, since its from hong kong/china, but no issues. I've purchased one from ak_somthing_flagship_store and not only did it not work (huge distortion at the 9 pm mark) but they were annoying as anything about getting my refund. Never going back to them again. When I purchased the adapter was 23 and the tubes were 12, so its not thaaaat far off, but it does look like the price went up a small amount. I've become pretty good on the whole ebay thing, just takes patience. I got my Ken Rad vt 231 for 30, because it has a broken center guide post. Doesn't effect anything, I just have to make sure I line it up properly. Of all the tubes and adapters I've bought on ebay, only 2 have been faulty, and they both were refunded.

Thanks, I'll have to give Xuling another shot.

 

[Slade01]

Thanks, I'll have to give Xuling another shot.

Yeah. I got my adapters from xulingmrs as well...no problems and reasonable shipping time considering.

 

[DenverW]

On to my 2nd pair of 7193, the National Union. My impression after the 1st hour: these may be the best tubes I've heard yet. More to come.

edit: going to see if a CV6 tube will work with the adapter. Have a pair from Mullard on the way.

 

[cddc]

Got my Tung-Sol round plates 6SN7GT...Oh boy...it is simply the best 6SN7 ever made, period!

There is no way my Brimar 6SN7GT can compete with it. Price-wise they're similar, but TS round plates is way way way better, super clarity, super stage, super separation, super bass, man, this is simply the best 6SN7!

 

[cddc]

Wait...I haven't heard the ECC32 and B65 yet, so take it with a grain of salt