Rolling 6SN7's in the A30

[Gromit]

I'm after some 'better' 6SN7's for my Puresound A30, and having owned one of these beasties before and used Sylvania Bad Boys in it, am well aware that it does respond - very favourably - to better ones.

Of course I could just get a pair of BB's but they're getting hellishly pricey these days so would rather stick to less expensive stuff. The amp's presently wearing a pair of EH SN7's (non gold-pin) which seem ok, but I'm after trying something different.

There are a few black-plate Sylvania SN7GT's on the Bay of E which could be worth a shot? If anyone has any other recommendations, please just shout up.

The rectifiers could be looked at too but I wasn't 100% sure the last time when trying some Mullard GZ37's.

Thanks!

 

[Jazid]

PM'ed :^

 

[wizmax]

After trying several 6SN7's in my 845 power amps and Icon Audio PS3 I have finally settled on TJ Full Music versions they sound great and look great.

 

[hifitony]

Hi Richard, I can recommend Sylvania 6SN7 GTB marketed under the BALDWIN name, who were famous for Organ making - supposedly a higher quality version, and replaced my stock EH Tubes - my pre uses 6 tubes 2for left, 2 for right channel and two for the balanced input. I also use now use 4 of the baldwin on the left and right channel inputs and 2 RCA 6sn7GTB's on the balanced input - a much more dynamic and smoother sound.

 

[Lefty]

Good thread - I'd be interested in people's views too. I've gone straight to Sylvania 'Bad Boys' in my A30 but as Gromit says, they aren't cheap!

It would be good to know what else is around for sensible money.

Lefty

 

[Gromit]

Thanks chaps.

James (Jazid) has pm'd me with a couple of choices which could be worth a shot. Pete (Coco) very kindly sent me a few to try some years ago with my old A30 and it was very interesting comparing various types. For me, the Sylvanias tended to be the best choice - even if they weren't the full-on Bad Boys. The BB's were the best though, sounding crisp, tidy and full of colour - sure they aren't cheap (I paid something like £90 for a pair sent from the US) but I feel they're worth the outlay.

Least favourites were Brimars which were a tad cuddly. Tall-bottle Sylvanias were superb, and not that far off the BB's, as were some Ken-Rads.

 

[Baggawire]

My Canary amp uses a pair of 6SN7's and whilst I've not had experience of any modern versions I've used a few NOS. The only valves I didn't rate were chrome top Sylvania's which sounded very bright and brittle. RCA 6SN7GT and Sylvania 6SN7GTB's are pretty good and don't cost the earth but the best I've used are RCA VT231 smoke glass. There's not a lot in it but the sound from the VT231s is fuller and more rounded. They're not cheap though.

 

[colesey]

I've used a few of the renowned nos 6sn7 (rca vt231 black plates / TS round plates) in a few different circuits but would recommend you check out both psvane cv181 and melz 1578 (drilled holes on plates) - both of these sound better to my ear.

 

[hifitony]

I have also heard that the CV181.s are good, but be careful if your valve goes in through a top plate as the bases are bigger than standard valves - I bough a matched quad and they would not fit through the cut-out of my pre - sold them on easy enough - but forewarned is forearmed

 

[Jazid]

The Melz come with a big reputation, I've never seen any in the flesh.

It's worth mentioning that the valves, whilst being freely interchangeable, are not exact equivalents. The GTA/B variants are more powerful than the original GT. Amps designed for the GTA/B types will run the older VT231 typeGTs very hard, their life will be glorious but rather short. Amps designed for the original GT types will accept all other kinds without issue, indeed the newer variants will last much longer as they are being barely stressed.

As such, and solely in my humble opinion, the GTA/B variants represent rather better value for money, whilst the august and venerable smoked glass VT231s (and now the Chrome Domes and Baaad Boys) are relatively expensive unless you can guarantee provenance, strength, and balance between sections. Plus I have read microphonics can be an issue, summat to watch out for with eBay 'NOS' tubes I suspect. So saying I have quite a lot of these, but no amp to listen to them with, so my comments are related to emissions, Gm, and hours of useful life per squid spent rather than timbre, tonal accuracy, dynamics, etc which I cannot therefore comment on.

 

[colesey]

James, I'd say the melz and psvane have more in common than differences in terms of both sound quality and presentation. Tony raises a good point regarding the size of the psvane - they wouldn't for example fit into the tube 'tunnel' of my Lampi dac.

 

[Gromit]

Thanks for the info guys - makes for very interesting reading, especially to a total valve-numpty like me who knows diddly-squat about what does/doesn't work.

I might get Guy to confirm the GT/A/B suitability for the A30 (ie how hard it drives its valves).

Next thing will be the rectifiers but that's for another day...

 

[mr.me]

I have a pair of the Melz (drilled holes) if you are interested but they are not cheap

 

[mr.me]

Having said that some of the most musical 6SN7's I've had are the Shuguang 6N8P. There are a number of variants of this tube but the ones I am referring to have dimpled chrome tops and a chromed metal base as can be seen in this photo:

 

[Jazid]

I have just turned up a couple of early 1970s Chinese 6N8P tubes, metal bases. They are built really really well, and measure superbly. Anyone got any experience of what these sound like? They don't look like the current Shuguang crop, more mica, tighter construction, plates rather lower in the tube.

PS for Mr Mr Me I might be interested in the Melz tubes if Richard isn't PM if appropriate :^

- - - Updated - - -

Beat me to it! Those 6N8P are the ones I am talking about I believe

 

[speedysteve]

My experience is that using different tubes for the splitter pair and driver pair gives me more flexibility and fun!

I too started out with a couple of loaners from Mr Coco - what 10-11 years ago that was!

I used various 6SN7's in a KT88 power tubed amp for many years. In fact Gromit, you may have heard that amp way back into a pair of Tannoy Berkeleys you came over once - things have moved on a bit since then though

I bought all of them, apart from the Electro Harmionix's, 2nd hand on eBay.

Didn't have a single duff one... They all still work fine. Come from all over, UK, US, Aus.

I used to have these in stock and change occasionally or when I was bored but eventually settled on a definitive 6SN7 config for me:

Kenrad black glass, bottom getter, yellow label - Used a pair of them as driver tubes for a long time. Warm, fluid full bass sound. Had 4 but only ever used 2 as it's all too warm with 4 in.

National Unions - Bit more mid range than the Kenrads, goodish bass. Again driver tubes.

Electro-Harmonix gold - Nice all rounder - used again as drivers.

Sylvania green label, bottom getter - Quite bright sounding, good highs.

Had 4 but was too bright with 4 in. Used as splitters with Kenrad drivers or as Drivers with the Raytheon's.

Sylvania white label VT-231 Jan's, bottom getter - Very lively and bright.

Amazing - plug in a 1941 tube and wham bam, god they're alive! Only ever tried them as splitters. Would suit a dull sounding system / room with all round thick carpet!

Raytheon yellow label, side getters - not as bright as Sylv greens or whites - used these as splitters with the Electro's. Nice mellow but detailed sound.

GE side getters - not bad, not that much going on though.

Sylvania brown base - my favourite splitter tubes. I teamed them up with the Electro Harmonix's for ages.

I then modded the amp to reduce gain for use with more efficient speakers and only had one 6SN7 tube stage and used the Silvania brown bases on there own. Perfect for my use.

These were my favourite all rounder 6SN7.

Tubes I've since sold on

RCA bottom and side getters - did not get the hype. Even the staggered grid ones.

GEC Light show tubes, have a filament across the top - very pretty but fairly dull.

Chelmsfords own - matched quad. Work ok but outshone by the above ones I've kept.

Sovtec's - bought them as part of the amp build. Work fine but are bettered.

Kenrad black glass - got a good price for them.

National Unions - got a good price for them.

Raytehons.

Never owned - Tung Sol black. They are supposed to be the biz - shame on me - should have bid harder.

 

[Gromit]

Thanks for the gen Steve - and yes I well remember popping over to yours some years ago.

 

[Jazid]

Anybody with experience of the true Chrome Domes and Mouse Ears? There's a bit of a rustle in the bustle about them as well...

Oh forgot- Steve, what you could get 10 years ago on eBay and what turns up afordably now are not related I am miserably sorry to say. I stopped buying 6SN7s on the bay a year or two back. I don't know if you do this but I measure all the tubes passing through and found the reject rate for the eBay sn7 variants was getting rather close to 100%. They all 'work' but they aren't usable due to section balance, etc ,etc. Same thing for EL34s amongst others IMHO.