Ref6 tube rolling

[Golum]

I've asked a question a while ago if anybody did some tube rolling with Ref6 and did not get any answer, hence i decided to open a new thread so interested might easier find it.
Anyhow, I have a great buddy of mine with BAT gear who several weeks ago did this exact same trick with his gear and was stunned by the change it happened. Namely he swapped 6n30 tubes (apparently super tube) with 6n6p tubes. As within my Ref6 I have the same tubes he advised to try the same. Of course I was reluctant/afraid to do so, so i did a fair share of exploring the web (no info regarding the 6n6p in ARC gear) and also talking with world class tube gear designers and they all confirmed that I can swap them without any issue.
Off to ebay and i got two tightly matched quads and used only 6 pcs for the line stage, as I did not touch the one in the power supply section of the preamp.
Have to say i was quite nervous before turning the preamp ON but as preamp warmed up without glitches moment of truth arise with turning the volume knob from 0 to listening level.
After several notes played I was already sure that something magical happened which left me in total disbelief. Totally different ball game. Music is just flowing, you can literally feel it and touch it, super palpable, notes seem to last longer, dramatically more fluid, you can feel the darkness between the notes and overall feeling is that preamp is much calmer in positive way - like it was super nervous before. Staging as well massively improved. Even my mother, who was at my place, just out of the blue commented wooow this sounds really fantastic now. I had the system on for like an hour to burn in the tubes so will play with it of course further but those babies are not leaving the preamp as to me now 6n6p really are SUPER TUBES.
All in all massive improvement on already great preamp - highly recommended.

PS I did not return the tube rings as i was instructed they are not needed in case of this tubes as they are not microphonic and the cooling is better without them...
Few pics will follow...

 

[Golum]

A bit more reading for curious:
http://www.lampizator.eu/UPGRADE/upgrade noval tubes to 6H6P.html

 

[murphys33]

Thank you for sharing. Is there any reason why you did not swap out the 6h30 tube to a 6n6 tube in the power section?

 

[Golum]

Thank you for sharing. Is there any reason why you did not swap out the 6h30 tube to a 6n6 tube in the power section?

I just did not see a reason doing so, as that one is not really deployed in signal path (i believe). So i rather kept it as is.

 

[wisnon]

6n1p may even better the 6n6p in the preamp.

 

[ingemar]

And now you have to replace the 6550 to a Kt90 and you will never look back to those 6550's

 

[Golum]

Sailor man any specific KT90?

 

[ingemar]

Hi.
I'm using Electro Harmonix with great succes,just 45 euros!!

 

[Golum]

Thanks! BTW would you have the same feeling about those 6n6p as I do? I’m still amazed with them...

 

[ingemar]

They are so good that i'm selling the remaining dr's

 

[murphys33]

I use a psvane kt88 in place of the 6550 to good effect.

 

[TLi]

I bought some 6H6P from eBay. They are used in my ARC Ref 10. Eight 6H30DR in the main unit were replaced with 6H6P.

They functioned perfectly. There was no problem with the swap. The sound is warmer than 6H30DR. Bass is stronger. I shall let them burn in for a few days before handing down my verdict, my initial impression is positive.

Thanks for the recommendation.

 

[Golum]

Glad you tried it and pls do write after several days your impressions.

Cheers,
G

 

[murphys33]

I bought some 6H6P from eBay. They are used in my ARC Ref 10. Eight 6H30DR in the main unit were replaced with 6H6P.

They functioned perfectly. There was no problem with the swap. The sound is warmer than 6H30DR. Bass is stronger. I shall let them burn in for a few days before handing down my verdict, my initial impression is positive.

Thanks for the recommendation.

Are they matched and does it matter if they are matched or not?

 

[TLi]

Are they matched and does it matter if they are matched or not?

I bought them unmatched. It doesn't seem to matter too much.

Ref 10 uses 4 tubes per channel. Each tube, in fact, is stereo which means it has two identical halves. So each channel has 8 parallel amp components to equal out. Of course, in theory, it is best to have matched tubes, but I don't think it make much difference after all.

 

[microstrip]

Are they matched and does it matter if they are matched or not?

IMHO it matters for the REF Anniversary and REF 10. The triodes of the tube are run in parallel and many tubes show severe mismatch between the triode sections. Even for 6H30s I always select them in a custom jig - I only get them from the usual reputed sellers but have to discard about 15% of them for non critical equipment. After this selection the 6H30's can run for more than 6000 hours. In my experience unbalanced tubes soon develop noise and show more distortion in measurements. The few tubes I got from Audio Research measure perfectly and are accurately mathced , but are very expensive.

 

[Golum]

Super easy to buy on ebay matched, even quartets from sellers which are reputable (which i did) and got written measurements for each tube on top, so in general why not to take them matched

 

[murphys33]

Many thanks for your views.

 

[LR319]

Super easy to buy on ebay matched, even quartets from sellers which are reputable (which i did) and got written measurements for each tube on top, so in general why not to take them matched

Very keen to try out on my ref 3 phono, any particular brand I should buy on eBay ? NOS or used ? Thanks.

 

[Golum]

There are no brands of 6n6p as they were only produced in USSR. Diff is that you may find them made in Reflektor/Saratov factory or Novosibirsk factory but i would not bother. Try to score the ones with gold grid. If of any help, I’ll post a link from the seller i got them from and he’s really a top notch one.
https://www.ebay.ch/itm/232146716260

Cheers,
G
P.S. If you’re buying more than a quad, just mention that you need two very similar quads ie matched octet - i actually got close matched Octet