Great tube amp...advice needed

Interesting.. I had also earmarked Mjolnir2 for my amp and was saving for it.. My DAC is NAD M51. Phones HD650.

Lets see how this thread develops.

 

Are you sure the Stratus works with 6922 tubes? AFAIK it uses a different input tube. Have you actually heard a Stratus with you own ears?

As for Gungnir Multibit, where did you get this info about the tube output upgrade (and the fact that only SE outputs are available with it)? Is it for Gungnir Multibit only or Yggdrasil too?

 

A fair number of tube amps have balanced outputs through the use of center tapped output transformers - e.g. mainline offers this as do multiple amps in DNA's lineup. I guess the key question for Ice-Man is which of the factors in the OP rank highest. E.g. do you care most about having a true "tube amp" or having differential gain stages? If the latter, I'd go with a T3, even though it appears to be single ended from the outside. If the former, I'd recommend building your own mainline. It is an incredibly satisfying project and an exceptional value (I would argue unparalleled among tube amps) - the end result producing wonderfully clean single stage tube sound, designed by the guys who created the parafeed topology (and derived from Doc B's $7k statement amp).

I'd avoid becoming wedded to any particular set of tubes. Their life is finite, and the circuit around them is far more important. If you must have a balanced input, you could always consider a bal-se transformer box like the one Marv links on occasion.

 

Thank you kindly for all the replies and advice. Looking carefully at several options.

 

T3 with cinemags and Mundorf caps will get you most of the way there, super pleasant sounding. TomB built mine with those upgrades and it works great. He might also have ccs boards to install as well. Haven't heard it with ethers but is amazing with dynamics.

Been curious about mainline, lots of people are happy with it, but seems mostly geared towards dynamics.

Stratus is lovely and versatile but the recent used ones have gone for 2400, which is above the OPs stated budget.

Oh there's a Crimson on headfi for 1900, I'd be tempted but no budget atm.

EDIT: MisterRogers used his T3 with a Gungnir Multibit and HE1k I believe and had gave lots of praise to the combo. I use it with Gungnir Multibit and 650/800 and it's phenomenal.

 

^^ thank you Brencho. If the T3 can drive Ether then it would be a sure thing for me. If MrRogers was able to drive HEK then I'm all set. The Ether is a cupcake compared to HEK when it comes to drive-ability.

 

I have not tried, but socket is same and the specs are not so different that it could harm the amp. Will try this later out!
I have Stratus. Just got one! First impressions are very positive, best amp for vocal and jazz music by far. For rock i still prefer other setup.

Gungnir Multibit info came from other member of SBAF ("priidik"), the story about this that somebody is trying to make tube output for Gungnir Multibit and it will be single ended. If it is succesful, then we can see it will be DIY or official upgrade.

From money/value perspective, T3 (never heard of) or Cavalli EHHA (DIY maxxed out) will be better choices if you are not too much into Jazz and vocals. The cost of them will be around 1000$. I have almost maxxed out EHHA to compare 3x times more expensive Stratus here and i can say the difference is subtle, more matter of taste.

 

The DNA Stratus uses a Russian 6N1P as a driver. As you note, the pinout is the same as the 6922, however, they are not the same. For one thing, the 6N1P uses a more powerful heater and there are other differences. It is the Russian 6N23P that corresponds to the 6922. That said, there is no reason why the 6922 won't work, although there is no guarantee that it will sound good.

 

I'm just here to second the TIII. I prefer it over the Stratus, haven't heard the Mojnir 2, in the same class as the ZDS.

 

@drfinley

That's high praise indeed.

 

I just found this highly upgraded mainline at a good deal. Just posted an hour ago.
http://www.head-fi.org/t/792580/custom-built-bottlehead-mainline-tube-amp-many-upgrades-1430

Torpedo III is really good though.

 

Swich's mainline has been up on sbaf for a while as well. He put in some really nice caps and resisters in that build, so no doubt the sale price is far less than the kit + part total.

FWIW - on the tube front, my experience and understanding from BH is that the middle tube (which functions as a voltage divider on the regulator board) - should not significantly impact the sound, so the included 12au options may not lend themselves to tube rolling in the traditional sense. (As I learned in trouble shooting my build, the amp actually operates within spec without this tube in place - it just takes the reg board out of the circuit, but the main psu board and constant current boards still function.) As for the signal tubes, I find that the stock Reflectors are better than the EH gold pins (others may disagree with this), and no one seems to favor the Sovteks over the others.

I totally love my mainline, and this one probably sounds as good or better.

 

For clarification on the first point, the mounting of the bell end of the transformer was returned to stock configuration, thereby assuaging any potential concerns over that modification (the modification was originally done due to a slight transformer hum, but it turned out to be DC offset current on the power lines in the crappy old place I was living in. The transformer mod was not needed in my new place, or anywhere with half way decent power for that matter, and was therefore reversed).

On the 2nd point, I have to 100% agree that the Mainline sounds incredibly good. I currently have a Ragnarok amp for its speaker and IEM capabilities, however the Mainline still has a more seductive, organic and smooth tone than the Ragnarok to my ears. I can give more comparisons between the two if people are interested, but in my books the Mainline wins out especially with dynamic headphones such as the HD650 and HD800.

 

Uhhh yes... have yet to hear an amp with the organic tonal response of yours, mban. It's the best I've personally heard the 800's, fed from it and Yggdrasil. Made me upset about using Gungnir Multibit with the Zana Deux for quite a while in fact. Anyway, I do believe the upgrades were worthwhile.

 

Thanks for the gracious reply and added info about your mainline mban! Transformer buzz/hum vibration from dc on the lines is a real bastard. It has been coming and going in my office recently (one of the twin towers in DTLA) and makes my F3 clone buzz like crazy at times. Other days, there is no issue at all. I'm probably going to pick up one of those emotiva dc filters since moving isn't an option.

Glad to hear there never was any issue with the amp though and I will edit my above post to avoid any confusion. It would be a lot of fun to hear your hotrodded version of rhe mainline one of these days. I will have to hope it stays within the sbaf community and makes a cameo at a meet some day. In any event, good luck with the sale!

 

You are right, i contacted Donald North yesterday and what i got for the answer:
"The input tube needs to be either the 6N1P of 6BQ7A. The 6922/ECC88/E88CC have different electrical parameters and are not a drop in substitute. In fact when I first started development of the Stratus I tried the 6922 first and found it to sound not as good as the 6N1P for this role."

 

You could roll in a 6N1P-EV. Extended life, tighter parameters.

I think I have about 8 of those running around if you want to buy a couple.

 

I've always been interested in comparisons between the two amps. I currently have a mainline, and I've always been curious about how it compares to schiit's flagship amp. Especially since it also powers speakers, it could be worth considering for a decent all-in-one solution for my audio needs. If they're exists too many compromises, I don't mind waiting and saving up for one of their up and coming speaker amps.

 

I know this is quite late, probably already snagged an amp... but thought i'd through it out as i just got one and loving it... Woo WA2...used 6922 drivers... and they can usually be had used for $8-900.