Kevin, congrats! Glad you are enjoying it so much!

Hey Fireblade,

I'm using Audio Nirvana's 15 inch driver on open baffle, and the Altec 755e also on open baffle.

You can see the speakers and a bunch of my past and present audio stuff at my personal site:

www.glowinthedarkaudio.com

For 12at7 I am using some Sylvania JAN tubes that came with my amp and which seem quite good, as well as some Valvo and Telefunken 12at7. I'll try out some e80cc in the next few days too.

The signature monos were really nice and were my second tube amp. Great sound, and great looks, but the Mini is better imo.

As for the 12ax7/au7, I haven't tried any yet but will soon. The 12ax7 is higher gain though, so if you want to lower it look at the 12au7 or one of its many variants.

I read somewhere that Steve voiced this amp around the 12at7, so I have stuck with that so far in order to have a level playing field while trying various output tubes. Plus, the 12at7 is often cheaper for good tubes like telefunkens, etc, so that is a big advantage if you want to buy a variety of input tubes to play with.

If you are curious about the gain , best to just try a 12au7 or 12ax7 and see how it sounds. It won't hurt the amp...

Input tubes often have a bigger effect on the sound than output tubes do.

The first thing anyone should try on a mini torii is the 12AU7 and the 12AT7 to find out which gain works best in their system.  Often it is the 12AU7's.  Once you settle on that you can move onto trying different output tubes.  And since you have at that point both 12AU7 and 12AT7 it would probably be a good idea to try both with each output tube as you roll.

Steve

FYI, Upscale Audio has Mullard 12AT7's for a very good price.

Fireblade,

I have owned several single ended triode and single ended pentode amps and rolled more tubes than a sane man should. Don't go nuts
rolling tubes. There will be one combination that really floats your boat with your associated equipment and when you find it...stick with it. Just MHO.

I am going to call Steve tomorrow and hopefully  order a Mini Tori as I think it will be a good match for my speakers.

I was considering the SE34 but the Mini Tori is winning...perhaps I'll get the integrated down the road.  8-)

Tube rolling: Just go slow...and don't go broke. Also, the price of a tube has a lot to do with rarity. The most expensive may not sound the best.  ;)

I have quite a few tubes and will post my subjective results when I get the amp.

I personally prefer the Mini essentially due to the input/output tube voltage regulation stages: Not a trivial enhancement IMHO.

I will definitely break-in the amp in stock configuration first.  Probably that will be enough to confirm if the original design voicing suits my tastes/needs/setup.  Then, we'll see.  I agree with both of you, tube rolling may become an obsession without convergence.

I've noticed the number of M-T units sold per month is lowest relative to the other amps, especially the Torii MKIII and now the SE34i.3.  In effect, it is a special niche, both in conception as well as flexibility.

Thanks for your good wishes, Lon.

Erik, thanks so much for your Mini w/ Klipsch feedback!  Much appreciated.

FB-If the Mini is that good with older Heresies, it should be even better with your slightly more sensitive HIII.

Ski Bum

Keeping in mind every impression put forth is subjective, the synergy with the Heresies is very near perfect.  But then again, it was also pretty attention grabbing and very musical with our La Scalas.  I don't have H IIIs, however.  I listen to very different music genres, and can listen intently to classical guitar or acoustic jazz and switch to heavy metal quite comfortably -- and with the harder stuff we go to the La Scalas. For which, based on how good the Mini Torii is, we may be investigating the higher horsepower of its bigger brother.  I'm also craving to do another amplifier project, so may end up making something on my own.  My feeling, though is that the Zen Torii is a special amp.

Hi Erik,

Thanks for the tip on the 6f6! I’ll have to pick out a pair and give them a try too. I’m still using the 12at7, but will sub in a 12au7 and several of its variants at some point in the near future. I’m primarily listening to three output tubes now; the 6bg6, the 5992 and the 350b, and each of them sound so good I could just stop here and be happy too. But tube rolling is a whole hobby unto itself!

You are certainly right about the 2a3 and 300b tubes! I do happen to like both of those tubes quite a bit, as well as the 45 and 71a, but the price to value rating is quite low there. Consider that a pair of 1953 new in box Western Electric 300bs sold on eBay last week for a cool $5000 dollars! So one single tube (admittedly the holy grail of the SET world! And possibly a very good financial investment in and of itself) cost more than a brand new Mini Torii complete with a Decware power cord, Decware interconnects and a nice variety of NOS American input and output tubes…shocking really.

In my experience at least, this little Mini Torii sounds just as good, and in many cases, quite a bit better than any of the other SET amps I have experience with. Overall, I think the output tube’s pedigree becomes less important when it is on a base as solid as this amp is. There are certainly differences in the presentation between one type or even one brand and another, but often those differences are rather subtle and neither can be said to be clearly better or worse. Always it is subjective between listeners, rooms, and other components.

In this amp, it is my feeling that it will be hard to find a compatible tube that sounds bad, and many will find that the stock 6v6 configuration is miles ahead of whatever they may have heard in the past. And we know that the price of a good set of NOS American 6v6, or 6l6, or 6bg6, or 6f6, or 6y6, or 6k6, etc is far less than even a cheap Chinese pair of 300b that may or may not sound good and may or may not last beyond its 30 day warranty.

Just my opinion of course, but I think a lot of the sound quality here has to do with the Decware output transformers, but even more than that I think it is the tube regulation. I’ve had tube regulated power supplies on an amp before, and that makes a big improvement, but what has been done here is certainly a large leap beyond that! At any rate, the wide tube rolling capability, using many tubes that I already owned, combined with a past positive experience with Decware, are the reasons I chose this amp. I’m a tube roller! And for me, this amp offers the ability to have many amps in one package, and they all sound excellent. Very, very nice.

Please keep us posted on your “third channel” Mini Torii project!

Right On! Florida Boy.  Welcome to the loooong waiting list

"It's a tubed erector set for audiophools with OCD.  8-)"

Yes! But this one is actually affordable to roll tubes in...more audio and less fool!

Yes, I do still have the MHDT DAC. I love it! Four or five years now of almost daily use.

But, I'll admit I'm thinking a lot about the new DAC from Eastern Electric. Now I can sell a spare amp or two to finance one.

Kevin: indeed, circuit design has a substantial, of not critical influence on the voice of a component.  I have said so often in thempast that, IMO, the best, most expensive capacitor exotica will not make an already
Compromised design better, nor will more expensive valves.  What the mini torii also illustrates is that OPTs the size of arc welding machines are not required for outstanding and comprehensive frequency response -- though they do need to be suitable for the load to which they're connected.

I admit those 350Bs must make a very nice visual statement in addition to sounding great.  I have spent not only a bit more but hugely more on a pairmof 2a3s or 300bs (as I'm sure you guys have seen, as well) for the amps I've made, so the cost of your 350bs is a bargain in comparison!

+1

For the most part I've learned to trust Steve to get the bedrock just right. After that I just tailor to my room and tastes. (And though I've learned to trust a number of ears here, my first allegiance are to my own left and right!) A winning formula: Steve + my personal experience=sonic joy!

That's about right. Not going to mess with a good thing.

Nice pic! When I first looked at the Mini my initial thought was 'Swiss Army knife'.

I am a recovering tube rolling addict...this amp is not going to help but the cost of a fix will be a lot less. I will burn it in with the stock tubes though.  

Do you find the amp to sound neutral, warm, cool etc.