There's some information here in the designer's notes to the Torii Mk II:

https://www.decware.com/paper68.htm#TUBE%20RECTIFICATION

May not answer all your questions, but it might help.

I've been thinking of upgrading my current system, Adcom GFA-555 amp, Adcom GFP-555 pre-amp and KEF Model 103/3 (4ohm) speakers with KEF Cube, for a few years.  I have the matching Adcom CD player and Tuner.  Anyways, I really like the system (had it for 25 years), but have the upgrade bug!  I have been looking at the SE34I.2 and waiting for details on the SE34i.3.

My question is - I like my KEF speakers (92db sensitivity) and would like to keep them for now - but the KEF cube plugs into signal processor inputs on the Adcom pre-amp, using 2 rights & 2 lefts.  If I were to purchase the SE34I.x would it still be possible to use the KEF cube with the KEF speakers?

Per a Audio Ideas review from back in 1987:

"The KEF 103/3 speakers are a 3 way system with  a dome tweeter and 6" midrange on the front and a 8" woofer facing down - all on a dedicated stand.  The KEF cube eliminates crossover inefficiency losses allowing for extended bass response.  The normal speaker measurements are 50hz - 20kHz.  The KEF cube allows you to vary the frequency range below 160Hz by about 3 DB." (though their tests showed a closer to 6 DB with the cube extented button activated).

Anyone on the forum have experience with these KEF speakers and KEF cube using Decware amps?

Thanks        

The crossovers in the KEF might rob the amp of a lot of power. The 92 decibel rating might not mean that much after the crossovers take their toll.

Is there any possibility that you would ever consider trying something with higher efficiency?

I can endorse the MG944's wholeheartedly.  That Integrated would drive them to insane levels of volume, and lead to a completely life-like musical reproduction.

Stone -

I agree with you.  I keep checking the "New" link on the main menu and the "Hi-Res" link on the SE34i.2 product page thinking Steve has placed a picture of the SE34i.3 there.

markv wrote on 02/06/12 at 02:21:28:


Either one would be a solid choice!

Lin
H-B Type 1 owner

Interesting! Not what I was expecting. Looks beautiful. Thanks!

The Two power supplies in the SE34I.2 were heavy overkill.  Remember those were designed for the original SE34I that had four output tubes rather than two.

Right now, we're still at the same 40 mills per tube as before, so both channels draw 80 mills.  The current power supply is 150 mills.

So to answer your question, no, it is no longer dual mono.  

I'm in the final chapter of the voicing on it, and comparing lucid mode with one built as a classic SET just like our Zen Amp (SE84C+).  It's looking like getting lucid mode as good as it was on the Taboo may take another year or even two (like it did for the Taboo).  Triode vs. Pentode is just too much change to have the same results.  Don't get me wrong, it's impressive in it's current state, but in a serious shoot out between the two designs,  The classic Decware SET may actually have the edge in the imaging department since it's more accurately rendering the intent of the recordings.  Given that and the fact that the amp could now be bridged mono I'm likely going to abandon the unbridgeable lucid mode on this design.  After all, we still make the Taboo.

The meters are to show the bias of each output tube.  This lets you know a few things:

1) When the amp is ready to play music after powering on.
2) What the bias is for each tube
3) If the tubes match and if not, and how far off are they
4) Visual clipping indicator to make it easy to determine max power levels
5) Ongoing tube wear indicators
6) Tube failure (shorted) indicator

But mainly to let you see at a glance how close your tubes are matching and how close your amp is to max power.

...no the tubes do not have to match, especially if you have the amp configured with dual volume controls... but matched tubes mean that each channel will clip at the same point - not one side sooner than the other... and closely matched tubes preserve pristine imaging.


Steve

Yes, but so far just one rectifier sighted.

Beautiful design, indeed.  Ok, it's not going to be a Lucid Mode-capable design, but I wonder how does it compare to the SE34i.2+ it's replacing in overall performance?  Any comparisons made already?  

If they sound better than the SE34i.2+, these are going to make killer triode monoblocks!

Steve -

What are the other configurations you are planning for this amp and for how much?  Also, will you offer a stock set of tubes as an option?  Finally, what does this amp look like with the contemporary walnut wood base - pics

Well, while they may dry up for me by becoming unavailable in quantity but I can't image that they would ever become unavailable in singles from places like ebay.  That said, in a worse case scenario I would likely replace the VR tube with a neon lamp.

I suppose you're correct Steve.....we should be able to find them on ebay etc.... (voltage regulation tubes/down the road purchase). They last forever too. It should not be much of an issue.  NO neon! Go with a black light and lets bring back the Posters too!  ;D

The release is here!  Sweet!  She is a beauty (that Rachael)!

Rachael!  I like it!  This could be love! .....Those sexy meter's.....what a vixen....hubba hubba........

Ms. Rachael?  I do believe you're trying to seduce me?!

Steve -

Add to Cart is not working for this amp - can't order.

Add to Cart may have been repaired. At least it's working for me now, I played around with it and it functioned as expected (unfortunately I'm not buying an amp, but tested the buttons).

Before this thing was introduced I was leaning towards a set of SE84ZSM monoblocks but now I am not so sure.

I would not be comfortable with using this "Rachel" as a power amp wide open with no volume control. Right now my Mini Torii connected to the CSP2+. When the volume on the MINI is wide open I hear some noise that is not audible when the volume controls are lower; thus the ability to ride the gain between preamp and amp is necessary not only for greater versatility but to avoid any noise.

Other than 6 watts what are the differences in sound/performance between the Rachel and the Zen monoblocks?

I'm a little disappointed with no 12au7 as I have a bunch of nice E80CC here that made my mini-Torii shine. Oh well.

I might consider using amp version with zodiac gold still.

You can't lose really. If it were me, I'd go with the Integrated, simply because I think the "noise" thing is a non-issue and I know how great this machine can sound. 6 watts triode? Wow.

But the Mini may serve your purposes as well, and your order is already in the pipeline. The wait is going to be agonizing. Best of luck, and I know you'll keep us posted of how it sounds when your system starts to come together.

The color rendition on your monitor might differ from mine. I see them as gold.

Quote:


Well done, Lon... you're basically correct.  The simple answer to this no doubt popular question is going to be that Rachael is slightly warmer with a boat load more power.

Yes, Lon, I sure will be counting on you guys to assist me further  through the fine-tunning/break-in phase, thanks.

Regarding the Mini's voltage regulation feature, I want to go along with Steve on that one.  He was pretty emphatic about it, for some reason.  I also don't enjoy good/stable power supply through the mains, locally.

My only personal reference in tube amplification has been my ex VTL 225 Deluxe monoblocks (typical push-pull), using EL34 tubes.  Mid and highs were gorgeous.  Bass, although strong, was not tight enough, to my taste.

I don't have references for a SET nor a SEP, other than what's in the literature, and that's why I was originally inclined for the integrated.  So eventually I chose the Mini based on specs and user's descriptions, but most of all by Steve's suggestion.  Iwonder if his advice would have been the same today?

In any event, as you say, I can't go wrong with either, and the Mini's features and specs are very complete.

According to my calculations, my Mini Torii order's lead time is exactly 8 weeks today, out of the original 12!











 

Hi Steve!  Is this Mini Torii's hyper-gain characteristic, which is aimed at assisting weak signal sources, like ipods, a drawback for someone normally using 2 to 2.25 Vs ouput sources?  I mean, having only half of the volume dial to adjust may become too sensitive maybe?

Can we assume the same amp silence on 94 dBs speakers with a CD player on a Mini Torii if volume is set within the first dial half (i.e., before clipping)?  Thanks!

Hi Steve,

I am truly glad that you have decided to use the ECC88 family of tubes for the new amp. I play with them alot and part of the fun of owning a tube amp is the tube rolling.

That PLUS the Hazen Grid mod for EL34s makes this a killer amp in the sonics department for the mid-range.

HINT HINT : I now know many months in advance what my 2012 year-end bonus will be used for!  ;)

BTW, I noticed that you have offered the Shuguang Treasures as an upgrade option. I am sure that you would have experimented with various types of EL34s during the design phase.

I hope that you can share your tube-rolling experience on the various EL34s which you have tried whilst designing this new amp.

Cheers!

Soth

The switch behind the volume control is probably a bias switch.

I just realized my earlier question is almost impossible to answer, I apologize.  

First of all, pentodes (beam) and triode tubes can sound different by their own nature/design.  I understand there's no 'better than' here, as it depends on circuit and transformer design.  Also, how they sound is a very subjective preference.

Purists would hold that a DH-SET with a (directly heated) natural Triode tube and absolutely no feedback (pure class A), with the simplest circuit possible and huge transformers, are the ultimate in sound.   These are also very expensive, if done right!

On the other hand, there are many fans of PP topologies using Triode output tubes like the EL34.  There are also the 300b, 2A3, 800 tube SET proponents, etc.  It goes to show the essentially subjective nature of the beast.

I guess the only ones able to actually answer my original question is Steve and Co., right now.  I'm really sold on the Mini Torii, is just that every now and then I get these doubts.  I guess I'll have to try them both  ::)

In any event, anybody with actual owning experience with Decware's SE34i and SE84 amps may have a better clue and may want to share their opinions.  Thanks!