ECP Torpedo III [indexed in first post]

Do you have a Yggdrasil? Which tubes are you using? Which amp did use use with the Yggdrasil and HD650 previously?

 

Yeah i have an Yggdrasil, i'm using usb input with a LPS spliced in. The tubes are 12AZ7's nos from service master not sure what they are, i think they might be GE tubes, i can take some pics of the tubes perhaps someone can identify them. Previously i used an Audio-gd Phoenix which is still think is a good amp but it is being outclassed by the T3 even as i hear it now.

 

I should put in the GE 12az7 tubes I have to confirm but my memory is that the tube has lots of punch and attack. We all enjoyed that family at the meet, ranking it pretty high, but maybe brimar, mullard, valvo tubes might be just a bit more laid back if that's what you're after. I still think the brimar tubes are amazing for that while still being detailed and open sounding. Mullards probably give up some detail and add more warmth, but I'll let others chime in.

 

LPS spliced in, eh? Wouldn't mind some further details on this offline.... But if they're GE, then I'm surprised at what you're describing, because your chain is almost identical to our T3 tubefest chain which was:

Tidal FLAC -> Gungnir Multibit (close enough to Yggdrasil) via USB -> T3 -> @Bill-P modded HD650.

Yggdrasil Gen3 USB should, theoretically, even be an advantage for you. I felt the GE 12AZ7 was quite different than the Amperex version which was a winner in the attack transient category (and in most other categories as well). My recollection of the GE was more laid back, actually. But I agree with @brencho that there are others out there with even more reserved character. And, quite honestly, I think the Audio-GD stuff I've heard is pretty meh. Lacking in resolution, precision, and imaging. The T3 is likely superior and you may just need some time to adapt to a new reference. Transitioning from a smoothed-over tubey OTL amp might not be an all too different scenario.

 

I am not caught up in the last few pages of the thread BUT -- FWIW PCX is sold out of the Amstrans 100k resistors I was ready to give them a try with their sale pricing. The lean signature of the mundorf alu oil caps I can definitely relate to; maybe it is a trade off for the clarity but they are not exactly deficient by any means.

 

I ran into that issue with PcX, as well.. so I ordered them through acoustic-dimension.com. The Amtrans are actually a little cheaper there vs PcX (even with the 20% PcX discount). At worst with freight factored in (PcX shipping cost for a few resistors sent to the states seems a little high, IMO), it's a wash.

 

I would like to change the output transistors to a warm transistor that is higher in 2nd order harmonics, with minimal odd order harmonics or other noise. A tube like transistor.

I am not sure which MOSFET or BJT will accomplish this or if it exists. I heard some JFET distorts like a tube but I am not sure if JFET can be used in this circuit. I would need guidance on this.

 

JMHO, but you should probably drop back to some Solen capacitors if the dynamics are the thing that's bothering you. I agree with Dsavitsk that there is potential in changing output transistors. However, after years of fiddling with the very same thing in the Millett Hybrid MAX and MOSFET-MAX, the potential changes may just be in the margins. Combine that with the effort of changing out heat sink mountings and it could quickly result in diminishing returns. I think if someone is still interested in tweaking the amp and discovering new improvements beyond the tubes and caps, it could be worthwhile.

Steinchen documented a number of output transistors for the Diamond Buffer boards he designed for the old revMH Millett Hybrid (Drew Dunn's and Nate Maher's 1st iteration after Pete Millett's original). "Note 2" on the webpage link below details the changes that you might expect by rolling output transistors in a zero-feedback design. However, I have no idea (neither does Doug, I think) whether this is comparable in the T3. None of the transistors listed have the voltage requirements for the T3, either, so don't go thinking you can put a set of these in the T3 - it's just an example of what transistor changes might accomplish. The primary quality of the Millett Hybrid was that it was a tube amp that ran on 24VDC throughout the circuit, so not parts-compatible, at all.
http://www.diamondstar.de/dDB_partslist.html

I'm still thinking something's wrong with your amp, though, Jun. Your comparisons with a Bottlehead throw that in doubt - so do some of the other recent comments in this thread. The photos you sent me didn't really reveal any obvious issues. So, it's still a bit puzzling. Dynamics and clarity are desired in an amp, not something to avoid. In my mind, if greater dynamics are bothering you, they must be accompanied by greater distortion. That was Dsavitsk's conclusion right away - that you have higher odd-order distortion than normal. What's causing it - assuming it's not your direct comparison with a Bottlehead - will require more detailed troubleshooting, perhaps.

The Solens actually add a bit of "fog" to the amplifier. At the same time, the highs are a bit recessed and the bass is fuzzied up a bit. All those qualities combine to lend a bit of softer warmth to the sound signature. I have several built T3's right now, both with Solens and Mundorfs, so the comparison is easy. The Solens sound great. That is, until you switch to a T3 with the Mundorfs. The greater transparency and detail is immediately apparent and the sound is superior. The best way to describe the difference is that the Mundorfs don't seem to be there. It's as if there are no caps in the signal path at all. In my mind, that makes the tradeoff worth every bit of the cost/trouble, but the Solens would be perfectly adequate for someone who hasn't heard the difference. The Solens are definitely superior to the Epcos box caps, which in turn were superior to the Wimas and Roedersteins that I also rolled into T3 versions in the past.

If anything, the new output CCS's are another game-changer. One of the two things they seem to do may address exactly what some of you have complained about: strengthening the bass. "Lean" might be interpreted as a bit less bass emphasis and lack of focus. That's exactly what the output CCS's address - that, and an overall increase in micro-detail. As mentioned earlier, they also make the amp run hotter. We'll need Dsavitsk to weigh in on exactly what they are doing. My conclusion on both the sound quality and physical heat effect may just be a coincidence, but they act just as if you've turned up the bias on a Class A circuit: more heat, but greater bass and overall detail.

I received all of the new CCS boards yesterday. So, hopefully they will become available in the next week or so. They are more complicated than the tube CCS's and require 4 for each amp. Plus, there is ECP Audio IP (intellectual property) design and development involved, too, I still have some of the pricing details to work out with Doug, but that will happen this next week. Hopefully, the sticker shock won't be too bad, considering the benefit. I've installed them on 3 Torpedoes so far (all with Mundorfs) and would consider them a required upgrade, but that's just me.

 

Looking forward to buy the output CCS boards, and thank you for the continous development of the T3 amp Dough and TomB

 

@TomB
I really want to know. Could I just trade in my T3 for one of your T3 with output CCS, Mundorf and Cinamags. I can pay the difference in what you would charge for labor and the CCS boards.

Once you have the amp in your hands you could probably figure out what's causing the distort easier than any pictures I send you.

The distortion is probably minor, but it's just enough where the dynamics start to annoy instead of help. I am still amazed by the amp but I just kept thinking it could be a touch softer and it would be perfect. Keep in mind I upgraded from an overly tubey, warm and soft sounding OTL tube amp the bottlehead crack.

 

Well right now i'm gonna let the caps burn in, been doing some burnin and it seems to be mellowing out a bit so i think it's wise to wait with buying all kinds of different tubes.

Well the tubes are fairly new, the caps are new and so are the resistors and PT. I think there is just too much going on at the same time and i was just hasty with my judgement, i confess i wasn't in the best of moods as well, that probably affected things too. Like i said above i will give this some time and not do any further changes and form an opinion over the next couple of weeks.

About Audio-gd, the thing i noticed with my Phoenix is that if the bias is off a bit it starts to sound like shit. Once i dialed that in it really improved but you have to be careful when you bias it as well. Wait till it's reached it's normal running temp etc and then dial it in. Perhaps those amp's are a bit thermally unstable, i noticed with the Phoenix that if it got warmer then the temp i biased it at it started to sound a bit muddy and veiled.

The splicing thing it's quite simple, a few years ago i wanted an upgraded psu for my V-link 192. So i bought one similar to this:


It has usb B male and female plugs on either ends.

@TomB Your description of the output CSS board's has me intrigued, looking forwards to impressions on that

 

Things are definately sounding better now, i don't know what burned in but i like it. Wouldn't want the Solens back now but it's kind of a bitch to a b that

 

I been spending a lot of time listening to the T3 at work and i have been trying to figure out what i've been hearing. I like the bass and highs of this amp a lot, and something in the mids presentation is different when compared with my other amps. It is most prominent listening with the HD800S and HD650. Not as much in the HD600. I know the former cans are laid back, but maybe my ears are colored. i dont remember my 650's sounding like that laid back with a transparent dynalo when i had one.

I feel like i have to turn up the volume higher to hear anything clearly in the centerstage (usually the vocals). Does anyone find the presentation of the mids to sound recessed and/or even slightly out of phase when 650s or 800s?

Is this a personality of the stock tubes? What other tubes make the mids more prominent?

 

That's odd. Have you triple checked that there is not a component out of place? Can you run it through RMAA to see if there is a phase issue?

 

I don't have a measurement setup, and i used some test tracks to determine what i'm hearing. I don't mean out-of -phase in a extreme way either because out-of-phase track definitely sounds out of phase. These are very subtle differences like everything else in hifi land.

The mids seem to come from no where/inside my head (the voice doesnt exactly sound like it's in "the center between my two speakers") relative to what i'm used to and mids i would describe as recessed compared to the highs and lows.

 

It doesn't sound like anything I have heard. But the only real ways to figure out what is going on is to either compare it to another one, or to take some measurements.

 

There are a couple things that can cause this, related to the tubes:

1. The tubes themselves have a mids-recession. Try another pair.
2. If the tubes are not perfectly matched, and in particular - if one tube is substantially weaker than the other - you may get the situation you describe. Mids are the most directional frequencies in a stereo signal. If there is poor matching between left and right tube output, you may sense that the mids are not centered or out of phase. This can be confusing, because stronger peak signals are often focused on one channel or the other, to enhance the stereo experience. This may lead you to think things are normal, but the mids are "not quite right," for some reason.

Try switching the tubes from one channel to the other and see if the off-center, non-localized mids change direction.

Another thing that can cause this is reversing the channels. We've apologized for this before, but the RCA jacks are keyed on the color of the RCA jacks, not the "L" and "R" etched on the back plate. If you connected your patch cords using the "L" and "R," the channels will be reversed. This can cause confusion if you've listened to the music before (or tests). In extreme cases, it can run counter to the producer's fundamental bias in the music and not sound natural at all.

Or, there's something wrong with your amp.

 

While I was at it, I thought I'd post some pics of my personal Torpedo III:

 

Maybe a damaged cable, or a solder bridge on the inputs? Vocals are typically center panned, such that you can actually produce a crappy "instrumental" track by subtracting the L channel from R or vice versa. Definitely check if it's playing proper stereo.

 

To clarify, im not talking about channel imbalance L or R. The presentation of the image is just not in front of me, it is perfectly centered inside my head rather than in front of my face. I describe that feeling like listening to the out of phase track, but of course no where near that extreme.

Motivation to go to a meet and hear how other T3's sound. I am leaning towards a tube personality clash. I did notice the silk screening issue (left and right channel test didn't pass on the first go).

Like Grado/LCD instead of HD800 in the midrange focus only. i jacked this from Marv's headstage thread hehe


I like the red anodize