Torpedo

That would be great. If Luvdunhill can transfer the cancelled order to Carlos, then he'd be in for 2 additional S22 kits, I suppose with the upgraded Muse caps and big heat sinks too. If he's in, then having carlosgp with Casino access would be good too. You'll receive the PM with Rodrigo's address as soon as I finish this.

Would it be possible to add another member to the group build this late? A friend of the Spanish team, also a Headcase member (carlosgp) but as Hitori and Picaudio not very participative, knows about the build and is very interested. He would be in for 4 Dynafet boards with needed transistors and heat sinks, and 2 S22 power supply kits. I don't know if he would build it himself or would get Picaudio to build his too. I think the big heatsinks, Muse caps, and blue leds are OK for me too. Regarding the address, the kits and boards should go to 15007 A Coru

Spanish team is in for 2 S22 kits each, so 6 kits in total. They can be sent to Picaudio since he's building my unit, and he'd send the 2 remaining kits to Hitori. Not sure about the heat sinks, I think having to design the box to provide dissipation for two PS boards can add some complication. Aren't there any on board sinks which could work? OTOH my B22 is using a single S22 to feed 3 signal boards, uses on board heat sinks and not a single problem so far, not myself nor any previous owner that I know. In fact I don't think it even gets worryingly hot. Would driving 2 Dynafet boards be that much more stressing for the S22 than driving 3 B22 boards?

Very nice, did you DIY or got it from anywhere? I think I might try one of those on some records.

Omnivorous. Widening horizons as far as I read about performers I didn't know, or hear something appealing. If into anything reminiscing of a phase, perhaps I'm into a female singers one which includes even opera, but this is lasting several years, so probably more than a phase it's a personal bias.

IMO it'd be great having lower gain or a selectable one. For most cans, considering a 2-3V output source, 11x is too high, even 8x is very much considering my experience with the Beta22. Any idea what would be the lowest gain the circuit can take without becoming unstable?

Sorry for you Rodrigo

I can't speak for Hitori nor Rodrigo, but I think that getting the S22 boards and parts at $67 is a good deal, and if the kits come assembled it will save Rodrigo some additional work. For me it's fine. If they agree they'll say soon. IMHO it'd be good the kits came with the onboard heat sinks, the ones required to dissipate the power two Dynafet boards ask from one S22. I suppose that'd be the same for everyone. In the same way I guess we all be using 30V output trannies. Icarium, thanks for updating the spread sheet with the transistors needed.

Let's see if using the code trick it displays as typed: RbL At= -------------------------- ( RbL

OK then, but please add the transistors to populate the 12 Dynafet boards and also the 6 Sigma boards with their parts for the Spanish gang. I think that getting the S22 boards in kit form if it's flexible enough to let you choose your trannies can be a good thing. At 67$ doesn't sound very expensive.

We also would like 2 Sigma boards each, the transistors for the Dynafet and the parts to populate the S22, unless Picaudio states otherwise.

I've checked it. Did Hitori contact you and said he wanted 6 boards instead of 4? Maybe he wants some spares hahahaha.

Happy Bday, enjoy a lot

You said that covering the TV screen changes sound. Does the soundstage going to the right improve and get more centered when you do so? If stage shifts to center when covering the screen, but it's not dead center with a mono recording, then try using thicker cloth to cover the screen, it might work perfectly for "serious listening". Other cause for that could be the low frequency sounds having more room and some reverb when getting into the next room through the door. Maybe adding a very thick curtain to "close the door" is of some help.

I won't make things more complicated for Picaudio building my Dynafet, however the trannies can become handy when using a SE source to drive balanced headphones.

Are you planning to use the Sowters for the PS and the balanced to SE conversion or just for the second? I can't say myself, I need Picaudio or Hitori to show up. On the other hand it depends on the savings and what Sowter says about sending some trannies to Spain directly, maybe it doesn't make it any more expensive for you, so it saves us the risk of paying custom duties for an European product and the sure cost of shipping from US. Trannies are heavy

Precisely that's one of the reasons I'm not very sure about trying damping just parts of the driver. I'm not sure this driver produces more bass or treble in some areas of its membrane, I imagine it behaving as a piston moving back and forth, floating into the field created by the two sandwiched magnets. So if I damp its vibration only in some zones, maybe I'm creating resonating nodes and breaking points on the membrane, which could affect negatively its performance. I see damping it just as a way to limiting its backwards motion to increase its stiffness, so it can respond faster to the changing signal and also has less excursion (hence less delivery) on low frequencies. This is what I think I'm hearing now, a faster driver, having less bass output so the treble shows off better. I think I didn't get as a good result with the single 6mm felt layer because I didn't use any glue or tape to attach it to the back of the driver. Just adding 3 small pieces of tape to hold the felt in place against the driver, has provided better damping still in that good point where dynamic impact, frequency distribution and midrange clarity meet a quite good balance. Maybe I can bring out the upper treble a bit more, but then I'd be very close to make them sibilant or suffocating them dynamically. So perhaps before trying more damping or reflex dots, I'd better see what happens using bigger circumaural pads when I get them.

Oh no, not more options please hahaha I think I'm just going to try an additional layer of the medium density, and then using the phones for a while if this works well. Then if I still feel it can be pushed beyond, I might try a smaller disc of the high density felt. The damn thing is really dense.

Well, I think I've got quite a decent result by using the 6mm medium density felt in a single disc which I keep held against the driver using just 3 small pieces of tape at 120

Well, not a big problem, just need to change wires

An update. The high density felt is too high density, it damps the driver too much and while the treble shows off better, the midrange is still good and the bass is less present, I get dead dynamics. All the fun factor and jump into the music character I love in the T30s is gone Looks like I was very lucky on the first trial with the medium density felt using a thick 6mm layer, which provided the right amount of damping. I'm afraid that I can't get much better than yesterday just damping the drivers and the enclosure. Time to try other scheme. I hope the threads for the screws holding the drivers can stand such back and forth.

Does it have any selector to let the signal out to be only SE or balanced, or can you use both outputs at the same time? If you can use both outs at the same time the only "problem" with such circuit could be that the hot out in the balanced output, and the SE active would be "seeing" the input impedance of the two preamps/integrated/headamps you were using in parallel, while the cold rail of the XLR output would see just the balanced pre/amp input impedance. While this is quite a minor concern, it could have some audible consequences. To avoid this it would be advisable to use only either the SE or XLR outs and having only one pre/amp connected to the chosen one.

Yesterday night I listened to a couple of CDs damped just with the one layer of 6mm thick medium density felt. The sound is damn good timbre wise, voices really sound to die for, bass is deep, still excessive but damn fast and very resolving kind of "that must be a Fender Jazz bass and that other one a Fender Precision" completely separated from the kick drum and all other bass sources including synthetic ones. However the treble still lacks some shimmer and "air". Considering previous experience with other cans like Grados using flats, bowls, etc and the L3000 adding spacers under the pads, I'm not sure at all that placing the drivers further from the ears just brings out more treble. For sure it will do, but it might spoil the spot on timbre in the midrange. I tried other supra-aural thick pads I have around over the stock modified ones and midrange went away, not a good result, however with circumaurals which left the driver closer to the ear, it could be a spot on change. I'm going to try more aggressive damping with the high density felt closer to the driver and using the medium density one for the enclosure. We'll see, perhaps I lose some deep bass (just having less won't harm) but if midrange stays as is and I get more extended, shimmery and airy treble, I'll be done for damping. The T30 are my first and only pair of orthos. I'm liking them enough to try more, but not sure what. Maybe the T50V2 (Nad, etc) are too bassy for my taste, so I'd be better served with the newer T50RP, or I just keep an eye wide open for T50V1 or YH-1000 Kabeer, thanks for your observation about the reflex dots. I don't think I'd be using them so far. IMO reflecting the backwave back to the driver, which is a membrane completely separating the back from the front side, would cause more cancellations and trouble than benefits, maybe that explains why you find them congesting the sound. My intuition says that having a bit more damping on the driver by using more dense felt, can make it even faster and perhaps decreasing a bit the total amount of bass. If this works as expected, I'll be quite happy

Hi Kabeer, Thanks for your reply. For resonances and backwave control I think the thick felt is working irreproachably, I haven't noticed any of the minor resonances I was able to hear before, and the bass is as tight, fast and clean as I could wish. I hate to recognize it, but I'd say it's more proper bass than PS-1's quality wise, mostly for the unbelievable resolution the T30s have there. However I could try the high density felt closer to the driver and adding a second layer to fill completely the back chamber as it is now with the thick disc. I'm waiting to get some big pads to get the same effect than I managed when trying the CD3000's pads. I know it works wonders to bring out the treble and providing stage depth and "air". However the closer I can get to that just by damping the driver properly, the better will be the final result IMO. It's just that I'd like to save as many trials dismounting the driver as possible to avoid damaging the enclosure.

Blackmore, I find difficult to know if they're using every triode into the ECC82 for the output, so every tube can deal with both rails of the balanced path, or whether they're using just one triode and only one rail is "tubed". The late makes little sense, but who knows. I'm not sure at this moment if the SE outputs go tubed or not. Are they? In this case the whole balanced path could be not tubed and being fed by those 4 discrete transistors which we can see in your last pic, which are the same showed in the first and second.