spritzer

I was supposed to get one in February but last I heard nothing had arrived. It's been confirmed by Sennheiser that the output impedance is 43ohm but they are very tight lipped on the circuit inside. One of the R&D guys was here in the spring as said the window on top was for people like me, to save me the trouble of opening it up.

I think that rig is the old 57 setup from the old Huntington factory as it was all shipped to Germany when the production was moved. The panel on it is a ESL63 but the setup is the same as for the 57 with that flat oven at the end of the track to heat set the mylar.

I bet you can use Comcast to access a place where it is available on demand...

Pixie dust is as good an explanation as anything else but I think there are two reasons for this, how the ring radiator behaves and that this is Sennheiser. The ring radiator has some pretty interesting properties and is clearly undamped in the HD800 so it must need some electrical damping to make it behave and become more linear. I haven't looked into speaker designs using these but they might be doing something similar there. They are certainly known for their high HF response so some compensation might be needed to keep them inline. As for the latter lets bring up the HE60 and HE90. The drivers in both are kissing cousins aside from the materials used. Same basic principles, conductive paint on non conductive stators and the same diaphragm material. Assembly is also very similar though the poly-whatever Senn used on the HE60 meant it could all be integrated into 4 pieces. Anybody who has listened to these cousins knows how vastly different they sound and more importantly, just how different their amp requirements are. The HE60 needs power and low output impedance but the HE90 doesn't. In fact if sounds more placed with higher output impedance. Transducer size is a factor here as electrostatics are more efficient the larger they are but Sennheiser clearly tampered with the way the drivers behave. The HD600/650 is a similar case but here the drivers are the same, the baffle is different. While low output impedance is a good thing there are exceptions that prove the rule. What I need is a two to 4 gang linear 100R pot to test on the fly but these are not easy to find.

Not the first one to have the bridge issue. It's fixed on the new boards...

Do you have a GS-X or something similar there Tyll? It's an interesting comparison with the L-2 once you match up the output impedance.

That TOCO's just looks like a cheap ceramic pot so color me skeptical. That's what Craig says, he even says only stupid people who don't know what they are doing use 4 gang's...

Fully vented top and bottom is not a bad idea. Not needed here because we never get above 20°C... ever.

Ahhh PRP's, where the reject pile almost equals the useable units. That's why I use CMF60's instead.

Probably on demand... well sort of...

It is quite good isn't it...

I thought I recognized that one. but had to scratch my head quite a bit..

If we were ever to think about how much money we pour into this stuff then we'd be sure to take up substance abuse... as it is much cheaper.

Hmmm ESP950 is out of stock... crap.....

Yeah... that is overkill gone wrong.

Fake it till you make it is my line...

As good as the HD800 is it pales next to an electrostatic so yeah, the only sensible option.

There is nothing that would make the amp sound better over time. Broken is broken so just do a simple loop through test on the computer and see what is going on. I also don't see the benefits of running higher rail voltages like that. The amp was designed for a fixed point so I'd stick to it.

I suspect something is broken for it to sound this way.

I really need to chat with him soon to make fun of the utter clusterfuck that was the new album release....

I'd say they sound similar as in they sound "correct" what ever that means. The designs seems different but take an abstract view and they are quite similar, the goal is certainly the same one by giving the amplifying device(s) the resources really needed. The L-2 is far from a bog standard tube amp, there is a lot of sand in there and though the signal just passes through the tube and transformers. Same can be said about the Dynalo, the amp itself is very simple but the number of parts comes from the parallel output stage and CCS loading. I'm also matching the output impedance of the amps and that makes them more similar or rather removes one of the biggest obstacles in amp comparisons. It's SN: 8329 so probably about 2-3 years old by now. Stock there is a leading edge to their sound. Not Grado level of bright but push them with the wrong material and they will bite. Granted this is not as annoying as the edge on the SR-009 which makes them unusable to me but it's certainly there and exacerbated by lesser amps which can't give enough instantaneous power.

No problem on my end. Not tested just yet but I should have the final parts this week.

I just fired up the Dynalo (aka GS-1) again and with a 42ohm impedance adapter is does sound very similar to the L-2 except there is more top end presence, the soundstage is huge and hello bass! Remove the adapter and it is a very different story...

The KGSSHV PSU will work for the Megatron. The universal was just that but with an extra C- supply for the BATE, ESX etc. and a delay line for the tube heaters. I'll use the BH supply so just above 400V. Much smaller and stuff I already have assembled... For the Dynahi the S22 will do just fine but don't skimp on the heatsinks.

Just about perfect, just missing "til (to)" at the front. Direct translation would be "to happiness with your birthday".