spritzer

Some news, the new prototype mini boards have shown up. Spent a couple of hours stuffing the amp boards but we'll see what happens when I turn them on... Don't know how we missed the huge mounting holes on the PSU board... The new SMD fet is just a bit too fucking tiny though.

Only the input fets need to be matched, the rest just needs to be from the same class.

Happy Birthday little one...

We should get him to model the new Kings Sound headphones...

Well my T2 transformers would beg to differ... I've never had imbalance issues with the 100 or so Alpha pots I've used but this could be one of the broken ones. A few of the pots I got in my first shipment had some sections reversed so they wouldn't work correctly. If you can feel a notch when turning it then it would be one of these. I thought I had found them all and returned them to Alpha but I could have missed one. Regardless, just PM me your address and I'll send you a new pot. We can't have an imbalanced amp.

It's easy to bend the metal arcs to get the perfect fit.

Yeah, sounds like a blown transistor.

People are free to do group buys but I'm only buying boards for my own testing.

I was using steel screws and the heavy duty insulation. This is only at 250V but the K216's are a pain to fit with those insulation washers so that's probably why it shorted out. There was a nice melted puddle of insulation at the top of the K216 tab... The 3675 fail was at the PCB so sloppy soldering on my part or rather, sloppy desoldering. Never work on HV when you are tired...

I've ordered some prototype PCB's of the onboard and PSU to try out. The offboard has become a massive headache to modernize so I have to either do it from scratch or go to a 3 layer board...

I have a lot of reservations about the Total Dac to say the least. Now if Lavry could just update the 2002...

The MSB DAC IV and the Analog dac can both do DSD. They refuse to upgrade the DAC III's even though mine has pretty much the same USB interface as the IV. Fuckers...

Hey, it's a real problem...

It's worth a shot...

I've seen spots on the utterly fubar Stax sets but that's about it. No large levels of corrosion and it wouldn't have any effect on the sound of the drivers. The drivers could be completely covered such as ML does.

I already did the diode tests but said fuck it and replaced everything in the amp. It's not like I don't have a few 3675's to waste. Still didn't fix the issue though. Might be a blown resistor but how unlikely would that be with no visible marks... As it stands now all the sand except the servo has been replaced but no change. One thing that worries me is that the front end CCS doesn't light up as it should. All the active parts are new so it should be fine but that might be a cause. Another could be the servo but it appears to be working just fine. When the amp first turns on the main CCS's light up but are turned off half a second later as the servo kicks in.

Up or down doesn't matter.

So I've been busy. Changed all the free standing 2SA1486's and 2SC3675's, the 10K pots and the 3675's that are in the batteries but located on the sinks. I know the LED's work so it has to be the 2SK216's in the front end CCS. Just has to be as everything else has been changed. Might do the 2SA1486's in the front end while I have the heatsink off. The main CCS behave the same way on the good channel with the batteries not connected so they should be ok.

That's pretty much what happens to mine. I get a small change at one point but it's from around 802V down to 790V.

Do you remember which parts you took out?

Have you tried just replacing everything? This is clearly a damaged part somewhere in my case as the amp did work before things started to short out. I'll first try to rebuild the batteries and then work my way outwards.

Anybody have a problem where the batteries are stuck at 797-820V (max adjustment range)? Mine is acting up as before and it started after one of the K216's in the front end CCS had shorted through the insulation and a 3675 in the main CCS had also shorted. Changed all the offending transistors, the J79's and the 100V zeners plus the K216's in that stage. I also swapped out the fet and C3381's in the batteries but no change. The batteries are fully lit but most of the other LED's are not. The EL34 CCS both have only two LED's partially lit and since both batteries behave the same way it leads me to believe it's a more centralized issue. What exactly I don't know...

It's better that way... or not...

Týr are awesome!!!

Well... there is no inductive load to drive here. Bridged amps are just a cheap way of getting more power by doubling up the amp modules. It's similar in practice to electrostatic amps with one pole driving each side of the transducer. In fact some of the very high power bridged amps with high rail voltages can be used to drive Stax... All of this does remind me that I really should do some electrostatic articles for Tyll but I'd rather just spend my time building something.