kevin gilmore

I'll add that it can't meet the gain and distortion numbers if it is only the 2 tubes in the audio circuit. At most you are going to get a voltage gain of 100, and you really need a minimum of 500, and really 60db which is 1000.

here is my opinion on that OTHER site. Wonder how long it will last. Actually my take on this amplifier is a bit different given hints from rudi's website. If you believe the distortion numbers rudi quotes then clearly there is significant feedback in the amplifier. Therefore each of the 4 output sections is likely to be a composite amplifier with 1 section of a 12ax7 triode connected to a el34 wired as a triode with feedback around this section. Then the input is rudi's unbalanced to balanced autoswitching balanced to balanced input stage which is all opamps. If you look at the amp chassis however, there is no indications of any external heatsinks. If you run the el34's at their sweet spot of about 10 watts each, then somewhere there is going to be plate resistors or constant current sources that dissipate 40 additional watts. If that is inside the chassis as it certainly has to be the thing is going to get very hot. Probably the best thing rudi has done to date. Certainly the most expensive. There were a few burmeister electrostatic amps built, they were $25k each. Evidently they were worth it. __________________ Quando Omni Flunkus Moritati Now the stuff that would be deleted over there... No more box of boxes, i'm disapointed. limited to 400vrms HOW??? And why would you anyway. And if it can do 700vrms is that stator to stator, or stator to ground. Notice the low frequency cutoff is 2 hz. Yeah bullshit, and it also means its a capacitively coupled output. Back to that correct spectral harmonic compensation thing (politically correct version 3)

a bit more work http://gilmore.chem.northwestern.edu/hammer3.jpg

my serial number is better than yours... Ask justin

Yep and then the arm twisting behind the scenes to get wakeride74 to change his opinion. Yes the spin is working overtime.

Wonder when ray is going to go back to his nasty old trick of shipping his product to some of justin's pre-orders. Just like he did back in the amp wars days when he sent his amplifiers on eval to anyone interested in a singlepower.

Buy the 900 volt parts. Really. You should not run them at more than 50ma each. You can try the 450v parts, I have not tried this. Getting 3 of them in series to correctly voltage share might be tricky. If you raise the voltage rails past +/-400 you have to change out the 2sa1156 with a 2sa1486. Then you can probably go to +/-550. Everything else references the two rails, so there should be no other changes.

Well its a new year, and it is certainly starting with a bang. I do like flashbak's quote that the dac in the pico was superior to the one in the predator, and then ray's fanboys jump all over him. Great stuff. For portable amplifiers that use 9 volt batteries (sr71,hornet and a whole bunch of others) and are not class A (none are) the impedance of the battery is an issue because 9 volt batteries are a high impedance. So you slap a cap (4 for the sr71) across the battery to lower the impedance so that the audio does not modulate the power supply. But lithium batteries are anything but a high impedance. In fact the lithium battery inside ray's predator has a lower output impedance than that big honking electrolytic cap that is in parallel with it. A huge waste of realestate. So he perpetuates the myth that the cap makes all the difference, and the cap takes 600 hours to charge. And then he puts in an ultra crapo and in my opinion dangerous lithium battery charging circuit. I'd post the necessary equations to show that a 15000 uf cap takes less than 2 seconds to charge from a 9 volt battery, and much less than that for a lithium battery, but i'm just a touch hung over, and about to start the new years festivities. Ray really has lost it on this one.

You would put 2 of them in parallel, not in series. In parallel with suitable heatsinking you can get to about 100ma. You could put 2 in series to get twice the voltage swing (say 1800 volts) but then there are going to be voltage breakdown issues and they have to be heatsinked very carefully and probably with berylliumoxide insulating washers. (which are toxic if not handled right)

I would think that being compared to the greats such as Nelson Pass, James Bongiorno, Dan D'Agostino and Charles Hansen would definitely be a good thing.

The back to back zeners need to be 100v not 81v.

That is great for knives, might work for a chisel. Not nearly thick enough for knobs. Will contact him and see if he can supply what i need as raw material. Price is certainly reaasonable.

Maybe you have never played with a real jewelers hammer. The design was specifically for the function of perfect use. Perfect balance... There is 30 hours of machining time in that hammer at the moment. Guess i wll have to try harder. What do i have to do to get that 9 turned into a 10?? Maybe your opinion will change once it is finished. I have OH so many uses for that chunk of damascus. More uses than i have steel. For the knob, it would have to be cut out of the side, because you clearly want the lines going across the face of the knob as well as the sides of the knob. That eats up a lot more of the material. And if i want the chisel to have lines all over the main face, i have to cut it from a chunk at something like a 20 degree angle. So the material is going to be used up quite quickly. I can certainly make a damascus toothpick, but i think it would be a real bad idea to ever actually use it. If anyone actually knows where to buy raw chunks of damascus, i would be very interested, and i really don't care how much it costs. Once is fine as a joke, but i really don't want to burn most of the hair off my arms again.

The KGSS design is 8 years old now. There are lots of things that can and will be done to this design. Better current sources, even better front end transistor/fet, stronger and faster output devices. Maybe i'll even publish the fully complementary differential design i have had for a few years now. Lots of parts. Bigger and better power supply always a good thing. Not going to get into the Me vs Mikhail thing. But it sure would be nice to see someone else doing actually new designs.

This is the first, and probably the last time i'm going to try something like this. I have absolutely no idea what the final steel is going to look like. I started with 25 layers of various scrap steel. All cut to 3 inches wide and 10 inches long. Stacked as flat as i could get them, about 2.5 inches thick, then i arc welded the sides in 4 places each to get one big hunk of stuff. Then melted the piss out of it, and used a 10 ton press to bang the crap out of it, then heat it up again, and use the press again with a cutting head to cut through most of it, then bend it and heat it again then beat the crap out of it again. I did this 4 times. No way was i going to pound on this stuff with a hammer for 8 hours. The last time i did something that stupid i had tennis elbow for almost 2 years. I'm probably through heating and banging it. I want the finished piece to be 1 inch wide at the head, and the shaft about .5 inches in diameter, so i'll have plenty left. No idea of hardness. I envy the guys in japan that make those presentation swords. Then again for the prices they charge...

So this is the time of the year from thanksgiving to new years where i have the time to do extraordinary projects. This year is no exception. So i delivered the hydrogen torch preamp prototype to a person in chicago that happens to own a ctc blowtorch with great success. (hearafter just refered to as just hydrogen)(a hydrogen torch is at least twice the temperature of a blowtorch) But this year i wanted to do something extremely over the top just for me. And while it is not done yet, enough of it is done for a couple of pictures. So I hereby present the $5000 hammer. (in fact its going to cost way more than that) http://gilmore.chem.northwestern.edu/hammer1.jpg http://gilmore.chem.northwestern.edu/hammer2.jpg Handle and head machined from a solid piece of titanium. Handle drilled out for perfect balance. Standard taper on the handle. Shown with 24k gold and phosphor bronze hammerheads. Also shown with black and white delrin and stainless steel replacement hammerheads. Still have to finish the pure platinum, pure silver, lead, copper and lignum vitae hammerheads. As well as the (probably burlwood) wood insert for the presentation case. Going shopping tomorrow for the burlwood. Still don't have enough rhodium to make a hammerhead (or anything else) and research safety has decided that i will not be allowed to machine up the chunk of beryllium that i have due to possible exposure to beryllium dust. I'm almost done making a chunk of my very own damascus steel, which i'm going to machine into a chisel that goes with the hammer. Maybe at the next meet in chicago i'll bring it along and attempt a couple of love taps to the extremely hard head of my good friend ray. Happy holidays.

koss esp950's are bass heavy with low bias. Best sound is about 620 volts of bias. And they can play very loud.

You can make the 6.8k resistor a 10k pot, that should give you more than enough range.

Raising one voltage does you no good. You have to raise both of them. If you replace the 2sa1156's with 2sa1413's then you can get to +/-550 Or if you replace the 2sa1156's with 2sa1968's you can probably get to +/-700

If you are going to try DHT's, you are going to have to have 4 completely seperate filament power supplys. Reason, 50 volts of audio on the cathode and opposite in phase with the other tube in the same channel.

Actually there are 2 ways. You do it, or you get someone to do it for you. The 3d21's would definitely work in a BH. But really they want to be run at 1kv+ and then you have to put current sources in series or otherwise they smoke.

I'm pretty sure i tried kt77's at one point, the skinny bottle versions should be a complete identical replacement. (I think, don't really remember) el360's are virtually impossible to find, and when you do they are chinese junk and the top cap likes to come off. kt88's, 6l6's and things like that seem a bit ratty when you run them all the way to 800 volts.

More than willing to hire 3 people. Its two of the three i can't find.

wanna bet?? Been looking for over a year now. I could just give in and take the next piece of trash that shows up, but the people above me would stop it anyway. Real money is involved as in 75 million a year. Goverment cost accounting standards. Gets messy if an idiot makes a mess out of everything.

Bingo. Also need someone that can do sql all day long.