kevin gilmore

Certainly NOT a T2. Stacked output transistors. I've stayed away from designs like this because thermal tracking and bias problems can be very tricky. 1 extra milliamp in the output stage, and lots of burned up parts. If you do it as class B strictly as Koss does and put lots of feedback around it, it sounds like shit. At least it has the posibility of being completely DC coupled. It may in fact work really well. Someone would have to actually build it. with a total voltage supply of 1320 volts, the ratings on the output transistors is pushed past their max of 1200 volts. Clip the amplifier a few times and it likely smokes. Schematic as shown has an obvious and severe error at the minus input of the front end being grounded.

How much you wanna spend ?? Its this thing called johnson noise and is strictly due to the temperature of the amplifying parts... Which is why on my new cryoprobe, the 2 active preamps are cooled to 50 Kelvin. You get about 20db less noise this way. You can get most of the way there by dumping your amplifier into liquid N2.

NUCULAR isn't that how george bush spells it.... It certainly is how he pronounces it...

I smell a high priced military spec modification service being offered by APL. Say $1500 to modify your sr-71a. Actually a pair of the appropriately rated CRD's or fets wired for same would be better than either diodes, or resistors.

If this is true, then it is likely that the batteries charging the capacitors is causing an overcurrent condition and the batteries are turning off. Look up what the maximum output current for the battery is, replace the diodes with resistors to limit the maximum current. Should work fine. And drop less than the .7 volts that the diodes require. Don't ever get the batteries in backwards.

Because i'm to busy... My guess is that the current draw is actually too low to keep the battery protection circuit turned on. Some of the Li-ion batteries do that. They are designed for a minimum of 10% power draw. And justin clearly knows more about that circuit than resistor ray.

We now need a picture of tyll in a hawaii shirt, and a thong sitting on the bike... Then the people behind him really will have a crack in their windshield.

These headphones are comfy, block outside noise - CNN.com

This unit is just like every single other thing rudi has made. The finish is called solderbrite. The boards are still layed out by hand as evidenced the parallel traces not being parallel. Audio Research still does a lot of their stuff this way. The finish lasts no more than about 10 years before corrosion starts to cause trouble. I did a set of prototype boards this way about 20 years ago. And decided never again. it is a bunch cheaper because 2 less masks are needed.

No conformal circuit board coating on a portable?? Bad idea. Really bad idea. Very cheap ripoff of a tomahawk which is a ripoff of a ....

you are going to have beelly to recreate the sr71 hot tub incident

And done.

And replacing the electrostatic tweeter is going to be next to impossible, and i know of no one that is reconditioning those things. Still a very sweet speaker.

klh 9's soundlabs (with the direct drive tube amp) martin logan's dayton wrights (with piezo tweeters) esl56's tripple stacked with decca ribbon tweeters esl63's crown esl's with 15 inch dynamic bass drivers beveridge had them all, still have the esl63's

unscrew the connector, stretch out the techflex, pushing it back thru the rubber, use a single small cable tie to secure it.

You can be sure the construction techniques will be unique and highly proprietary.

Its more than BS, it is flat out wrong. Each secondary is wound with a specific wire size. The wire size dictates what the maximum current that particular winding is good for. So even if you take the two windings and put them in series, and then put the two 110 windings in series and tie to 110 volts, the maximum current you would get out of the thing is 4 amps. The fact is that using the most power hungry output tube you can find, all you are going to need is 10.6 amperes total. Unless of course its a balanced unit and then you need 21.2. At this point it is much more reasonable to wire multiple tubes in series to get the current down, same as craig does on the zana deux. The more current in a wire, the larger the magnetic field it generates. Which is one of the main reasons that filament wiring is usually heavily twisted pair, or DC.

Not the pico or ae2. Both of which kick ass. Mikhail, ray, justin and a few others are special people that put up with a lot to do what they do. Same thing with the 2 todds. Ray was up until recently the most sucessful of the bunch. No one would consider Tyll normal by any stretch of the imagination. I notice that AKG and Studer are now listed as owned by harman international. A sad day indeed for revox/studer. nagra is bound to be next.

Not in this economy. Krell is going to shrink by more than half over the next few years and has already laid off numerous valueable employees. Levinson was bought by Harmon Kardon who is now itself finally in a bit of money trouble. None of the levinson monoblocks are made anymore. Revel in similar shape. Crown now also owned by levinson. Not a good thing. Ayre and many of the other boutique companies are in severe trouble. Many great and not so great speaker manufacturers have gone out of business. Jeff Rowland fired his entire company something like twice now. I would much rather sit down and listen to the music, and get justin to build all the stuff i now want. Too hard to make money in this business, and too much work to build it for nothing.

266N12 transformer from mouser $34.37 plus shipping 266N12 crappy non-ventilated box, power connector,switch and wire $15.00 Mikhail's expert soldering job to put the piece of crap together.... PRICELESS

your wish is my command... Why doesn't mikhail's stuff look this good? Its 3 to 10 times as much money. And lookie just one umbilical connector, you can't plug it in wrong... http://gilmore.chem.northwestern.edu/zd01.jpg http://gilmore.chem.northwestern.edu/zd02.jpg http://gilmore.chem.northwestern.edu/zd03.jpg http://gilmore.chem.northwestern.edu/zd04.jpg http://gilmore.chem.northwestern.edu/zd05.jpg http://gilmore.chem.northwestern.edu/zd06.jpg http://gilmore.chem.northwestern.edu/zd07.jpg http://gilmore.chem.northwestern.edu/zd08.jpg http://gilmore.chem.northwestern.edu/zd09.jpg http://gilmore.chem.northwestern.edu/zd10.jpg http://gilmore.chem.northwestern.edu/zd11.jpg http://gilmore.chem.northwestern.edu/zd12.jpg and the original prototype (i think) http://gilmore.chem.northwestern.edu/xyzana1.jpg http://gilmore.chem.northwestern.edu/xyzana2.jpg http://gilmore.chem.northwestern.edu/xyzana3.jpg http://gilmore.chem.northwestern.edu/xyzana4.jpg http://gilmore.chem.northwestern.edu/xyzana5.jpg http://gilmore.chem.northwestern.edu/xyzana6.jpg http://gilmore.chem.northwestern.edu/xyzana7.jpg

and the correct answer is... So I am INCORRECT. Each filament is run at about 94% of rated power.

Here is the first answer back from craig, which did not answer my question, so i will try again. The external transformer in the picture is a 6.3 volt 8 amp transformer and is obviously the low voltage supply. That is NOT a 14 amp transformer.

you are taking tubes that are rated at 100 volts and pushing them to 350 volts. Some are going to take it, some are not going to take it. Some may take it, but have a very shortened lifetime. Where is the damm transporter when you need one. Economy air shipping from (xxxxx) but clearly over the pond takes too long.