kevin gilmore

- 6BZ7/6BQ7A are on the input in paralled and are setup in a 'proprietary circuit' that provides ~6db of gain and has the primary purpose of presenting 100ohms impedance to the rest of the circuit, regardless of the impedance of the source. That would be a differential amplifier with a gain of 6db and cathode follower. Hardly proprietary as this is exactly the same circuit that ray uses in the B52 front end. (subject to picture verification) Also 100 ohm output impedance of that tube as a cathode follower is just not possible. More like 2k. But still a fairly low impedance output for tubes. - 6CG7/6GU7 are in parallel and work in conjunction with the 27GB5/PL500 for the output. For each side of each channel 2 triode sections are in parallel. True - The 27GB5 are in a way setup to be the CCS for the 6CG7. An interesting way to describe an inverted cathode follower. - If you want to say one tube is on the output, it is the 27GB5. The 27GB5 certainly has the lowest impedance path to the headphones. Someone was asking me the output power of the amp recently... can't remember who. Anyways, he said that if you were to give it a wattage rating, it would be 6 watts. Into what impedance?? Certainly nothing in the range of 32 to 300 ohms. (but i'll go and calculate it) He also said that is not the best way to rate the power of a headphone amp since it tells you hardly anything about its ability to drive various headphones. He said a better way to put it is 98volts peak to peak. When I asked him about current, he said that it could put out 600mA at 100volts easily enough. Someone is smoking something! Besides which this is clearly irrevelant. I asked him about output impedance again and he gave me the same answer, 40ohms. UH maybe. small signal only into medium impedances. EDIT: He also said that the 27GB5s are in triode mode. TRUE.

You go and convince Jason to let me do this... Then i can probably knock it out in a weekend.

I'm joking of course except i'm not really joking. Duplicating jason's unit with point to point wiring done woo audio style would be god awful amounts of labor, and therefore out of line expense wise. So the thing i would really do is do a complete circuit board layout. All of the parts one one board of about 10 x 15 inches. With a group buy of boards something this size would likely be about $75 each. It would probably take me less time to layout the board, than to actually build one. A lot less time. Might even make it 2 dual mono boards, so you could build the thing as unbalanced only. Then just about anyone could stuff the parts and build the thing. Do it right with a real chassis, or a complete abortion like that wood thing that jason built. You could build it ray samuels style (tubes on one side, all the parts on the other) or justin wilson style (all the parts on one side of the board) Hell i can even layout the board singlepower style with all the tubes at 45 degree angles. For the record regardless of what has been previously said about jason's unit, there is absolutely nothing new in the design that has not been done hundreds of times before. Nothing new, nothing proprietary nothing out of the ordinary... Although the tube compliment is a bit unusual.

Maybe i should get into the business of upgrading/repairing singlepower and mcalister stuff. Sounds like a full time job to me A complete rebuild of jason's amp (same exact design, built correctly) is about $500 in parts plus about 30 hours of labor. At my labor rates that would be about $5750. Special discount for jason only.... $3000 Maybe mikhail might want to do that design in a dual box setup. Got to be >$9000 .....

spoilers One of the writers Aaron Douglas specifically said that 4 of the 5 final cylons would be revealed in the seaon finale. spoilers

After i get the final pictures from jason and then if he will let me i will post the schematic. Then some of you with the knowledge of whats going on will have a field day with the design...

They are all true!!! A friend of mine works in an appropriate place to get the episodes complete sans commercials. I saw the second part like 3 weeks ago... Hopefully next year i can get the same stuff the same way except in hi-def. Its far more intense to watch when its 43 minutes complete in one shot. Final episode is actually 4 minutes longer, so its 47 minutes.

Now that would be cheating NO??? Besides which the person that makes that "other" tube amp would argue it is completely different when it is actually 95% the same This is pretty much the last time i'm going to ask that particular person to send me the electrostatic portable transformer he has promised to send me for over 6 months now. After that a whole bunch of schematics and pictures may just have to appear

Jason was wrong. Before the final upgrade the 27gb5's were the active top current sources The 2 sections of each of the 6cg7 were in parallel and were the output gain stage tubes. The 6h30's were doing absolutely nothing usefull !!!!! (If you haven't figured it out by now, I have the schematic!) After the upgrade (i'm guessing here) The 2 sections of the 6bz7's are in parallel and 2 of them form an input stage differential amplifier. Same as the input stage of the B52. So you can supply balanced input, or unbalanced input. And then everything else is the same.

Open offer still stands. You send me a dozen of the same tubes. You label them in any way you want that will not rub off. I will randomly cryo half of them. I'll send them all back. You try and tell the difference. Your choice of 2 days at liquid nitrogen temperatures, (77 degrees kelvin) or if you really want, 2 days at liquid helium temperatures (4 degrees kelvin) No charge for the cryogens or use of the dewars. Students at northwestern university can verify that i actually did this. So far no one wants to take me up on the challenge...

The 6bz7's are most certainly in the input section, and not any part of the output section. There are large output tubes for the active current sources and other tubes with paralleled sections as the output amplification element. Don't remember the exact tube compliment at the moment. Similar in design to another tube amplifier well liked around these parts. Also remember that this is a balanced amplifier.

alrighty then, major spoilers below * The fleet realizes the Cylons are somehow following it to Earth. * Tigh talks to Six about it, but their conversation (thanks to Six

Nothing wrong with that. Nothing right with that either. Two boxes instead of one. Two sets of batteries instead of one. Two volume controls instead of one. Twice the physical size for absolutely no apparent gain. Have a happy new year.

the interconnect cable is of insufficient diameter the amp chip in the ipod and in the tomahawk are in fact one in the same. Notice how few views for a post that has been around 18 hours. I really think that ray should get into the trendy $100 per inch cable business. Happy holidays. Certainly the best for me in a great many years, although i can't say why yet

spark plug wires? That is so last century. Everything performance related these days is single coil over spark plug per cylinder.

I told mikhail almost 3 years ago now to produce an amp like this. Better late than never. Earl: you forgot the 6336. and probably a couple of others.

Billy, if spending $4500 on a preamp makes you sick, you are gonna be sick a whole lot in the future. In 10 years when you look back on the $150k you have spent on audio you will probably have a heart atack. Lets not even discuss cars...

Kevin's review of the B52 from the pictures ray has posted. THE GOOD The aestetics of this unit are very nice. Still way to many ray samuels logo's and the logo's are way to big. But i happen to like the looks of the thing. KG's rating---- A- The quality of assembly, the quality of the parts, the quality of the layout. Outstanding. A particular company north of the border should look at how things are supposed to be done. KG's rating---- A At least the box is finally big enough so the electrolytics won't burn up due to the heat. Still a few more holes in the main board would definitely help. THE BAD Circuitry description. Differential amplifier on the input. Turns unbalanced signals into balanced or amplifies balanced signals. Output capacitively coupled to the 4 channel dact step attenuator. Output of the attenuator goes two places, one is the cathode follower preamp output stage, and the other is the balanced srpp headphone amplifier stage. KG's rating ---- C- Yes in fact as far as a headphone amp is concerned its 2 raptors in one box. As a preamp it has a cathode follower output stage, so it actually really behaves like as a preamp. Output impedance of about 2k is far better than the 100k impedance of the stealth. I feel sorry for all those stuck with stealth's which are now completely worthless. Yes the headphone stage is TWO SRPP stages in series with TWO output capacitors in series with the headphone. Double the output impedance. Double the slush bucket bass into low impedance headphones. THE UGLY What is this thing. A preamp?? If so where is the remote control. A Headphone amp?? Where is the low output impedance. Instead of doing one thing right, it does two things wrong. First thing if you really are going to use it as a preamp, chuck the 2 x 12au7 preamp output tubes and replace with 6n1p (after dealing with the filament voltage issue). But really with the same number of tubes and deleting the headphone output it would be easy to design a new board that fits into the same chassis and turns the thing into a conrad johnson clone. Plenty of room now for composite triodes. FOR A FEW PENNIES MORE ray could have actually added 2 wires into the power supply cable and avoided contaminating the high voltage ground with the grunge produced by the ultra cheapo fillament switchers. The B52 really is the best thing by far that ray has ever done. Stereophile should eat the thing up.

Aerius please pay attention. That tube is completely and utterly useless for otl audio applications. Look at the Rp. Look at the fact that the sweet spot is 2500 volts and about 500ma. Decent output caps for that thing would be about the size of a gallon of milk. EACH.

Rayvistors, right you are. I still can't find any of the boxes... But here is a new one. JVC's brand new 1080p 3 chip dila projector is called the "RS1" about $10k list, 8k street. I'm on the list for one sometime in early february.

Yes i have designed one. The wj211 tube last time i checked was about $8900 each. You need 2. 4 for balanced.

yes i believe in some current production tubes. Unfortunately virtually none of them are usable for audio unless you are completely nuts. Eimac (now independent again) makes wonderful ceramic triodes and tetrodes. The new western electric makes some pretty good 300B's. Way better than any other chinese junk, but still not as good as the originals. Hammamatsu makes some truely amazing products. In fact they make an amplifier tube so linear (and 50 ohm output) that works great as a headphone amp tube. Trouble is they are about $650 each. You need 2, and they would last virtually forever. Watkins-Johnson makes some very nice stuff too. They also make a 50 ohm output ultra low noise amplifier tube. You don't want to know the price.

I agree with number 4. There are however tons of tungsol NOS 6080's available.

I believe they were called hornets. I have a few somewhere.

Actually it is still up. I figured someone would have taken it down by now. The people at the kindercare next door were all cheering my sign. I thought the area i live in was died in the wool redneck republicans, but maybe not.