kevin gilmore

Does anyone think it is a very lousy copy of this?? http://www.krellonline.com/krell_component.php?id=87&page=EVO202

Filbert at that other forum has said this (probably soon to be deleted) I'm not trying to troll you guys or make your lives difficult or whatnot. When I comment on something, it is in an effort to be helpful to the person I'm responding to. My comment was out of a genuine interest and concern. The current a portable amplifier outputs is going to come from the batteries, and the batteries are limited in capacity. In order to achieve a desired battery life, your current draw is going to have to be sufficiently low. You have to take into account not only the quiescent draw of the amplifier circuitry, but the draw of the headphones as well. As a result, based on the duration quoted here, it seems that it would have to drive your IEMs on a couple or few mA of current (depending on battery capacity), which is probably doable, but then there's a question of why you need an amplifier in the first place since many devices' internal amps will already source and sink that much current with pretty decent linearity and they're designed to handle the sort of load a headphone brings, whereas many micropower op-amps aren't (and even fewer could do so reasonably well). In order to get the equation above that level, it would take AAAs of a capacity I've at least never seen before or seen anything even close, but I'm not ruling out the possibility. I mention micropower op-amps as they're about the only thing that will get this low a quiescent current at this voltage, as well as the use of some of them might help explain artears' comment. I considered the use of micropower op-amps in some of the circuits I built over the summer, so I'm not unfamiliar with them. Thus, to me at least, it seemed as though my comments were reasonable. I would have made them irrespective of who made the amplifier. People who talk to me regularly I imagine will tell you I discuss the designs of a variety of devices, not just Ray's. I have to agree 100%. Many of the ipod and ipod like things i have checked into in the last few hours have at a minimum 4.8 volt batteries, most have 6 volt batteries, and i even found one with a 7.2 volt battery. All of these devices are going to be able to drive headphones better than something that runs on 3 volts.

From a lousy picture i was just shown it certainly looks like one big electrolytic (evidently ray's trademark) even though AA batteries really don't need it and one 8 pin soic package. So its not the maxim part, but it certainly could be the boomer part, or an ad8617 if he uses the split between the batteries as ground. The input and output jacks are the same kind of jacks that i have on a couple of my video cameras. They do seem to work, but boy are they cheap. So i'll downgrade my parts cost to $25 Evidently ray is trying very hard to keep decent pictures of the board from ever showing up. I guess i don't even understand why he is making such a product. Its probably identical to the chips already in many of the ipod and ipod like devices, whats the benefit??

The energizer non rechargable lithium l91 batteries are 4500 mah... at a current of 7ma you can certainly run a max4410 on these batteries for 400 hours. We will all know whether or not he is using a rail splitter on 3 volts as soon as a picture is taken. I'm sure ray needs new advertising to spruce up sales...

Nope, not an ad8397 as that can't run on 3 volts. My crystal ball is warmed up, so i predict the following Just about has to be this chip http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3459 Will know once i see pictures of the board. Which i will see sooner rather than later No rail splitter necessary. No honking big cap either. Total cost to build $30 Initial introductory price $199 Thereafter $250

Its the simplest of SRPP designs. It sounds like all amps of that particular topology. The output cap is size constrained. For high impedance headphones it is ok if you like that type of sound. It is nowhere near as bad as the hr-2 or hornet. It is not something i will likely listen to again. If i had to grade it i would give it a C-. There are so many things i would give a D- or F to... I think that fits into the "fairly good" range...

Well when i heard ray's system about 1.5 years ago it was just plain awful. For a whole bunch of reasons. Absolute crap turntable. Not sure what cartridge was in it. Ray's $5k phono preamp with absolutely no subsonics filter. Seriously underpowered amplifiers that were wasting 90+% of their power whacking the woofers around due to the subsonics. 2 way transmission line speakers with dynaudio drivers that remided me of an old eton madisound kit... Now ray has replaced those seriously underpowered amps with new cary amps and has replaced the turntable with a high line VPI which i'm sure has a lot less rumble. So his system is now up to just lousy. The only nice thing i can say about ray's speakers are that they have a wonderful paint job. Which seems to be the only thing ray actually cares about, the look and feel of his stuff. Those are $8k speakers ray said. I own wilsons, B&W, quad esl63's and celestions. Trust me, those ain't $8k speakers anymore than the phono preamp is $5k.

YES people 2 amps in series!!! An unbalanced amplifier drives one wire of the headphone and the other wire goes to ground. It has a specific output impedance. Take 2 of the same amplifiers and drive both sides of the headphone. The maximum output voltage swing doubles. The maximum available current does not change. The maximimum available power is 4 times. THE OUTPUT IMPEDANCE DOUBLES!!! Now if you have a solid state amplifier with an extremely low output impedance in the first place, doubling the output impedance has little effect. But when you have a tube amp with a 120 ohm output impedance (and you are kidding yourself if you actually believe that number for the raptor) you now have a balanced amplifier with an output impedance of 240 ohms. Really no kidding. This is how every single krell amplifier since the fpb series works. This is how every single solid state balanced output amplifier also works. (krell, parasound,big pass labs,crown....) If you really want to hear what a tube amp can do, get your hands on a pair of the small atmasphere amps and hook them up balanced to your headphones. You will be blown away. Circlotrons really work well for this.

What do you expect when you take 2 amplifiers with an output impedance that is already too high and put them in series? Something that can't even drive hd600's...

The whole thing is a joke. If you do replace 2 resistors in the raptor it sounds quite good with hd600/hd650's as you would expect out of the simplest of SRPP designs. For anything 150 ohms or less however it stinks. At least it does not start on fire anymore.

I agree.

I wonder if i'm also one of the few?? Let the trolling continue...

Not even close. My pic's are always 4000 x 3000 pixels cropped from 14mp. jpelg should be eating some shit shortly...

Its so nice to have a class act like Tuberoller here. Really Fred, i did not know you cared that much about me. Thats so sweet.

I stand corrected...

Here is a little "balanced" high end solid state entertainment http://gilmore.chem.northwestern.edu/nx33.jpg Best i could do from the pictures posted over there...

Earl let me be a bit more specific. The picture with the mpx3 and the 6y6g's is clearly for show. Some idiot may see this and try it themselves. Although it probably won't do any damage it won't work either.

Earl, I hate to pick on you or anything, but the 6y6g is a single pentode. It is not going to stick into any mpx3 unless you like the sound of one hand clapping. You are going to need a total of 4 of them to work in a mpx3. Same thing with el34's and 5881's, 6l6's or kt88's. Now the 6080/6as7 would work as those are a dual triode.

Just verified to be true. B52 power supply is exactly the same as 2 x original raptor power supplies with trendy toroid transformer and vertical standup ceramic thin film resistors replacing the 300 ohm series resistors. Lm317 for the filament regulator and Lm783 as the high voltage regulators. Ray is nothing except consistent. Take a piece of shit design and duplicate it many times. Working on schematic of B52 amplifier now, sure seems to be exactly the same as 2 x raptor's with the addition of one extra tube (per channel) to do the unbalanced to balanced conversion. Ray is going to croak when he finds out who sent me the pictures of the inside of the b52 amplifier chassis... $5k He has gotta be kidding.

directly from a person who had his unit upgraded. A particular crack on the plastic of a particular cap migrated to the new power supply. Also notice black caps in one picture, and blue caps in the next... Ray is saving $14... A poor immigrant needs to do such things

Not like i want to beat a dead horse or anything... plitron transformer pricing off line, equivalent hammond pricing $32.67 (100's) cincon cfm40s120 switching supply made in hong kong (EXACT PART!) $22.00 (100's) 470uf/400 volt CDE manufacturer (the blue ones in second picture) $4.99 (100's) 100uf/400volt nichicon $1.81 (100's) circuit board, input recepticle, switch, resistors and diodes, heatsink and regulator chip $20 (absolute max) (oops, lets not forget that oxygen free copper circuit board) So even at $200 ray is still making 100 percent profit even if its all brand new parts.

This just in... For all those people upgrading the power supply, ray actually de-solders all the electrolytics in the high voltage part from the old supply board and puts them on the new board to save money. What a high level of quality customer support. Brand new power supply with pre-burned in caps. Guess the 350 hours of burnin does not apply to this unit

Time for me to speak up again... That $8 switching supply is the same thing that is in the stealth. The ultimate in noisy miserable and unreliable piece of shit. Same thing in those $49 external hard disk drive enclosures. Lasts no more than 1.5 years before the primary rectifier caps explode. And heat will make it worse. Ray is the only person i know that can't even make a simple regulated 12 volt fillament supply thats quiet and efficient. Not sure why, there are at least 50 places he can steal one from. The high voltage supply is under rated for sure. And he is still using a 150 volt regulator part at 250 volts. The price is interesting however. A complete new power supply for $200. Add that to about $100 for the amp board, and you end up with something that really should have a retail price of $499. So those few people that said that the parts cost of the raptor was something north of $900 are completely out of whack. All those people who spent $1295 for a raptor now get to spend $200 for a power supply that runs cool, but is likely to explode 1.5 to 2 years later. What absolutely fabulous customer support. Sell a piece of shit that is way overpriced, then upgrade it with something even worse. How does ray get away with this. Go and buy a new production Zana Deux. Blows the crap out of the raptor for about the same amount of money.

The entire membran sacd collection is available from jpc.de for the unbelieveable price of about $5 per disc. All classical of course, the bach organ music (18 discs) is just wonderful. Also the olympia jazz sacd's (from the olympia jazz club in france) are available for about $10. Fixed price shipping of about $13 for all orders over $50.

http://www.diyaudio.com/forums/showthread.php?s=&threadid=82520 $249 plus shipping. You can run it at full power if you have 240 volts available for primary, or at 70% power if you run it as 120 in 120 out. Shipping for 100 lbs...