JimL

A fluorescent light kinda works.

That's it!

Direct-to-disc was the way that all recordings were made prior to WW II. Pros: minimal processing, short recording path, cons: if you made a mistake it was there forever. Some classic recordings from that era include the Schnabel complete Beethoven piano sonatas, among others (classic comment on those: "He got less of the notes and more of the music than any other interpreter."). The cons sometimes made for cautious playing due to fear of making mistakes. After WW II, when we discovered that Germany had developed a magnetic recording process, which Ampex and others perfected, nearly everyone went to analog tape until Doug Sax and a few others rediscovered direct-to-disc again, but the number of recordings made by that process were almost vanishingly small. Telarc put out a few DTD then switched to digital recordings. OTOH, editing also has its benefits. As mypasswordis has pointed out, some like Glenn Gould was an avid proponent of tape editing even and would patch and edit several playthroughs together in an attempt to get the "perfect" interpretation, whereas other artists would prefer to have a recording reflect their single best take, reserving editing only for wrong notes. But the one interpretive step that every recording has is: what microphones, and where are they placed? I would venture to guess that different recording engineers recording the same orchestra in the same location might choose different microphones in different locations. In the case of the cited recording, they are definitely using a "purist" technique with Blumlein "single point" microphones at a spot chosen to reflect their subjective notion of the "best" spot for catching the orchestra and the acoustic. Well, most of us haven't heard of most recording or mastering engineers. If you do a Google search, you'll find that he has written a text on audio mastering. I am in complete agreement with your last statement. One of my favorite recordings is Richter's live performance of Pictures at an Exhibition taken from a mono AM radio broadcast. There are times when the music-making just flat transcends the limitations of the media.

How is that even possible?!?

That seems like a rather flip comment. Consider this. You've heard live unprocessed sound, right? So you think you know what a live piano sounds like? A few years ago I was shopping for a piano. Every piano I played sounded a little different, some dramatically so. And that is true of EVERY acoustical instrument. Every live venue sounds different - Chicago Symphony Hall does not sound like Boston Symphony Hall. Different locations in the same hall sound different. I'm very used to the sound of a live piano - I have an excellent 7' grand piano at home. But the sound of a piano at the player's bench is not the same as the sound of the piano for someone listening to it seated several feet away. The first Stereophile test CD had J. Gordon Holt reading an article he had written, recorded using several different microphones. His voice sounded different on every microphone. So when you're listening to an "unprocessed" piano recording which you THINK sounds like a piano - what microphones were they using to record it? What hall was it recorded in? Where did thy place the microphones? What did that specific piano sound like? If you think about it, there is a processing step in even the most purist recording, and that is what microphones are chosen to do the recording, and where those microphones are placed. Because every microphone sounds different, and every location for those microphones sounds different. Those are the choices of the recording engineer. And by and large, we as consumers have no fucking idea about either, because that information is rarely published, and even if it were, most of us wouldn't know how to interpret it anyway. At best, the most we can say is, "gee, that sounds like my memory of what A piano sounds like." Note I say "A" piano, as most of us have never heard THE piano that was actually recorded. A mastering engineer is at least several steps closer to the original sound than you or I will ever be, unless you record your own reference material. They at least might have heard the original sound, in the studio or hall, perhaps chosen the microphones, have some idea of what was laid down on the tape. And, Katz has said that although the majority of his masterings have required some "sweetening", some have not, so he has certainly heard and mastered unprocessed recordings. And even if he is using "processed" recordings, he at least should know better than most what the recording "should" sound like. Look, I'm not saying that Katz is the be all and end all. I am saying that he is a very successful and experienced sound engineer and his descriptions and opinions are well worth listening to. Specifically I take his evaluation of tonal balance seriously because that is something that mastering engineers tend to be very particular about. But for the rest of us, who are using recordings where we don't know what microphones were used, where they were placed, what the original instruments really sounded like in the acoustic space they were recorded in, well... And that's assuming we are using acoustic instruments recorded in a live space for reference, and not a processed studio recording that never had an independent existence to begin with. Sure, one can criticize what amp he has chosen to test the headphones with, etc. That's perfectly legit. Any subjective review is only a guide, anyway. My tastes and priorities may be different, my reproduction chain is almost certainly different, there is definitely room for honest disagreement. What a dull world it would be if everyone agreed with me!

Uh, no. Building/modifying electrostatic amps and skiing is the closest I want to get to danger.

I actually stopped playing between about age 18 and 60, so when I restarted it was a little like learning to walk again. Which is why I got such a big kick out of Jason Stratham's line in the movie "Spy," where he plays a hyper masculine James Bond type: "I make a habit of doing what other people say I can't do: Walk through fire, waterski blindfolded, take up piano at a late age."

Stolen from one of my favorite pieces of snark when Wilson released version 53 or whatever of one of his speakers - "maybe this time he'll get it right. " Especially enjoyed it seeing as how I have a speaker that was designed over 60 years ago and only had one minor modification - the Quad electrostatic. PJ Walker got it right the first time.

Nope, bought it from a dealer in FL, of all places - high humidity, now in New Mexico, LOW humidity, so I have a DamppChaser to keep it humidified. I have tried a Fazioli - best piano I ever played, but WAAAYY expensive. Put it this way - when I was shopping, there were a few pianos that didn't sound as good as I thought I was, there were several pianos that sounded about as good as I thought I was - the Falcone was the least expensive, probably because they aren't made any more and most people don't know about them. The Fazioli was the only piano that made me sound better than I knew I was! Super-even action, totally responsive from a pianissimo to a triple forte. But even there, there were differences from one Fazioli to another. I'm sure you know, every instrument is different from every other.

A Steinway D won't fit in my condo, but I have a Falcone 7' that sounds pretty nice - this is the Falcone made by Santi Falcone in Haverhill, MA in 1988, not the stencil brand made by Sejung. Weighs about 900 lb with a 1.5" thick rim.

Currently there is a Woo WES and a HeadAmp KGSS-DX listed on ebay. http://www.ebay.com/itm/262862948306?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT http://www.ebay.com/itm/192110146358?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT Going to be interesting to see what they go for.

I believe he uses material that he has mastered, so he should have a pretty good idea of what it sounds like. He IS a mastering engineer, after all.

The Final Edition? Does this mean that this time he'll get it right?

Yeah, his labeling of frequency ranges is non-standard. But, as long as he specifies what he is referring to, which he does, you can translate his findings into your own terms. Yes, it's true that it is quite unlikely that two transducers are exactly 1 dB apart at all frequencies but otherwise have exactly the same frequency response. But as your argument concedes, by omission, in fact variations in transducers by 1 dB are not that uncommon, as any glance at the speaker measurements in HiFiNews or Stereophile will show, and are generally considered within specification. For example, IIRC, the Sennheiser HD650 is supposed to have hand selected transducers that match within 1 dB - granted, a much less expensive phone, but when it came out it was considered top of the line. But it illustrates the fact that mechanical transducers will, in fact, vary, and so there is ALWAYS a matching issue. So I'm not at all sure that a 1 dB mismatch isn't within specification, and would not be considered poorly matched. I haven't been able to find any specification from Focal as to closely matched the Utopia is supposed to be. But, on the other side, the presumption has to be that any headphone that has been put on sale is within specification. Now, if Focal sees Bob's review and says, hey, this headphone is defective and shouldn't have been sold in the first place, that's another matter. But, if Focal has a QC issue, that should be reported, shouldn't it?

Oh, I dunno. It seems to me he goes into detail about how he and his intern listened to both the Amb and Audeze with both headphones and couldn't distinguish between them, so that seems to be a fair characterization, at least as far as the headphones under test are concerned. In any case, even if someone else could distinguish between them, it would seem that the differences between the amps is significantly smaller than the differences between headphones. In terms of the 1 dB difference, he specifically states that the whole stereo image was shifted, so presumably one driver was less sensitive than the other. Since he borrowed the Utopias in the first place, it wouldn't be likely that he could just request a replacement, as opposed to the owner, who could. Also, I don't know that Bob has measuring equipment for headphones. After all, reviewing headphones really isn't his job, so I take it for what it's worth, a subjective review by an experienced listener. Although the introduction does seem to claim that his speaker system is the best, he also clearly states a bit later on that "This is the most natural-sounding and accurate loudspeaker system/room I have constructed in 46 years of audiophile and professional life." That seems to be reasonable. Finally, in terms of EQ, if you've read his stuff you will find that he is a fan of EQ in moderation, and has ear-tested his EQ equipment to determine that it is transparent, to his satisfaction. Also, he has stated in the past that some of his best mastering work has required some degree of EQ to sound its best, and that in his considerable experience, most recordings have had some degree of EQ (determined by ear), and as he is both a successful mastering engineer and has written a textbook on the subject, he probably has a point.

I did on mine, but probably doesn't make much difference, if any.

If you are using the on-board rectifier diodes on the PS board, you can use the same transformer as a KGST - same voltage, a bit less current needed. On the other hand if you built a choke input power supply as in my original schematic (P. 4 of this thread, posted 9/16/16, 3rd from the bottom) , which means the rectifiers are off-board running into a choke input, and the output from the chokes goes to the PS board, you will need 800-850VCT - I know my schematic shows 780VCT but that is actually too low.

The voltage depends on whether you use a choke input or capacitor input. Basically, any transformer that would work for a KGST would work for the SRX Plus using a cap input filter. If you use a capacitor input filter then the voltage is higher than needed - although remember unless you have a regulated AC line, the voltage may drop 10-20% in the summer with all the air conditioners, etc, so you need to allow for that. When you do that, then the DC output from the cap filter could be 20% low, which would decrease it to around +/-390 volts. In that case, if you are allowing for worst case 20% low, 700 volts would be ample. On the other hand, if you are only allowing for 10% low AC line, then 600-650 VCT would probably work. I haven't checked recently to see what is recommended for the KGST but it would work equally well for for the SRX Plus, since both can run on +/-350 VDC. If you use a choke input filter, the voltage would actually be less than the AC voltage, e.g. around +/-330-340 volts, so that 800V-850CT would be a better bet. On my build, the transformer was specified at 780VCT and I had to decrease the PS output voltages to around +/-315 volts to get enough headroom for regulation. For the shunt PS, I would set the shunt so the 10 ohm test resistor has about 0.43-0.45 volts across it. Remember that my most recent revision of the PS has moved the capacitor at the 431 regulator from between the reference terminal and ground, to between the reference terminal and cathode. That is not reflected in the PS circuit board so you'll have to cut a couple of traces and solder new ones to the back side.

Great job, spritzer and congratulations! Perfect for those cold Icelandic summers.

Great! Glad that you got it sorted out. Enjoy!

There were a few reasons for using 6SN7GTA/GTB output tubes rather than 6SN7GTs. First, a higher voltage and power rating, which means that we are working in a more linear part of the tube curves, second, there are new tubes available for those who don't wish to mess with NOS, third, the original GT tubes actually have lower voltage and power ratings than the 6CG7/6FQ7 tubes specified in the original SRX design, and fourth, NOS GTA/B tubes are still reasonably priced, whereas some 6SN7GT tubes are going for silly money these days.

Actually, you could run 6SN7GTs in the SRX Plus, you just need to cut down the voltage to, say +/-250 volts for B+ and cut down the output standing current to 6mA per section. You would lose about 3 dB in ultimate loudness but if you listen at reasonable levels that shouldn't be too much of a problem.

blubliss, I thought you had a SinglePower ES-1 that had been modified to work properly?

I asked sorrodje (Pierre) to post on the SRX Plus because I haven't had a chance to compare it much with other stat amps, so I was curious about other people's impressions of it. If you're not familiar with him from Head-Fi, he has a nice measurements and sonic impressions post on SBAF in collaboration with Ali-Pacha of about 10 Stax headphones ranging from the SR-5 (my very first Stax headphone) to the L700, and including the SR007 and 009.

I've been too busy to hook up my amp after changing the PS until just before the weekend, and discovered that it was much noisier than before even though the PS was quieter, so after going through everything I tried replacing the 10M90S in the input tail current source with the DN2540 that was there initially. Less noise though still not back to the best. So I no longer recommend using the 10M90S in the input current source. Sorry about that. Haven't had any hum problems, though.