erik2A3

Good! It would be a great preamp for three times the price. His first book is also excellent, though maybe a bit more technical than Audio Reality. The author shares some of his early designs, including the preamp I built in the early 90s - in my case, from the schematic that was published in Glass Audio magazine. The very negative commentary is just....unfortunate.

With Lowther PM5A back-loaded horns, are TS SEOTL (left) and TS Phono stage and Masterpiece, top to bottom respectively in the center. And edit: For the sake clarification, the SEOTL mentioned here is Rozenblit's original version.

I built the TS phono stage I am using now for MM pickups. Very high gain, quiet backgrounds, and, to my ears, a sort of combined quality of tube air and finesse with very satisfactory (also subjective) low end response. I had heard prior to purchase that there was the possibility of certain circuit revisions, but to my knowledge there have been no changes made; which is definitely ok with me. It has been a great match with the Masterpiece 300B preamp/headphone amp, and really any other linestage with which I've used it. *As a footnote I would say that while the Grounded-Grid mentioned above would be a good first project for someone (after practicing a bit of both through-hole PCB and basic point-to-point wiring and soldering - none of which being a particulalrly big deal once one gets the hang of it - in some useful and great-sounding DIYing at a great price, the Masterpiece is not so well-suited, IMO, to the new builder.

The standard potentiometer included in the kit is actually quite good. It is the common carbon-composition type which, while being sonically very decent and satisfactory (at least to me), the problem one often encounters is comparatively poor channel-to-channel tracking between the two sections. What I have done in the past when building a preamp, integrated amplifier, passive inline attenuator, etc., is to buy several (since they are very inexpensive) and measure each in order find the one with the closest value tolerance (50k, 100k, and so on). The Alps VCs are overall much better controls in this respect, as of course are those consisting of fixed resistors in stepped controls (which Transcendent Sound) also used to offer as a kit. I use the blue Alps almost exclusively now, though a year or two ago completely rebuilt a LEAK ST20 stereo power amplifier with a stereo carbon strip pot that had essentially identical tracking between the two sections. it was used in place of the usual grid-leak resistor which sets the input impedance to the amplifier. I have also built the Grounded Grid for a friend in Europe, who asked for not only dual-mono pots (linear taper) for improved L/R balance, but also a master volume control (log taper) to be used for general, day-to-day listening once the the two input attenuators had been set at a desired level. It required modification of the faceplate, but worked quite well. So great! enjoy your equipment! If you like the GG, which I also do, at some point you may like to consider the much more recent TS Masterpiece. It's definitely a far more involved build, but is an extraordinary component.

DRD 45 is outstanding, as are the 2a3 and 300B versions. A circuit designed by Jack Eliano, who also winds the transformers.

I have two K400horns and two K77 tweeters (both with ceramic mag drivers) I had planned to use for another project. All in good working condition if interested. Good luck on your La scala build!

We also had the JM Peach here during it's roadshow - and I will say it's on par with the Grounded Grid. My wife adored the Peach, both for its outstanding flexibility and its great looks (relative to my many bud box experiments). I would still consider purchasing a Peach if one came up for a good price - just to throw into the system for a sonic change of Pace. JM designer was also one heck of a clever guy with audio circuits.

Transcendent Masterpiece is still simply amazing. I neglected to mentioned that I have built several Grounded Grids, including my own, and I do agree it is also an outstanding performer. If one has to have long ICs due to amplifiers being some distance from sources and preamp, the Masterpiece has extremely good current drive capability. It's difficult for many preamps to drive the associated capacitance of longer interconnects, particularly where the output impedance of the line stage is on the high side. I had studied grounded grid circuits in schematics of receiving and transmitting radios for years. Rozenblit took advantage of their very high speed capability and behavior and employed them in the Grounded Grid linestage. Very agile and quick little preamp that is both a snap to build and a giant killer as it relates to cost vs performance. I also built Bruce Rozenblit's very first published dual-output (high and low output z) preamp from scratch in the early 90s from an article he wrote for Glass Audio. A truly innovative designer. The Masterpiece is all point-to-point wired and likely not so well suited to the beginning builder. As a headphone amp it is really jaw-dropping. Seriously good sound from its 300Bs, and quite literally dead-quiet for headphones and high efficiency horns alike.

Those of you who mentioned the GG need to hear the Transcendent Masterpiece. Stunning good.

Chris A (and of course other contributers here) I appreciate the time you took to share that information and images here. I've read some of your other posts with great interest, as well. You have definitely put some effort into this! And "Supper's Ready". Absolutely one of my all time favorites from Genesis. I will say I also really like Collins doing the vocals on the Seconds Out version. With Bill Bruford, Chester Thompson, and of course Phil himself doing the drumming on that album, the percussion is amazing. All of it is good though! From measurements I've done in the room where they would go, the K402s would be about 12 feet apart. Does that seem doable? DizRotus: I wondered the same thing about my original post...maybe it was deleted in favor Schu's munching pet cow - which I admit is much more funny than mine. But what happened, I wonder? deleted for some reason?

What makes a recording bad, better, good, or best? I suspect we all have our own goals and objectives when it comes to spending hard-earned cash on audio playback equipment. One of my primary goals in choosing loudspeakers has been transparency, clarity, detail, and fidelity to recording. All of these traits often mean different things to different people, particulalrly the last element, since it's hard to know how faithful a reproduction of a recording is being presented without having been present at the studio (or other venue). Even then we are are ultimately left with the colorations and artifacts imposed on the signal by the recording equipment used. If it's on the recording, I want to hear it...horn or woodwind musucians breathing between notes, fingers sliding on frets of guitars, brushes on cymbals, and so on. Those are the sounds that to me help generate the most organic and 'living' recreation of a recorded musical event. The crossoverless Lowther PM5A drivers I have installed in large, back-loaded horns are more efficient and ruthlessly (or truthfully) revealing than were our Klipschorns or our present LaScalas. The drivers alone cost $2.5K. The response of this system is far from linear, and driver impedance is all over the map. Some use swamping resistors and other equalization (zobel) networks, in attempt to reduce crazy impedance fluctuations. I have tried all of them over the past 20 years; and as someone who has played music in live entertainment settings, prefer the sound of these horn loaded (or open baffle mounted) drivers totally bare. The more of an open - or at least very clearly polished - a given system is to the reproduction of a recording, the better...for me. Dean, I remember a long time ago you described Klipschorns as great for tearing one's ears off one's head (or making them bleed...something to that effect), so I can thus understand your cautions regarding the K402. However, it's the qualities you are warning against that are precisely the reason I am interested in them. At this stage in my life I listen almost exclusively to acoustic jazz and classical, with occasional prog rock/fusion thrown in here and there for old-times sake -- Jeff Beck, Yes, King Crimson, older Genesis. The K402s might be the door even more widely open onto those captured musical events...for me.

Very nice! Right, so on the T16, only one input tube compliment is used, thus the three unused punch-outs for tube sockets on each amp. I built both of mine as stereo amplifiers - I bought the second off a friend from Mexico for whom I built it a couple of years or so earlier. He went solid state with everything, that he said just sounded better with his low efficiency monitors and original Quads. So, with those socket holes already occupied, I was going to leave them as is - or maybe just for fun, disconnect grid, cathode, and plate connections in place on the one unused input/driver stage, leaving the filament suppy in place. Or, who knows, possibly just sell the second stereo T16. I have never really needed that much power, but was going to use them as monoblocks for the Lascala bass bins with a plan for an open baffle using our Lowther PM5A drivers, with a low pass filter to the woofers at around 200 cps, or so. I've already experimented with this a bit, though the choke I happened to have on hand crossed over at a slightly higher frequency than would a final rendition. The LS bass bins were placed in corners (though not tightly the way we did the k-horns once upon a time), wired out of phase, with the mouth of the horns firing toward the corners rather than the listening position. This was a simple, bi-amped system, using a rebuilt Leak ST 20 (with on-board volume control I installed -- essentially an in-line attenuator (aka 'passive preamp), and Transcendent SEOTL (original version) on the 15 ohm Lowther drivers. Many Lowther users (including Nelson Pass) have abandoned the back-loaded horn approach, for which these full-range (not quite) drivers were traditionally used, opting instead for open baffles, and I have to say the sound the arrangement provided was positively superb -- electrostatic-like, with a fantastic and lively sense of air and space. I have been using the Fostex T90A super tweeter with the rear loaded horns, with a series poly film cap giving a response at around 10K Hz, but with the Lowther driver positioned on the open baffle on-axis at ear-level, I found the HF response of the Lowther alone very satisfactory. I ordered these particular drivers with silver voice coils, which seems to have a bit pf a taming effect, without any dulling of clean, clear transient response. Totally attention grabbing sound! Grand Funk!

Steve, GG and SOB must be a really great combination! I've built several GGs, but never for myself! My wife recently bought me one for an anniversary present; She knows how much I liked every one I've built, and we have need for another preamp in a second system. I'm intending to use the Masterpiece primarily for its much greater immunity against the negative effects of capacitance associated with long runs of interconnect, but I am enjoying it so much as such really, really fine headphone amp that I've been slow in getting into the main system. Thank you for including the TS link. Meant to do that, but just forgot. I think the high power OTL 'Beast' would be lots of fun, but with speakers with an efficiency of 104 and 105 dB/watt, I have no need of that kind of power. I have two T-16s soon to be rewired as monoblocks, and that is even far more than I need. Amazing to think that's a total of 44 valves between the two amps....

Moth Audio (now Eddie Current) used them in the first edition of the si2a3 amp. However, in that design, all tranformers and filter chokes are under the hood in a very deep chassis (top to bottom), and thus are out of sight. Toroidals are excellent, and I agree in many circles they are considered to be superior to what is more commonly seen. BTW: I built Rozenblit's very first linestage from scratch from the schematic published Glass Audio back in the early 90s. It was a dual-output impedance (high and low) which, while very good at the time, does not come close to the performance of this latest design using 300Bs.

Note! the image above was taken just after voltages measurements, and the first listen to music. Bottomless and control knobless, just to give it a first listen. Honestly something very special. I beg you to NOT ask me the brand of coupling capacitors it uses......

I've complimented TS OTL amps and preamps multiple times over the years, having built them in the past both for other forum members and myself -- who some older folks here will remember as writing under my original Klipsch forum handle -- Erik Mandaville, which goes back to about 2002. Some years those early years were, too! Whew! I recently completed their new Masterpiece Pr-headphone amp, and I confess that I initially found the name of the product -- I don't know...perhaps just different from what I would have expected. However, this thing is staggeringly good, flawless, and probably the most transparent and musical component I have built or heard. A must hear, and an insane bargain if there ever was one.

A very talented designer. Over 20 years ago, I built his first published product - a dual output (high and low z), SRPP linestage that was published in Glass Audio (miss that publication, as well as Speaker Builder, very much!) All of this was prior to Transcendent Sound kit offerings. Bruce Rozenblit is of course most well-known for his OTLs, a couple of which I also own. Phenomenal amplifiers.

Yes, same bike - anniversary edition.

Agreed. I prefer to not break down speakers for parts, but I ended up with an assortment for various projects and experiments. Do I spot a 1200 GS in your avatar?!

Recently discovered that over the past fifteen years or so that I have gathered enough parts to build a complete pair of Heresies, the only remaining necessity being a second empty cabinet. Thus my interest. I would prefer something that does not need an inordinate amount of restoration - I have too many other amplifier and preamp builds and repairs to keep busy for some time to come. Thanks! erik

At the end of the day it really comes down to one's priorities, preferences, and so forth. I have never found myself aligned with instances on this and other audio forums where a member is told by others that he or she is wrong about what said he or she prefers as far as their chosen music reproducing machinery - that practice is nothing more than ludicrous. Amplifiers, just as many of the components used in their fabrication, can and do sound different. What makes one design "better" than another, at least as far as sonic attributes, is in my opinion most definitely related to the listener's/owner's/user's wishes and tastes as far as how they want the music they like in their listening space to sound. Of course there can be a consensus in groups about a preferred product (many of us really like Klipsch Heritage speakers), whether vacuum tubes, capacitors, resistors, inductors, amplifiers, crossovers, or guacamole. But what that consensus decides is limited to that group and certainly can't be applied universally as in something like "The five of us all thought Brand X (a great band IMO!) was by far the best of the bunch so it has to be the best for you too. I'm personally fine with a group consensus on something; it's the other part that doesn't work as well for me.

Wow, I haven't seen my version of Lessard's Horus (which as he designed it was/is already probably the very best single-ended 2a3 amp I have built or heard - and I have heard many. It's parallel-feed output topology is not new; in fact it's antique. But it is an extremely clever way to implement an output stage. I made a number of changes that suited what I particulalrly liked or wanted, but the essential platform is most certainly the Horus. A number of people had commented on the small size of the output transformers this type of amp uses -- thus judging them to be woefully inadequate in comparison to the more conventional single-ended OPT. An ill-informed interpretation at best, and a clear misunderstanding. My wife loved the amps. I still remember the first notes they played through the Klipschorns and she came upstairs and asked what amps I was using -- that the Klipschorns OR the Lowther horns with which they were sometimes used -- had never sounded so good. They are NOT inexpensive amplifiers to make, however. All this leads up to comparisons to the venerable single-ended EL-84 (a couple of which I have also made). Despite its high cost (including expensive passive components), the parafeed 2a3, as good as I think it is and in fact would love to build again, will be in tough competition with the incredible EL-84. In either single-ended or push-pull, it is among my favorite output valves. I completely rebuilt an old 1959 push-pull Leak that uses them, and it is a killer amplifier. I love it almost as much as my tiny EL-84 integrated.

Sifting through some of the chaff here, it seems there was at least one reference to the use of silicone rubber/sealant as one possible choice for reducing mechanical interaction and vibration between crossover components. Although I didn't own any Klipsch until we bought our first pair La Scalas in about 2002 (when I first started posting here under what at that time was a different handle), I began building speakers and crossovers around 1990. Back then, silicone was the go-to material -- preferred to hot glue and other gunk - for its adhesive qualities and flexible yet very tough vibration control. Crossovers have no interest in aesthetics, and I had never been able to perceive any sonic compromise between the somewhat-more-homely-looking chokes I wound myself and the exceedingly more expensive (not to mention decidedly more glamorous) air cores I sometimes bought when I was too lazy to play with enabled wire, but clear silicone (applied beneath, between, and around those caps, coils, and resistors) might be a bit easier on the eyes than some other options if "easier on the eyes" is important.

From what supplier/s are the boards sourced, and who is the manufacturer?

In one instance, the Ampsandsound website refers to its "design partners" for assistance in the development of one of its products. Circuit design is something that I find much more interesting than aesthetic implementation or outward appearance. Who are these "design partners" and with what specific aspect of design are they concerned? Certainly I'm familiar with Shannan Parks, and, even more so Alan Kimmel. Why was reference made to them here?