AXPONA 2012: Joseph Audio, Hegel, Channel D

I don’t think it’s a surprise that I think the Joseph Audio Pulsars are among the very, very best speakers, at any price. They do things that are just remarkable. And this year at AXPONA, things were mighty fine indeed. But please, don’t take my word for it. I’m a fan. Admittedly so. Do your disbelief a favor and find either a local dealer or attempt to get to one of the roaming audio shows and try it out for yourself. At $7,000 a pair, we’re talking a fair amount of coin, but but but …. In all honesty, this speaker falls on that part of the price-performance curve where you have to pay orders of magnitude more to get any discernible improvement.

Is it without flaw? Well, if you forgive it that it’s a monitor and not a floor standing speaker, and therefore won’t have subwoofer-style bass, then maybe it is. More importantly, it’s close enough that I no longer care.

But, if I had to nitpick … I think the Cardas binding posts are an unnecessary pain in the ass. I really prefer to use bananas on my speaker cables, but with these posts, bananas are forbidden. Which is annoying. The same posts were on my Merlins and I hated them there, too. If I ever manage to find the cash to order a pair, I’m gonna have to see if Jeff will replace them with some WBT binding posts or something. Either that, or I have order new cables. Which will be even more annoying.

Power came from a $5,800 200wpc Hegel H20 amp that was ignominiously dumped onto the middle of the floor.

I’ve not had a lot of experience with Hegel, though I do know a local dealer that carries the line, and the Joseph line, too, for that matter, though I’ve never heard them paired before. Hopefully, it won’t be the last time, either, because I think the two together worked quite the treat in this room.

On Day 1, tunes flowed directly from an Apogee DAC (below, next to the Mac Mini). I might have suggested to Jeff Joseph, who was sitting behind the audio wheel (that is, he was selecting tunes from Pure Music) that the Apogee might not have been the most … elegant …  DAC to put to use.

Wonderfully, I discovered that a Lynx DAC found its way into service for Day 2. The difference was eye-opening as the sound had significantly greater ease and extension and was far more in keeping with my previous experiences with the Pulsars. That is to say, it was astoundingly good.

Jeff ripped a couple of tracks from my memory stick and very kindly played back three. The first was a 24/96 rip from the recently re-released Smashing Pumpkins album, Gish. I think I lasted about 30 seconds before I leaned over to Jeff and asked him to skip forward. Damn track was a hot mess, still, even after remastering. Jeff’s comment: “I think they could have dubbed a few more guitars in there, don’t you?” Next up was the Wailing Jennies’ “The Devil’s Paintbrush Road”, off Firecracker. Outstanding! Love that tune and the harmonies are eerie and completely seductive. Last track was “The Lighthouse’s Tale” from Nickel Creek’s self titled debut. It made some guy cry. No, seriously! Some poor sap sitting in the sweet spot got all misty eyed while he sat there with his girlfriend. Don’t deny it, dude. You were totally busted! In defense of your utterly shattered manhood, it was a really sad song, and here on this system, it came out with an other-worldly beauty. It would have caught me by surprise, too, if I didn’t know what was coming. I mean, I wouldn’t have sobbed like a lost little girl or anything, but yeah, I felt it.

Channel D had some cool stuff on display, too, including a phono preamp, the $3,800 Seta Model L (for low output cartridges) for pulling and amplifying signal directly from an attached turntable and feeding it into an ADC (like the Apogee, which has excellent ADC capabilities), and from thence into a Mac Mini, running Channel D’s Pure Vinyl for applying the RIAA curves (and doing all manner of other goodness to it), before sending it back to a DAC for conversion, and then on to an amp (or preamp) and out to the speakers. Sounds like a convoluted path, no? Well, it is. But what you get is high-res, archival quality capture of your beloved vinyl collection. And that, my friends, may well be without price.

Something new! With computer audio, many folks are opting out from the dedicated preamp in favor of driving the amps from the DAC directly. Simpler circuit equals a better circuit, right? Well, not always. For those cases when the DAC has no analog volume control, but rather uses a digital volume control, you’re likely tossing out bits to control the volume — that’s how digital attenuation works. Call this bit-tossing “Problem #1”.

Your options? A passive attenuator! But … Well, not every DAC with a volume control is created equal. Even if that volume control is analog! Many DACs present a high output impedance (more than 100ohms or so), so they will not love driving a passive pre — or anything else, for that matter. Try it and the result will likely be harshness, congestion, and well, just crappy sound. Call this impedance mismatching “Problem #2”.

Channel D will soon be offering an alternative in the form of an ultra-low impedance SLA battery-driven buffer stage that provides stable, continuous discharge of voltage to the amp. No sags as voltage is pulled off the rails, here. No sir! And with it’s extremely high input (2Mohms) and very low output impedance (less than 36ohms), what it will get you is a happy amp — no more unpleasant edge, harshness or hotness — and no passive preamp required.

Problem #2? Solved.

The buffer will also provide much better gain matching. Not exactly a preamp, per se, but there is some flexibility as you can adjust the level of attenuation on offer: zero (or, “buffering”), -6, -12, -18, -24 and -30dB. What this gross-level of fixed attenuation provides is, well, a buffer. A buffer that will regulate the output of the DAC and allow you to match it to the sensitivity of your speakers. Got horns? Well, your DAC at zero attenuation will blast you out of the room. You’re going to have to turn it down — WAY down. Which mean bye-bye ton-o’-bits. Horns can play softly and sound great, but now, you’re feeding them a really butchered signal from that fancy DAC of yours. BUT! Using the buffer’s fixed-attenuation, say at either -24db or -30dB, means that you can safely use your DAC’s (or Pure Music’s) built-in digital volume controls and not have to toss out anywhere near so many useful, music-creating bits. Got a less sensitive speaker? No problem. Use a different attenuation level. Adjust to taste!

Problem #1? Solved.

The result? More music (literally!) — and better sounding music.

Charging is automatic. Stop playing for 20 minutes, and the system charges. Start playing, and it switches to discharge. Play time is something like 3 days. Quite a jam session!

Called the Seta BUF1, it will go on sale by the end of the summer and should fall around the $1,000 mark. Adjustable attenuation both balanced/XLR and single-ended/RCA for inputs and outputs are standard.

I’ve been using Rob Robinson’s marvelous Channel D’s Pure Music playback software for Mac for a year or so now. Like many, I consider it the standard for computer audio. It makes me chuckle a bit that Pure Vinyl is so popular given that I only got into vinyl after I got my start in computer audio (for me, CDs came “first”). But then, we all know that I’m weird. Of course, the audiophile old guard did this exactly the other way ’round, and for those of you that are looking for a way to protect the rather significant investment you might have in your vinyl collection, ripping those albums for computer playback means protecting and preserving that investment, and apparently, quite a lot of you agree.









About Scot Hull 1063 Articles
Scot started all this back in 2009. He is currently the Publisher here at PTA, the Publisher at The Occasional Magazine, and the Executive Producer at The Occasional Podcast. There are way too many words about him over on the Contributors page.

4 Comments

  1. I realize that, for many, the present audio world begins and ends (at a loss, in my opinion) with their computer; however, even without the computer onslaught, I’ve noticed for some time that, in many system reviews, the lowly cartridge and tonearm are often ignored. Possibly the turntable, due to it’s size and motion, gets a brief mention, but not always. So, echoing Jim Anderson, I’d only add that our Phantom tonearm was singing it’s heart out, along with the rest of the stuff; don’t forget, without SOME kind of analog front end, whether it’s a phono cartridge or a microphone, all the best amplifiers and speakers (and the digital interfaces) would be as silent as the grave….

  2. Agree with all your comments. I wasn’t the guy blubbering, but it could have easily been me. My wife and I thought this room and sound was one of the best. I’m personally looking forward to hooking up a similar system with the Pure Music for playback with Mac.

  3. Why did you omit the Hegel amp in your pics/write-up? The Heel amp is one of the best in it’s class.

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