Mono blocked SET OTL rig - done at last!

Early B.

Blue -- what kind of music do you listen to?

madmax

He is a Blues man but seems to be open to anything!
madmax

unc2701

You know if those Cain's have any kind of correction circuit or is it straight amp->driver? I gotta say that is one sexy rig & I love the simplicity...

BlueMDPicker

unc2701: The Cains employ one full range Fostex Fe 166e per enclosure. The only other components in the enclosure are two runs of Cardas wire and two binding posts.

EarlyB: As madmax stated, I'm a blues man. But, I like absolutely anything that's well recorded.

Doro: It wasn't the soda. The magic mushrooms in the BBQ sauce made my dual Bose Airwaves appear to be SDA SRSs.

DAGLJAM6: Rozenblit's Grounded Grid preamp is very highly regarded. His book "Audio Reality" has the entire circuit layout for the enterprising DIY'er.

VR3

Are those Fostex's the rear-loaded horn?

I wonder how those compare with Early B's bookshelfs, since they are the same driver.

dorokusai

Do you read anything or just blurt out comments? He's expounded upon these speakers previously Mr Internet.

unc2701

http://www.madisound.com/pdf/fostex.pdf

full specs & prices on fostex drivers... Those cain's should sound better than any bookshelf with the same driver- the quarterwave pipe seriously increases the bass response over a sealed or vented box design.

Some designs put in a correction circuit to even out the impedence & high end response, but I guess Cain & Cain are of the opinion less is more- in the single driver world this seems to be the mantra.

BlueMDPicker

Originally posted by unc2701
... in the single driver world this seems to be the mantra.

In the SET and OTL worlds as well.

Terry Cain states he has tried several modified designs of the Abby enclosures over the years. I suspect he has experimented with correction circuitry along the way.

Regards,
Les Moore

audiobliss

Absolutely awesome rig!!! You've reached a level I didn't think was possible to reach! lol

jdhdiggs

There is definately some music I would love to here on that system.

Mike: Are you experimenting with different philosophies and setups throughout your home? Which rig do you enjoy the most?

BlueMDPicker

Much appreciated, audiobliss!

The goal I set out for with this configuration (unadulterated SQ) was pleasantly met -- if not exceeded. The system really draws you into the music with its pinpoint imaging, non-existant sound floor, and separation. The Fostex drivers, which BTW are really quite inexpensive, truly astound me with their speed and accuracy. For example, they can dig as low as a baritone sax can go while imaging a crystal clear ride cymbal at the same instant in time. The bass from the Abby enclosures is tight and alive. The mid range defies my description. And, while the 4 wpc won't lay your hair back (like the guy in the famous Maxell ad), it will produce well over 100 db at the listening position (12 feet) which is more than enough for my listening preferences.

Bruce, I think this post just became my review.

Enjoy the music, all!

Mike

Tour2ma

LOL.... I think so, too.

BlueMDPicker

James,

This is my first (at least by design) experiment with a totally new (to me) concept in audio. One might say I've come full circle -- from building kits by Heath and Allied in the '60s, through massive powered SS amplification in the '70s, tube/mosfet hybrids in the '80s and '90s, and back to modestly powered tube amplification today.

Someone once said (and I wish I could give them credit, but I believe it was Huxley) something along the line of "the more technologically advanced we become as a society, the easier it is to go backwards." Bruce Rozenblit's use of modern science to overcome the inherent faults of OTL amplification (heat, tube life, output stability) inspired me to take a few steps back. I'm very pleased with the results. Hands down, it's my favorite system to listen to.

I still love the sound of my SDA based rig with the Manley 75 wpc push-pull amp. And, in fact, it "fits" sonically much better in the lower level family room with lower ceilings and less side room opening intrusion. On the top level of our home, I have a Dynaco ST-70 running SDA 2As. My old friends, the Maggies, are still much respected and comprise a second listening experience driven by the tube/mosfet amp in the living room, with the SE OTL/single-driver rig. The only SS, 2CH rig I have left is a Nikko Alph 230 based system which drives the Atrium 45s on the deck very nicely.
I run a vintage Polk based HT rig in upstairs family room with a Denon AVR, and a Klipsch Reference Series based (with SVS for muscle) HT rig downstairs with an HK AVR. All this stuff really sort of fell together, although my wife claims I do nothing non-methodical.

Bring your music down and have a listen any time!

Mike

jdhdiggs

Thanks for the info. My life will be extremely crzy for the next couple of months but I'll let you know when things free up around here so that I can drop down to Ellicott.

I really like that minimalist approach, especially after seeing the ACA rigs. Something very refined about simplicity.

VR3

FYI - I read what he said, and my question remained...

How would these compare to the ones I built for Early B?

:rolleyes:

Thanks UNC!

organ

Originally posted by BlueMDPicker
Maurice,

Thanks!

In the traditional sense, a SET circuit uses a single output tube. However, this design employs several in parallel that act as one, to amplify both the positive and negative polarity portions of the music signal. In contrast, most amplifiers are configured so that the positive polarity of the signal is amplified by one output device and the negative polarity is amplified by another device -- or push-pull -- and the music signal is handed from one device to the other, and back again with each cycle of the frequency being amplified.

Mike

Thanks for clearing that up:). I hope to try a flea power amp one day but the ones I want are very expensive. First one I'd like to try is a SET using 300B output tubes. For now I'll just tube roll. Gonna buy me a quad of SED EL34 on the next pay check :cool: .

Maurice

BlueMDPicker

Let us know what you think of the SEDs, Maurice. Are you getting the cryoed ones?

organ

Mike,
Ordered mine from thetubestore.com they're not cryoed. I think it's all hype but can't really say that until I try them right?

I've been listening to them non stop since Mon.

First of all FORGET EVERYTHING I SAID ABOUT EL34'S PRIOR TO THIS POST! Here's the thing. As you know, I was using the 8 Ohm output taps on my amp until a few months ago. Switching to the 4 Ohm output taps made all the difference. So now, rolling output tubes is making a huge difference on my system. The difference is huge compared to rolling on the 8 Ohms output.

The SED basically destroyed EH. The sound is completely different. Some songs I've listened to countless times sounded strange until I got used to the new sound. The SED provided so much more refinement that my Klipsch comes close to the LSi9 when it comes to refined sound. Micro dynamics and overall dynamics is better behaved with SED. The bass and overall BlOoM is amazing. I'm telling you man, get a quad of SED for your Klipsch RF-3. They go together like peanut butter and jam. SED is laid back and very rich sounding which is perfect for the Klipsch.

This tube has class. By feeling and looking at it, construction and overall quality is superior to the other EL34 tubes I've tried.

Now I need to try the JJ E34L again. I accidentally mixed up my good quad with bad ones a few months ago and don't want to risk anything, so I'll buy another quad when I'm ready. I never got the chance to hear the JJ on the 4 Ohm taps.

Maurice