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Florian
06-26-2012, 06:35 AM
Hello everyone,

i have not written in any forum in the last couple of years, besides as few one liners. This website seems to be more calmer now, maybe because i was gone :wink5: Age seems to be a good teacher, i even understand what RGA writes and can read it without busting a bubble, or two. Anyway i wanted to share my KRELL story with you guys.

As some of you may know, i am/was a hardcore Apogee Ribbon and Krell guy. For me, the two simply belonged together. One thing changed, the KRELL part. My first Krell AMP was a KSA150. It drove 1 ohm Apogee Scinitllas just fine but simply did not sound very good. I then got a KSA 100 MKII which was much better since it actually ran in Class A for more then the KSA150. Since that was not enough, i bought a KSA250 and thought this was just it.

But the sound was also cold, no micro dynamics, tone or instrument expansion. I sold it and got a pair of Sphinx Project 14 Hybrid amps (Tubes for the input and Mosfets at the Output) with no local or global feedback. This sounded very nice indeed! Problem was the DC offset, which is not compatible with actively run ribbons.

I found four Krell KRS200 mono block amplifiers, which are the largest mono blocks build by KRELL. I bought all four of them, but none of them actually worked. So i spend many thousands of to fix them. Once i got them all, they looked like this.

968 Pounds of amplification :out:

http://gallery.audioreview.com/data/audio/500/medium/DSC08394.jpg

The sound was "nice", you get impressed by the sheer size of them and the power consumption (1460 Watts) per piece, at IDLE.

I heard them for some month and thought that it was fairly good. In the end, the Apogees are with other systems the highest resolution speakers you can buy. Then came a moment were i heard a friends Apogee System which consisted of the Apogee Scintilla driven by LAMM 1.1 amplifiers (again Hybrids, no feedback). The sound was much better then the Grand with the KRS 200 amplifiers. :yes nod:

About a week or so i settled for the following amplifiers. 1 CAT JL2 Stereo Amp (187 Pounds) with 22 tubes and two NAT SE2SE mono blocks with 4x211 tubes and pre tubes. It sounds amazing! And so i thought id share that with you and upload some pics.

http://gallery.audioreview.com/data/audio/500/medium/DSC08618.jpg

My progress in the last few years were the visual restoration of my speakers. That was close to 10k... so it took some time. The electronics of the speaker should be finally done in 5 weeks (got a new tech that was man enough to touch it) :yes nod:

I thought that Apogees always needed Krells, but at least for my Apogee (Fully Active) 5ohm ribbons with aprox. 90db efficiency the Krells were completely useless. The NAT has 60 Watts of Single Ended Output power and massive output transformers. They drive the Apogees to very very loud levels with zero problems. I would never have believed it.... would i not have taken the risk. You learn something new everyday :-)

http://gallery.audioreview.com/data/audio/500/medium/DSC08587.JPG

Analog playback was introduced and many other things. The system now consists of the following:

CAT SL1 Signature Preamp
Monarchy Audio NM24 Tube Dac
Monarchy Audio DIP Combo
Olive Audio 4 HD
Watec Analog Drive 3
Watec Analog Acrylic Arm
Watec Analog Magnetic String Arm
Ortofon MC Rondo Red
Shure V15vXMR
Magnan Cables
Element Cables
4 Krell Monoblocks which are built into the speaker (going to throw out one pair for another set of NAT SE1 SE's

Cheers

Flo

bobsticks
06-26-2012, 06:49 AM
Hey Flo,

Damn that's a lot of steel...and not exactly an environmentally sound consumer solution :biggrin5:

I'm interested in what the NAT's bring to the table. We don't get too many of those around these parts thoug I know they are well-reviewed. Do you give up ultimate resolution for a more organic sound?

Btw, I love the refurb job on the Apogees---absolutely beautiful. Do you still run a lot of digital files? I ask only because getting to your components looks like a challenge.

Cheers,
M

Florian
06-26-2012, 07:02 AM
Hey Flo,

Damn that's a lot of steel...and not exactly an environmentally sound consumer solution :biggrin5:

I'm interested in what the NAT's bring to the table. We don't get too many of those around these parts thoug I know they are well-reviewed. Do you give up ultimate resolution for a more organic sound?

Btw, I love the refurb job on the Apogees---absolutely beautiful. Do you still run a lot of digital files? I ask only because getting to your components looks like a challenge.

Cheers,
M

Hi M,

it was definitely not a sound consumer solution, but neither is my car :mad5: To describe the NAT sound i must first comment on the CAT JL2 amplifier. That amplifier is very very good and i am safe to say it is amongst the best amplifiers one can buy. The NAT adds a bit on top of that! There is really no sacrifice in resolution, truth be told, the NAT or the CAT has many times the resolution, dynamics and frequency range of the Krell KRS 200s.

The NAT is very rare and i only found like one review. But a very good friend of mine recommended them based on their design. Single Ended, No Feedback, 211 Tubes and a massive output transformer. (They look small, but the speakers are quite large).

Thanks for commenting on the looks of the speaker, it was a complete pain in the ass. I had to personally disassemble them (1300lbs per side) with my neighbor and bring it to wood shops, car painters and more place. They even got all new Eichmann Terminals all around. (About 1500 Dollars for Terminals) :cry in:

I listen to 40% CD and 60% Vinyl... The Monarchy Audio DIP Combo generates a new clock and removes Jitter... Its a really great Digital Front End.... but Analog is better if the LP is good :p

Feanor
06-26-2012, 08:26 AM
Your systems is more spectacular than ever, Flo. :22:

I'm sure your buddy, morricab, would approve of the move to tube amps. Was he influential?

http://gallery.audioreview.com/data/audio/500/medium/DSC08618.jpg

What are those electrostatic/hybrid-looking speakers to the sides?

RGA
06-26-2012, 07:05 PM
That's a grand set-up for sure. Getting the Solid State out of there was a good idea. I've been saying it for years.

E-Stat
06-26-2012, 07:13 PM
About a week or so i settled for the following amplifiers. 1 CAT JL2 Stereo Amp (187 Pounds) with 22 tubes and two NAT SE2SE mono blocks with 4x211 tubes and pre tubes. It sounds amazing! And so i thought id share that with you and upload some pics.
Nice system evolution. I'm sure it sounds incredible with the tubes!

Florian
06-26-2012, 10:46 PM
Your systems is more spectacular than ever, Flo. :22:

I'm sure your buddy, morricab, would approve of the move to tube amps. Was he influential?

What are those electrostatic/hybrid-looking speakers to the sides?

Hello,

Brad (Morricab) was a very large influence. He recommended the NATs to me. We work in the same company in the same city, so we meet quite often for music, BBQ etc. Brad also never liked the Krell's.

Those speakers are a pair of Final 0.3 Electrostatic Hybrids i bought for a reason i don't remember. I sold them yesterday :22:

Florian
06-26-2012, 10:49 PM
That's a grand set-up for sure. Getting the Solid State out of there was a good idea. I've been saying it for years.

Very true, but it is hard to reset ones mind from all the forum, magazine and people talk. And when you look at close to 1000 pounds of amplifiers then it is intimidating and fascinating. But if you are truly honest with yourself, then it simply doesn't cut the cake.

Florian
06-26-2012, 10:51 PM
Nice system evolution. I'm sure it sounds incredible with the tubes!

Hello,

yes indeed it does. But they are not less expensive than the Krells. There are 16x 6550 tubes in the CAT plus 6 tubes in the line stage. The CAT preamp has 10 tubes (5 for the line input) and (5 for the phono). The NM24 DAC uses 4 tubes plus the 4x211 tubes in the NAT excluding 4 tubes in the line stage.

Potentially this can be very costly as the 6550 and 211's are not exactly cheap.

But the music is very good indeed :14:

RGA
06-27-2012, 01:50 AM
I think we all learn the lesson that more weight - BIG and more power, or NEW technology isn't better. It can be better but it still amazes me that old designs like tubes reign supreme and indeed, if you and brad are any indication then not only do tubes reign supreme with High Efficiency loudspeakers but they ALSO kick butt on very hard to drive loudspeakers as well.

I am hoping to get an electrostatic in around September for review. We'll see. The small space may be an issue but reading some websites they claim their stats will be perfectly fine in small rooms.

Oh and by the way - FWIW - the new amps LOOK WAAAAAAAAAAAAAAAAAAAAAAAAAAAAAY better than those butt fugly Krells. And that may not count for much but it counts.

Florian
06-27-2012, 04:08 AM
I agree on both the looks and the indication. Things that i have learned from Brad which seem to be key are the following technical aspects:

* No feedback (local or global)
* Single Ended
* Massive power and output transformers

When it comes to panels, there are really a few important things to know. Apogees are basicaly large resistors. Their impedance is low but not fluctuate more than 1 ohm across their range. Newer Apogees (DIVA, Duetta Sig.) or in very rare cases the Grand (only 7 pairs so not really worth to talk about) have about 5 ohms and in the highish 80's db efficiency. Because the impedance does not fluctuate its much easier on the amp as one might think.

Electrostatics vary in their resistance a lot and need very capable amps. Its a natural match for tubes since solid state amps have no idea what to do with a 600 ohm load. My setup is special in the sense that its about 90 db in efficiency and 5 ohm stable and the amplifiers are (when electronics are done) connected directly to the ribbon. No passive components and limited amplified range. Thats why a potent tube amp has no problems with it :-)

** I love the glowing at night :-)

E-Stat
06-27-2012, 05:16 AM
There are 16x 6550 tubes in the CAT plus 6 tubes in the line stage....Potentially this can be very costly as the 6550 and 211's are not exactly cheap.
Tell me about it. I've been feeding the VTLs with the same number of outputs for ten years now.


But the music is very good indeed :14:
That's the point!

bobsticks
06-27-2012, 06:00 AM
Thanks for commenting on the looks of the speaker, it was a complete pain in the ass. I had to personally disassemble them (1300lbs per side) with my neighbor and bring it to wood shops, car painters and more place. They even got all new Eichmann Terminals all around. (About 1500 Dollars for Terminals) :cry in:


It was definetely worth your time. They're quite breathtaking.

GMichael
06-27-2012, 06:08 AM
It all looks just so incredible. I can't imagine what the sound quality must be like. Congrats Flo. Great job!

Florian
06-28-2012, 02:30 AM
Thanks a lot you guys :14:

JoeE SP9
06-28-2012, 06:18 AM
You're looking real good there Flo! Welcome to the "glass" side!

tube fan
06-28-2012, 08:26 AM
I think we all learn the lesson that more weight - BIG and more power, or NEW technology isn't better. It can be better but it still amazes me that old designs like tubes reign supreme and indeed, if you and brad are any indication then not only do tubes reign supreme with High Efficiency loudspeakers but they ALSO kick butt on very hard to drive loudspeakers as well.

I am hoping to get an electrostatic in around September for review. We'll see. The small space may be an issue but reading some websites they claim their stats will be perfectly fine in small rooms.

Oh and by the way - FWIW - the new amps LOOK WAAAAAAAAAAAAAAAAAAAAAAAAAAAAAY better than those butt fugly Krells. And that may not count for much but it counts.

The King electrostatic speaker impressed my at the 2010 CAS. It was driven by tubes, and lacked very little. Three-dimensionality was among the best I have ever heard.

Florian
06-28-2012, 11:49 PM
You're looking real good there Flo! Welcome to the "glass" side!

Thanks Joe, i have been on the "glass" side with the preamp for a while. Many things changed but the CAT always stayed. My main mp for listening has been the SET amp (NAT SE2SE) and its wonderful. :D