Krell Saga

[mep]

The only tube amp I ever owned that came close to sounding like it had the sheer power of the Krell was my Quicksilver MS-190 amps (with triode boards). Too bad the MS-190s were designed around the original Mullard EL-34 which was renowned for how far it exceeded the design maximum specifications of the EL-34 tube. And Mike designed the MS-190 to take the EL-34 right to its hairy limits of 25 watt plate dissipation. Modern EL-34s just don’t take kindly to this punishment and can’t stand up to the heat (literally). I would still own these amps if suitable new production tubes were available. I also owned the Quicksilver V4 amps and sold them because they didn’t have the dynamic slam that the MS-190 did nor did they have the overall beauty. For the here and now, I’m happy with the KSA-250.

 

[MylesBAstor]

Wattpower like horsepower can be addicting,someday I will get my tube amps running,but I'm not rushed.

It's not what the additional power does; it's what it doesn't do And now, in contrast to the early days of high-end, have high powered amps that sound as good as their lower powered brethren

 

[mep]

It's not what the additional power does; it's what it doesn't do

Like clip every two seconds...

 

[Orb]

I remember those heat sinks getting darn hot-enough to scramble some eggs on

Got to love current bias, as long as it is not in the summer

Mep,
which do you think is the better value in terms of sound quality and preference; the amp or pre or both equal?
Early days so appreciate this is jumping the gun a bit, but I assume you are starting to form an opinion on the two now you have been able to listen to them a little bit.

Thanks
Orb

 

[mep]

Tough question Orb. If I had to pick just one, I would probably go with the preamp. I think it represents crazy good value in the land of high-priced preamps and I believe it would elevate the sound of many systems. The build quality is something to be seen as well.

And having said that, I really wouldn’t want to be forced to choose between the two if I had to give one up. These two pieces belong together just like two pieces of a puzzle that snap together. The KSA-250 seems to be grounded to the center of the earth with the way it exerts control over your system. I don’t think there are tons of amps available at any price that can do everything the KSA-250 can in terms of power/current output into low impedances which helps make it unflappable.

 

[Orb]

Thanks Mep and adds to the consideration of them being a great purchase.
Funny and also shame that while the KSA over here in UK seems to have a legendary status the preamp stayed under the radar in comparison, looking at what you have been posting they are well matched as a pair.

Thanks and really enjoying reading your story with the Krells so far.
Orb

 

[mep]

Orb-I’m pretty sure the KBL was designed to go with the KSA-250. They were both made at the same time, and really, there wasn’t that much of a price difference between the two pieces when they were new which says something about the preamp. Another thing that I think isn’t well known about the KBL is the fact that it was designed so that you could buy two of them and run them together as not only dual mono, but fully balanced as well. There are internal dip switches that have to be set in order to convert each preamp into a mono fully balanced preamp. I wonder if anyone ever bought two KBLs and ran them that way? I would love to hear from anyone who has.

 

[microstrip]

Thanks Mep and adds to the consideration of them being a great purchase.
Funny and also shame that while the KSA over here in UK seems to have a legendary status the preamp stayed under the radar in comparison, looking at what you have been posting they are well matched as a pair.

Thanks and really enjoying reading your story with the Krells so far.
Orb

Orb,
The KBL was a fabulous preamplifier, but its reign was disturbed by the appearance of the KRC. I have owned both, and IMHO the KRC was a better preamplifier, even when used with the KSA 150 - at that time I did not own or have access to a KSA250. It is matter of preference, as both were very good units, but I found that the KRC was more detailed and dynamic that the KBL. Others will think differently.

 

[Steve Williams]

Orb,
The KBL was a fabulous preamplifier, but its reign was disturbed by the appearance of the KRC. I have owned both, and IMHO the KRC was a better preamplifier, even when used with the KSA 150 - at that time I did not own or have access to a KSA250. It is matter of preference, as both were very good units, but I found that the KRC was more detailed and dynamic that the KBL. Others will think differently.

I agree

I owned the KBL, KRC and the KRC-HR and IMO they were all terrific but the KRC-HR was a masterpiece

 

[microstrip]

I agree

I owned the KBL, KRC and the KRC-HR and IMO they were all terrific but the KRC-HR was a masterpiece

Steve,
I should have referred it - my last KRC was the KRC-HR model and my comments apply to this version.

 

[mep]

Micro-Didn't you tell me that the ARC LS-2 sounded better than the KBL preamp? Does that hold true for the KRC-HR too? The ARC LS-17 couldn't touch the KBL.

 

[microstrip]

Micro-Didn't you tell me that the ARC LS-2 sounded better than the KBL preamp? Does that hold true for the KRC-HR too? The ARC LS-17 couldn't touch the KBL.

Mep,

Yes, the LS2 sounded better than the KBL when using Sonus Faber Extrema's with the typical sources used twenty years ago. IMHO all opinions about "better" or "not better" must be considered in a particular system - extrapolations must be considered with great reserve and care. The ARC LS2 had a balanced solid stated buffer after the tube gain stage and perhaps was a better match for the old Krells than current ARC preamplifiers. But in any case the KRC-HR was in a different class.

Although used prices do not indicate sound quality, the Audiogon average used price for KRC-HR is almost three times that of the KBL.

 

[Steve Williams]

Fortunately there was a painless pathway to upgrade from the KRC to the KRC-HR

 

[mep]

Mep,

Yes, the LS2 sounded better than the KBL when using Sonus Faber Extrema's with the typical sources used twenty years ago. IMHO all opinions about "better" or "not better" must be considered in a particular system - extrapolations must be considered with great reserve and care. The ARC LS2 had a balanced solid stated buffer after the tube gain stage and perhaps was a better match for the old Krells than current ARC preamplifiers. But in any case the KRC-HR was in a different class.

Although used prices do not indicate sound quality, the Audiogon average used price for KRC-HR is almost three time that of the KBL.

So the KRC-HR goes for around $3K?

 

[Steve Williams]

So the KRC-HR goes for around $3K?

Mark

If it does, and you like the Krell sound I would grab one

 

[microstrip]

Fortunately there was a painless pathway to upgrade from the KRC to the KRC-HR

Yes, as far as I remember they replaced the Penny and Gilles potentiometer and step motor with a relay based discrete resistor attenuator that could fit in the same space.

 

[Steve Williams]

Yes, as far as I remember they replaced the Penny and Gilles potentiometer and step motor with a relay based discrete resistor attenuator that could fit in the same space.

and IIRC it wasn't a terribly expensive upgrade

 

[mep]

I just read the review of the KRC-HR on Stereophile that was written by Wes Phillips back in 1996. Wes starts off gushing about how great it sounds, but then at the end of the review he says there is no depth of image and layering of people on the soundstage. The CJ Premier 14 sounded better to Wes. Oh, and the Premier 14 was just as quiet as the KRC-HR (rather, Wes actually stated that the Krell was as quiet as the CJ!) and the CJ had just as good bass as the Krell.

 

[microstrip]

I just read the review of the KRC-HR on Stereophile that was written by Wes Phillips back in 1996. Wes starts off gushing about how great it sounds, but then at the end of the review he says there is no depth of image and layering of people on the soundstage. The CJ Premier 14 sounded better to Wes. Oh, and the Premier 14 was just as quiet as the KRC-HR (rather, Wes actually stated that the Krell was as quiet as the CJ!) and the CJ had just as good bass as the Krell.

I still own a cj premier 14. While the layering capabilities of the cj preamplifier and depth of stage of the premier 14 driving Krell amplifiers (the KSA 100s and 300s) were better than any Krell preamplifier (and most of the competition, BTW) the bass of the KRC was better than that of the tubed preamplifier.
The premier 14 is however a less neutral preamplifier - but a friend of mine who has been using it prefers it to the more neutral ARC LS2, as it has more "slam" and "drive" at medium volume levels. And yes, the premier 14 is not a noisy preamplifier compared to typical tube preamplifiers.
I repeat myself - I would guess that in the described 1996 reference system using Krell digital and Theta ProBasic III the cj tubed preamplifier would easily win!

 

[mep]

Time for an update. As some of you may have seen from some of my other posts, I’m having a hum/buzz issue with the KSA-250 amp. You hear it through the speakers, the level doesn’t change with volume, and it’s always there. It is fairly low in level, but since my room is so quiet, it still annoys me. It has raised the noise floor of my system which is the exact opposite of where I’m trying to take my system.

Ray who is in charge of repairs at Krell says it sounds like the power transformer is starved for current. Ray was supposed to send me a Krell 20A power cord when they returned the amp to me and they forgot. The PC I’m using now is made by PS Audio and I don’t like the way it fits into the Krell IEC connector. It sags. I doubt this is the problem though, but we will see when the new PC arrives from Krell. Meanwhile back at the ranch, Joe Abrams has kindly offered to lend me an MIT Z-Trap which Joe thinks will solve the problem. We shall see.

In the meantime, I’ve decided to remove the KSA-250 from service and revert back to my pair of Phase Linear 400 Series 2 amps. They are stone-cold silent and my noise floor is super low with them in the signal chain. They also have a bit more air on top than the KSA-250 and might be a little quicker on their feet. If you believe in the concept of speed, the PLs are speed monsters. The bottom line is that no matter how much I like the sound of the KSA-250, I’m just not willing to put up with the noise it’s adding to my system. Even though you can’t hear it when music is playing, you know it’s there so that means it’s playing with your mind while it’s playing music.

If I can’t solve the hum/buzz issue, the Krell KSA-250 is getting kicked to the curb. The ironic thing is that I moved to SS in order to free myself up from the issues of dealing with vacuum tubes. None of the tube amps I have owned over the years has ever had any type of hum/buzz. They were all dead quiet.

I know some people shudder when I say I’m listening to a pair of PL 400 Series 2 amps, but if you shudder, I promise you that you have never really heard them. I haven’t owned any “super amps,” but I damn sure have owned some great sounding ones. Some of the amps I have owned are the ARC D-76, ARC D-76A, ARC D-79, ARC D-70 MKII, ARC VT-100 MKII, Quicksilver Audio V4s, Quicksilver MS-190s with triode input boards, and once upon a long time ago, a Dynaco ST-70. I can tell you that the PL amps hold their own and then some. I’m bumming that my KSA-250 makes noise, but I’m not bumming that I had to go back to the PLs.