Advice on Krell amplifier

I would have thought the dealer would have also recommended the Coda # 8 for the KEF Reference 5's.

The Krell would be the easy winner here.

Yyz-good suggestion. Actually, the Coda was recommended also but the Krell got even a higher recommendation. I haven’t heard or even seen either amp but was told that, while the Coda is very good and costs less, the Krell was even better particularly if looking for a tube like sound.  Any feedback?

@fast If I had a Paradigm Persona I think I would favor the Krell XD. I am actually considering that scenario for the Persona 9H for my downstairs. I wanted to put in a KEF Blade in that same space but may not be able to due to the side woofers. I will determine a solution to this issue later. Considering 9H, Blade (or KEF Ref 5's), and Thiel Cs 3.7 for this space.

I would not want too tubey sound with the KEF, but that is just my personal preference. So I do not think I would look at the Krell XD line for them. The only tubyish sounding amp I love is the Luxman m900u which for some reason I think would also be good with the KEFs.  If I were not set on the Luxman for my upstairs system I would want to try out the much cheaper Coda #8. My upstairs speakers will be Vivid Kaya 45 or 90 which sound very similar to KEF Reference.

I tend to favor the KEF's with more neutral sounding amps, such as Benchmark AHB2, Bryston, Wyred4Sound, and Hegel.  I am currently using a Peachtree Nova 150 with the KEF LS50's and though not as neutral sounding as the above mentioned I am enjoying the music.

Given the 2 choice you mentioned, I think I would look at the Coda #8  for the KEF over the Krell. I messaged 2 or 3 Coda #8 owners on A'gon in the past and their feedback was that they loved the Coda. One was using it with Persona 3F.

KEF Reference are awesome speakers so whatever amp you get for your 5's are likely going to be very satisfying for you.

I just went and re-read what I wrote. I never promised it would make any sense.

Tube like is a dubious term...some tube amps are great some not so much. Same is true for solid state and many other items. Tesla P100 range with a very heavy foot and winter weather is well under 100 miles...no one tells you that upfront!  You need to be able to use and enjoy what your have. I have a complete Krell system Evo 202,525av, 600 monos, lat 1s, vanguard with dac without amp using transparent reference cables and couldn’t be happier unless work allowed more time to use it and volume setting 7 out of 151 didn’t give my wife a migraine in a 6600 sq ft home. Would I buy it again no! It is complete overkill and useless in my home or outside a recording studio. The rare moments I can enjoy it are few and far between but very satisfying. Even the cabinet had to be custom...needed burl wood to match grass cloth wallpaper, be able to support hundreds of pounds of items and complex cooling system to deal with heat as well as custom electrical outlets to offer isolated ground with 20a individual circuits for nearly each item.  

At at least it looks great and will most likely end up in my office. 

The Krell would be the easy winner here.

+1 for the Krell, and it will drive anything now, or later you hook it up to.

Cheers George

I have used Krell Integrated amps for over 15 years in my two main stereo systems ( Krell KAV 400 xi and Krell S 550i). I have pushed Maggie’s with both integrated amps just fine and Maggies have to be the most inefficient speakers built. The sound I get is amazing - midrange, bass and imaging are the best I have heard. Just be aware Class A power runs hot! But it sounds great. Krell service was needed on my 550i and they were great! Go with Krell and you will be happy! I am!

I own the latest Krell Duo 300 XD and couldn’t be happier. I have owned the iconic 400 FPB and other Krell classics. This sounds the BEST. The latest series of KRELL XD amps are without question the best sounding amps on the market for the money. A thing of beauty given the relatively lower amount of power the amp consumes as a result of some brilliant software. Pure class A power has to be heard to be believed. 

I own the Krell 575  monoblocks, upgraded to XD. I can’t be happier with their new sound. Too, Krell’s customer service is amongst the best in the industry. 

I personally don't understand the use of burl wood to (match?) grass cloth wallpaper. I personally would have recommended bamboo. However, what do I know? I have only designed and built custom furniture for 40 years. I expect only a very few will understand and enjoy this post.

Some of the comments mention the older Krell Evolution line stuff (KAV 400 xi, S550i, 202, 525, 600, etc.).  These Evolution generation were a more transparent high resolution type of sound.

The new Krell stuff (Solo, Duo, XD) is the sliding-bias Class A and has a completely different sound.  It is a very smoothed over and possibly lush type of sound, which dealers can say "sound like tubes".  I disagree.  My opinion is that this is similar to a lot of the high bias bipolar Class A amps on the market (smooth, liquidy, lush).  Not bad, but a different type of sound.

The McIntosh MC312 is going to be more laid back and mild sounding (in a way) than the Krell XD, but it is going to be more neutral and natural sounding.  The Krell is likely to have more punch and impact.  But the McIntosh is very engaging even though it's mild/laid back.

There are three basic limitations implicit with all high-end class A power amps, so be certain that you're prepared to cope with the challenge that they present: (1) They're big, heavy beasts that generate a lot of heat, so the installation has to accommodate those needs. (2) Class A amps often use fans, and that noise can be intrusive unless there's enough isolation. (3) Minimizing DC offset at the amplifier output is a common problem with all solid-state class A designs. I'd prefer to see a published spec. limit on the maximum permissible DC offset. The Krell Duo 175XD on-line specs don't list any specification for that parameter, so be wary. I don't like to see any DC offset that exceeds 30mV, and 50mV would be the absolute worst case limit that I'd be willing to tolerate.

Numerous responders here are Krell amp. owners, so lets ask them to chime in…
Hey Krell guys, what DC offset do you read on your power amps? Simply read the DC voltage present at your amplifier's output terminals under a NO SIGNAL condition. (Use a DC multimeter capable of reading down to the 10mVdc or lower range. Place probes across amp output terminals or across load input terminals, whichever is easier. Be certain that you are on Vdc scale, not Vac.) Advise us of your measurement. And does your reading vary much when amp is cold versus right after a heavy listening session?

This DC offset is what your woofer will normally see in use, and it will cause the woofer to be offset from its optimal centered position by that voltage. (It's only the woofer that will see any offset because the crossover network capacitors in series with tweeters will block any such DC bias.)

Thanks vtvm. I’m the op. Never heard of DC offset until you brought it to my attention and I appreciate your help. Reading the Krell information on the amp (under circuitry), I found the following. Is it of any relevance...I don’t know enough to say:http://www.krellonline.com/stereo-amps.html

Last paragraph in the circuitry section.  

 Simply read the DC voltage present at your amplifier's output terminals under a NO SIGNAL condition.

Inputs should be shorted and not open circuit, or hooked up to a source, even if no music is playing, you don't know if any dc is coming from the source.
So best just to use input shorting rca's or xlr's, then measure the speaker terminals for any DC offset 0mv is naturally best but the amp would have to have a dc servo for this to be stable at 0mV, but < 10-20mV is fine for amp with no DC servos..

Cheers George

fast—Yes, the Krell info that you pointed me to is very pertinent; thanks.  And the DC servo correction that they cite should prove of material benefit in minimizing DC offset drift. As a consequence, I still don't comprehend why Krell doesn't publish a true spec limit for maximum DC offset, but I guess that's a separate issue. Regardless, I'd suggest making periodic measurements of DC offset to assure that it's within an acceptable margin during the first few weeks of operation. Measured results, when properly administered, provide the best evidence.

georgehifi—Yes, true. Most preamps (and signal sources) couple to the power amplifier's high impedance input through a coupling capacitor, thus blocking any DC input, but exceptions do exist. So if you don't know what your own setup does, then do assure a "no signal" test condition by selecting a shorted input.
Re. the 10-20mVdc range that you cite for acceptable DC offset…Yes, that's a tolerable offset range for a class A/B amplifier, but lots of class A power amplifiers typically exhibit greater DC offset. For example, the published spec limit for DC offset on many Pass power amps is 50mV, a value that I feel is marginal, at best. (But I applaud the fact that it's published! Of course, many buyers never read that deep.)