I may be hunted down and pummeled by big beast Krell owners for even suggesting this but I'm fast and packing:
What if a class D amp company offered their most powerful mono-blocks for free in-home auditions to owners of the huge,hot, heavy and electricity gulping Krell behemoths for fair and unbiased comparisons in their own systems?
Stereophile or The Absolute Sound magazine or even Audiogon could join the festivities, conduct the comparisons in an agreed upon method, ensure it's unbiased and report on the results as an ongoing magazine article or ongoing internet reports here on Audiogon.
I know, I know..... you're on your way once you grab your bazookas.
But please hear me out since it may be a win-win opportunity for Krell owners. Let's just compare D-Sonics top monos to what are the most powerful Krell mono amps ever made, The Krell Master Reference Monoblocks which are 1000 watts each, as one possible.scenario:
KRELL MASTER REF D-SONIC M3-1500-M
.NEW PRICE/PR $150,000 $2,750
AMP 683 POUNDS/EA. 11.5 POUNDS/EA.
POWER@8OHMS 1,000 WATTS 1,500 WATTS
POWER@4OHMS 2,000 WATTS 2,100 WATTS
AMP CLASS A D
IDLE WATTAGE 758 Kilowatts 13 watts
W X D X H HUMUNGOUS 7.25" X 15" X 4" SQUARED
Just a thought,
They have all bitten the dust due to the heat !!!!!
The big Krell amps are still out there. The owners are holding on to them because there is nothing new by Krell to replace them.
Most of the big krell's are either dead or still in use driving the out of production large panel speakers.Probably the same for levinson as well.
They become boat anchor because most owners find them too expensive to repair or rebuild. Others, pay up and keep them for bragging rights.
most keep them because they WORK well !
cap8 posts04-25-2017 6:14ammost keep them because they WORK well !
+1 on that cap.
If you go back a couple of years there were a glut of them on the used market, people started ditching them with the promise" of Class-D potentially turning them boat anchors, and vision of loosing a fist full of dollars, how quickly that turned around.
Now they are never seen on the used market and in there place come many of the high end Class-d’s being advertised used, and it’s no wonder once you’ve A/B them.
Every forum classifieds section seems to have a
Devialet Class-d or something similar for sale.
You can be relied upon as a good class D denier. You seem to post on any thread even mentioning class D. What’s the deal? Do you have a hidden agenda?
I think you’re doing a disservice to the many owners of hard to drive spkrs who drive them with very large, heavy, powerful, inefficient, hot running but great sounding amps like the big Krells.
All I’m suggesting is that anyone using one or more tube, class A or class A/B traditional linear amps should at least take a listen to one or more good quality class D amps in their system and decide for themselves. Many class D sellers offer free or low cost in-home trial periods on their amps knowing how few are actually returned to them.
This is what I did a few years ago to replace a large class A/B Aragon amp to drive my inefficient large panel Magnepans and I’m glad I gave class D a listen. I was very surprised to discover they outperformed my old amp in every area most of us care about; extremely quiet, highly detailed, life-like dynamics on source content that still has it, powerful well damped solid bass with a neutral mid-range and treble response that is only as sweet as the music source and upstream components allow.
Good class D amps also have non-sonic benefits: relatively affordable,small, light, efficient, reliable and mine never get hotter than luke-warm no matter how hard they’re driven.
I am not associated with producing, selling or in any other way associated with class D amps in any manner other than owning 2 very good stereo and a pair of mono-block examples of them. I’m just a big fan now and believe others are best served by hearing from a user who has no bias, agenda or stakes involved in this matter.
Big watts are unreliable due to heat. A friend used to own the larger FPBs and the amps showed leakage with the capacitors or some other components. The cost of maintenance may be high. Personally, I would not go higher than 200W for Class AB solid state amps. For higher power requirements perhaps look at some of the Class D options. Alternatively explore more efficient speakers.
"Big watts are unreliable due to heat."
Disagree. If properly and conservatively designed, hot running (class A) amps are very reliable.
Case in point, my Threshold SA6e’s from the early 90s are still running strong with never a fault. At 25 years of use, I replaced the power supply caps and rectifiers (both easily available from Mouser/DigiKey) as preventative measures. And still going strong.
Wow I'm very very sad i only have 350W channel oh well!!!
Wow!, Ridiculous!, I have a modified krell fpb 700cx, never runs hot because you have to use a single pole 30 amp breaker!, anyone who has a big krell that runs hot does not know what there doing!, as far as class d amp's, listened to many, still do not own one, and yes, I'm holding on to mine for sound reasons, my unit sounds a lot better than the stock 700cx 😉
They are few and far between. I purchased a pair of fpb-750mcx blocks thru Audiogon a year ago (there were 2 sets available at that time - both in Canada) to replace a KSA-300S that wasn't up to the task of being able to properly jam the bass panels on my bi-amped Apogee Divas. Each Krell has a dedicated 30amp wire; as do each of my Audio Research 610T's (upgraded to run KT120s), which run the highs and mids. Many probably scratch their noggins over having this much power on hand, but I suspect those folks haven't heard the magic of Divas when properly powered. My KSA-300S ran really hot and would actually throw its breaker...not surprising for what I was asking it to do. The 750s do NOT run super hot like that at all, but they are warm. Of course the tubes on the AR's are giving off considerable heat anyway. Luckily I have a separate Hvac system for my listening room, so it's not an issue for me. Zero complaints about the big Krells.
Guys, there will never be a better amp made, pound for pound, than the FPBcx series - 300, 400, and 600 WPC. There ARE some that occasionally hit the used market, though agreed considerably less often than even 3-5 years back. I nearly pulled the trigger on a 400cx within the past 6 months and chickened out - ONLY because of the "risk factor" of dealing with costly repairs that I presume WILL eventually be needed. I've been very lucky, knock wood, as a proud owner of a 300 FPB cx since 2001, and couldn't be happier.
Anyway, I also noticed a 600 FPBcx on the market within the last 6 years. Several in Europe as well but not practical. I love my Krell, and while I've considered jumping into some new power amp, I've decided it's just not sensible to move from known greatness to "who knows?" I'm holding onto it until it needs service. If and when that day comes I'll move to something else.
I was the biggest Krell fan and had 3 Krell amps purchased new, KSA100s, FPB 300 and FPB 600. They were great in the era but can't compete with current offerings. To tame the harsh and brightness, I always pair them with a tube preamp and MIT cables.
My 1st SS amp after Krell was a $5500 TRL Samson mono and it beats Krell in every area except for bass. No right or wrong but just my .02
audiolabyrinth4,242 posts04-28-2017 6:01pmWow!, Ridiculous!, I have a modified krell fpb 700cx, never runs hot because you have to use a single pole 30 amp breaker!, anyone who has a big krell that runs hot does not know what there doing!, as far as class d amp's, listened to many, still do not own one, and yes, I'm holding on to mine for sound reasons, my unit sounds a lot better than the stock 700cx 😉
Um... The 30 amp breaker has nothing to do with the operating temperature of the amp. Class A amps run hot because they're single ended, ie: output is always on. So, the heat is the result of the current running through the amp. It wouldn't matter if you had a 100 amp breaker (and hopefully the appropriate guage wire in the wall), the amp will still only use what it's going to draw. I'm assuming you've changed the wire to handle the 30 amp current?
I have owned several Krell Amps over the years and have never had an issue with any. My Fpb400cx Amps work wonderfully with my IRS Betas.
I like my older Mark Levinson 335 amp
I had a pair of MDA-300 amps that I bought new around 1990. They ran very warm, but never too hot to touch. They were recapped by Krell in 2005 and again in late 2016. They delivered very good sound and for over 25 years, I saw no need for any amplifier change. Following the latest recap, I decided that the resale value of my amps was at its max and I explored replacements.
I considered PS Audio BHK Signature monoblocks but didn't like the tubes; I liked the long Bryston warranty, but there were no local dealers for an audition; The Macintosh MC-475 sounded very nice at my local dealer but they seemed reluctant to let me borrow their demo for a weekend audition in my system, so it was scratched from my list.
I brought my local Krell dealer's DUO-300 home for a weekend trial. It delivered wonderful midrange and didn't exhibit the occasional higher frequency harshness that older Krell amps can have. Unfortunately the Duo-300 bottom end wasn't as fast and solid as the old amps. I spoke to my dealer and to Krell. They made a pair of Solo 575's available for me to try in my system. These new amps delivered the taught bottom end that the old amps delivered with a bigger midrange and the smooth high frequencies that I wanted. After 3 or 4 hours driving my Legacy Focus SE's as loud as I want them, the top of the new amps is not even warm to the touch and the fans do not appear to be running. The Solo 575's cost more than I had wanted to spend, but I bought them. It's been a few weeks, and I am still happy with this decision.
Hopefully the new amps will provide me with many years of reliable service. The new owner of my older amps has told me how pleased he is with them. I believe that he will also get many years of reliable service from them.
Later this year, I may bring home an Illusion II preamp to see how it compares to my recently recapped KRC-3. I'll be very surprised if it offers enough improvement to justify the cost.
<Krell dealer disclaimer>
Those who miss big Krells haven't heard the Solo 575 mono. frankgarufi is correct. The Solo 575 monos deliver it all, detail, speed, precision from top to bottom, and an enormous soundstage. When the Solo 575 monos became available, I compared them extensively to my demo pair of EV900e mono blocks. Yes the Solo 575s are half the price, and almost a third the weight, but they were immediately less harsh, less smeared, and the bass was much tighter and less "one-notey". The soundstage doubled in width and 50% in depth too. The Solo 575 mono is the best sounding Krell amp to date. Those who haven't heard them are in for a treat. They deliver over 600W into 8 ohms and over 900W into 4 ohms. While they don't double their output at every halving of impedance, they sound SO much better. Give them a listen. :-)
The last "big" Krell amplifier that I owned was
the MRA. I had four and Dan told me that I was
the only person in the world with 4 monoblocs.
I eventually returned to tubes--(4) VTL Wotans.
As to where did all the big Krell amps go, my guess is Asia.
Fabio, the model, has an impressive collection.
He never sold when he upgraded!
Tubejuckie64, I already had 10 gauge copper wire in attic that I installed, I installed the whole package myself, krell told me to do all this to run alot cooler and sound better, I complained about running hot with 20 amp breaker, talking about money well spent, the 20 amp breaker was chocking the life out of the amplifier literally!, this a very substantial up grade, I couldn't believe it, like a component change ,😎
Those MRAs had to be the most impressive amps ever put out. Huge but awesome. Personally don't care about class D although they are better than class A or A/B for guys with bad backs.
audiolabyrinth, I do agree that having greater supply can have an effect on the sound of the amp in that it can lessen the time required to recharge caps. I rewired demo rooms at a store I worked at years ago in order to accommodate the higher end amps we had and it did make a big difference in how they sounded. However, it doesn't make sense that having a greater electrical supply will lower the operating temperature. The heat is a result of current, therefore, the more current passing through the amp, the more heat created. It's no different than a burner on an electric stove - the more current you allow through, the greater the heat created.
Noble100 made an interesting point....MHO.....
Not so long ago, a bet was made that computer printers could be combined and made to add scan, copy, and fax functions. Don't know if anyone or any organization collected on that bet, but it's pretty obvious that we 'won' the benefits of it. That combination is pretty much the default now...
I don't have any doubts that class D will eventually match all existing classes in performance, even in the high power versions. This will take awhile yet...all advances generally do. These advances are usually driven by demand, the typical market forces that make up our civilization...whether we like that or not is more or less moot.
You want the class D of your dreams? Vote with your wallet. Buy what you perceive is the best of the current litter Now and start driving the technology of the future. That's what's drove the market to where it is now and it's still on the move.
Stop whining and wishing...get out, up, and help push.