Power Amps with High Current or High Damping

A fellow Audiogoner and I have the same monitors. He's run into the same problem that I did when trying to fill a 14' x 35' room.

I found out, completely by accident, that when I replaced my Herron preamp and monoblocks (150 wpc) with a Karan integrated (170 wpc), the Karan solved the problem.

Though the wattage was similiar, the high current and/or damping factor of the Karan took a hold of the speakers and made them play whatever it was sending. The monitors are completely up to the task and never broke up.

Jim is trying to keep his cost for an amp that will control his monitors like this to around $3,000.00, give or take. He asked me about a McCormack DNA 225, but I don't know anything about McCormack amps.

I would like everyone's thoughts about the McCormack DNA 225 and suggestions for other amps that would fit the bill.

Can you tell us the speakers you are refering to?
Harmonic Precision Caravelles from Star Sound Technologies. You can see them if you look at my system photos.
For a few more bucks, I would look at a used DNA-500 over the DNA-250. In a whole different league, IMO. Its a pretty special amp and has been very well-reviewed. I am keeping mine for a future system. Its that good.
Krell_man, Hi Chuck the DNA-500 over the 250 would be the way to go for your friend.

I read some where that you changed from your Karan Integrated to a Burmester 036 Power Amp.

What differences did you find between the two.

You being a Karan owner, what are your over all thoughts regarding this product line as a whole. I'm looking at the 1200 mono blocks but the Burmester 911 MK3's and 909's are on my radar also which I would get two and run in monoblock config., speakers are MBL 101E's.
Dev, hey David, concerning the Karan versus the Burmester. The Karan KA I-180 is a hair darker than the Burmester 036.

That said though, Gary, the importer told me that the I-180 and S-180 sound a bit darker than any of the bigger power amps. I don't want to sound like I'm taking anything away from Karan, so I'd try to audition one in your system before taking my word for it. I haven't heard any of the Karans other than my KA I-180, but it was the best I'd ever had until I heard the Burmester.

I have heard the Burmester 036 and the 956 Mk 2, they have the same sound, just different power. I just happen to be one who's captivated by the Burmester sound. I'd definitely talk to Tonypdb1 since he's selling his 911 Mk 3's and running them with the MBL speakers.

Try Belles, 350A ref, 250 watts, and 2000 dampening factor, a real beast, very detail, great midrange and very powerful bass, one of the best amps all around:
Thanks Juancgenao. While I've never heard anything about the McCormack amp at all. I've never actually heard the Belles amp, but I've heard very good things about it.

So, as far as the damping factor:

McCormack amps - I can't find the damping factor

Belles 350A ref - 2,000 df

Karan KA I-180 - 1,200 df
Karan (bigger ones) - 6,000 df
Karan (biggest ones) - 10,000 df

Burmester 036 - 1,800 df
Burmester 956 Mk 2 - 2,000 df
Burmester 911 Mk 3 - 3,000 df

Krell_man, thanks for the info. I have already been in contact with Gary, great guy and I look forward to hearing the Karan gear in my set-up. Not knowing anything about the gear it's self it's always nice to get feedback from others like your self, it be good or bad. I didn't contact Tonypdp1 out of courtesy due to the fact that some don't like being contacted asking question specially when they are trying sell their gear off and it is apparent that he has now been trying for some time to do so including his MBL's. I would want to hear the Burmester in my system prior to purchasing along with purchasing them in away that I would have a warranty due to the fact of the cost factor, 2 amps big $$$ layout. Do you know Tony.

I have not actually seen the Burmester product in person but the pics I have seen the product sure looks like eye candy which is always a bonus.

I see you got rid of your AA gear and went with Wadia, was there a reason why you didn't move up the AA line. My current AA is the Hybrid Tube Dac which is a great pce paired up with the latest Oracle 2000 trans. via Stealth AES digital connection.

No, I don't know Tony. I just saw his ad.

I left the Accustic Arts digital for three reasons.

1. The man who upgraded my speakers and his partner suggested that I switch to the new Wadia 581 se, and then run it straight into a power amp. I have great respect for both of them, so I did it blindly. It's one of the best pieces of advice I've ever gotten.

2. Brian Ackerman told me that the jump from the DAC 1 Mk 3 to the Mk 4 was a really good jump, but the Mk 4 jump to the Tube DAC wasn't worth the extra $4,000.00 unless money was of no concern to me.

3. One AA transport, one AA DAC, one Stealth Varidig Sextet balanced digital cable and two Dream State power cords, that's $20,000.00. The Wadia 581 se and one Silent Source power cord, that's $10,500.00. And to me, the Wadia blows the AA pieces that I had, as good as the whole setup was, completely out of the water. You have to hear it to understand how much better the Wadia 581 se is, plus it can be upgraded to the 781 se (when the se model is released).

I didn't sell the Karan integrated because I wasn't happy with it, I just needed a really, really fast and good power amp to mate with the Wadia. I bought the Burmester for less than the Karan that's here on Audiogon. Either one would have been fine with me.

Damping factor is a highly over rated spec. Krell amps have low damping factors but no one considers them poor in regard to bass control. High current is a consideration.
What is an example of "high" current (spec-wise) vs. not?
I'd like to know if my amp is high current.
I think that you are onto the correct parameter but in an indirect sort of way. Damping factor, simplistically, is the ratio of (real part of the) speaker impedance to (the real part of the) amplifier output impedance. Remember that speaker impedance is variable over frequency so DF does not remain 1 fixed #. Unless the power amp output impedance is very low & well-controlled (sign of a robust power supply, which makes the amp cost sky-rocket), the amp output impedance is also variable over freq. So, you have both numr & denr varying over freq! Often you'll see lower DF as you come down in freq (often amp spec sheets show DF at 1KHz) that read in the range of just 10. So, the very large #s you have cited from spec sheets are essentially meaningless - they are probably measured with a non-reactive load (which is not what a loudspeaker is!).

I believe that you improved when you switched to the Karan amp is the amplifier output impedance - I get this feeling due to your comment "Karan took a hold of the speakers and made them play whatever it was sending". When the impedances are correct in the amp-speaker interface this is what the listener usually reports back.
One of the possible reasons for this is that the Karan amp has a much better power supply (lower impedance) & probably has more # of power transistors in the output stage (lower impedance) &/or higher current power transistors (more current delivery capability).
Krell_man, curious was there a reason you didn't try any other amps in the Karan line such as the stereo amp, KAS 270 Dual Mono stereo pce that has a damping factor of 6000 and 270 watts of power @ 8 ohms. There is another member "Cenline" who is also using the Wadia but with the Karan amp above and seems to be very happy.

Thanks for the info. I have never tried Wadia, will have to try as a friend just got the same pce you have recently but I have not made it over to his place as of yet.

Who is the man and partner you made reference to that you have great respect for?

Interesting regarding Brian's comments to you but I would have to disagree with him suggesting the Tube Dac improvement wasn't worth the added cost over the MK4, I feel it most defiantly is.

Brian doesn't sell "AA" product anymore correct?

That being said I would agree with you that the cost once you add up things is up there and if the Wadia is that good then it would most defiantly be a no brain-er.

Interesting info.
The ability to double an amps power as the impedence of a speaker is halved is an example of a high current amp.
High Damping factor is inherent in Icepower class D amps. My small Rowland 102 has DF=4000 at low frequencies and about 1000 at 1kHz. I said "inherent" because always two of four Mosfets are ON shorting load between power and GND. Feedback also helps a bit.

In traditional amps you can get high DF thru deep negative feedback which is really bad because of increased TIM distortions.

I believe that if you see spects like DF=5000 or THD=0.001% then something else has to give and it's usually the sound.

Very high DF is not needed since inductor in series with the woofer (about 0.08 Ohm) limits DF to about 100. At 20 kHz you'll get similar limitation by cable's inductive impedance.

Many people look at DF as a measure of the quality of the amp. I see DF as potential problem. Deep negative feedback caused TIM distortions make unpleasant sound (exaggerated odd harmonics) or even moments of silence after fast transitions (charge trapped at the output transistor's junction after saturation). This moment of silence is not audible (our brain fills the gap) but is fatiguing.
Whatever is going on here, damping factor (which is over-rated) has little to do with it. The speaker has a moderate impedance without a lot of phase shift- a tube amplifier as commented in the reviews can work with it just fine. In fact you don't need a lot of 'current'- you simply need the power to make it play since an 89 db efficiency is going to need some power behind it to make it play to convincing volume in a moderate (say 17'x25' room), depending on the program material.

So there is some difference between the two amps first mentioned that is not stated in the specs. It could be something as simple as reacting differently to the same speaker cable, which was not changed, at least so far as we know.
Hi Krell_man, this is a bit off the amp topic but I wanted to respond to your thread regarding the Wadia 581 SE vs "Accustic Arts" mainly because I was all excited after reading your thread.

So I contacted my friend and made a trip over to his place last nite for a listen.

He uses a pre now but originally had the Wadia connected direct to the amps as you currently do. He has Bryston 7 SST's mono's and Thiel 3.7's, he uses Elrod power cables.

1. My observation without getting into detail was the same as his, you really need a pre with this unit and that is why in the end he got one. The sound just does not compare without one.

2. I borrowed the unit, I hooked it up direct in my system. I then hooked it up with my pre. which in my opinion was much better but sorry it still does not compare to my current set-up, not even close.

I was all excited about this but in the end there was nothing I liked better period, if I had I would have commented. I fully understand your comments and reference made to the "AA" dac and transport you had, I fully understand the price difference with my current set-up also but honestly only one listen and the comparison conveys money well spent on my part.

My friend is actually going to be getting a 781 latest version to compare so he will let me know if it's worth the drive. My friend also heard my set-up during the comparison and mirrored my conclusions but of course it's allot more $$$$$$$$$.

He asked me to ask you if you can hear your unit running, I could hear his and during quiet passes this distracted me. I was told his first unit was much louder and took it back do to this for an exchange. I hear absolutely nothing with mine even with my ear right up close.

I currently have an Esoteric P01 unit with clock on loan but is just in the process of being broken-in, big! big! dollars and this thing is really noisy compared to mine, I had to put it in anther room as it was distracting me from my listening, what the heck is going on these should be silent.

For some reason, Wadia units take a few days to reach their characteristic sound. This has been commented upon extensively, and it includes everything in their line. I find a cold player to be unlistenable until at least 24 hours. Some claim it takes 7 days. Bottom line is that you should ask your friend to keep it in your system for a week without touching the power or interconnects. It may still not be your thing, but I think it is hard to do a quick A/B comparison.

The Esoteric P01 transport is a real statement piece.
Hi Rob,

thanks for that info. I still have the unit, it was plugged in at 8pm. I did do some initial listening but it was really scary unlistenable and did not mention that. My friend mentioned the unit needed some time, he came by the next day arround 6 pm. for a listen and this is the time frame of our evaluation, so aprox. 22 hours at that time. I'm not trying to suggest that the unit is not good but it just does not compare to my current set-up and the sound comparison of it being on it's own compared to being in the chain with a pre, well the later being by far my preference. I'm not being biased either because I would be the first to admit and would be looking at making changes, even if it was close I would but it's not. The unit is currently still in my system, luckily for me my friend has left it with me as he has gone away until next week. I had the unit playing all day, just back ground music but it's just not in the same league.

This Esoteric is the VU version with 8N copper wire set with clock and yes it's a real statement! never mind the suggest list!!!!!!!!!! Where the heck do I put all these pces. I have to say my expectations will be very high once I do my listening mainly do to the cost factor. I had a Metronome Kalista Ref Transport only in my system but prior to having the Tube dac, what a pce of eye candy. I did prefer it slightly over my Oracle trans but not by much, the deal breaker was that it would not play cds that I have never had issues with in the past nor currently which I factored in along with the list of over $50K compared to $7,500.00.

Have you got your pces back as of yet? waiting to read your thoughts regarding the Karan 1200's.

I'll be the first to say that the Wadia is not for everyone. I've never heard the 581, so I cannot speak to that. For me, an emotional connection with a piece of music requires a system to dig-deep into the recording and present all the information. This includes the musicians technique, the communication between the musicians, subtle alterations in tempo and dynamics, and the space which contains the musician, extending to the stage and the hall. There are CD players that may present a more pleasant or even intoxicating attack and decay of notes, and a more full harmony. The Wadia tells me whether the violinist is playing a Stradiverius, what part of the arms are pressing on the piano keys, how a soloist interacts with the conductor and orchestra in a concerto to create a searing performance. I have over a dozen recordings of Mahler 2, and I like to hear all the differences of each interpretation that go beyond 'a little faster in this movement', 'a little slower in that movement', and 'you can hear the clarinets more in that one'. There are pianists that create beauty from the inside purely from incredible technique, such as Moravec or Bolet. There are also great pianists that have such command of power and phrasing, they make a piece into their own, such as Richter and Horowitz. The Wadia tends to be of the former approach. Perhaps it is a bit more cerebral, but that is what gets me involved whether live or recorded. (BTW, I love Richter and Horowitz and many others, don't get me wrong!)

My DAC is still getting power updates and voltage output rewiring to better match the massive power of the Karans. It should be back together by the end of the month.