McIntosh MC275 CLS and Krell

[edwinr]

Perhaps someone could explain to me how an amp could improve the base response in Summits. I would think with it's onboard amp that your systems amp would not have much, if any, affect on base response.

With pleasure...

While the Summits have onboard amplifiers, they are only as good as the signal fed to them. This is not something I have read about. This is something I have worked out for myself by listening to my speakers driven by various power amplifiers, both tube and s/s. So if the power amplifier has some 'tonal character', or has limited bandwidth then the result will be an accurate reproduction of that signal by the Summits onboard amplifiers - albeit 'tailored' by the crossover to roll smoothly off above 250Hz...

 

[nsgarch]

What I can say about the Pass Labs, is the AMAZING ability to reproduce the VERY low bass frequencies the Summits are capable of.

Edwin, neither the Pass or any other external amp one selects to drive the Summit (or Vantage) has any effect on those speakers' bass performance. Their woofers are completely under the control of the speakers' built-in Class D ss amp(s). The bass portion (under 270Hz) of the signal from your Pass amp isn't driving anything. A circuit inside the speaker is simply sampling (or 'listening in' ) to the bass frequencies (under 270Hz) and sending them to the inputs of the built-in woofer amps.

I should also mention that it's very important to balance the gain of the internal ss bass amps, with the gain of your external amp. In the case of a pair of MC275's for example, you need only 'crack' the bass level controls open a small amount, about 60 deg. Then, when you increase the preamp volume control to normal listening level, the woofers will transition seamlessly to the panel without 'swallowing' the mids/highs. (Maybe that's the part you guys have been missing?)

As a matter of fact, when I went to Phoenix to hear the Summits with a pair of 275's, the very first thing I did (as the owner, Mike Ware looked on apprehensively ) was to go behind the speakers and turn the level controls from almost full open, down to about a quarter open. I then walked over to the preamp and smiling at Mike said "Now this is how you get good bass." and I proceeded to turn up the volume control. I only wish I had a picture of the grin on his face!

 

[edwinr]

BUT.... the Summit's onboard digital amps need to sample something nice. Which is a full bandwidth signal. I know my power amplifier isn't driiving anything below 270Hz per se, but they are providing the highest quality signal for my Summit's internal amplifiers to drive the 10 inch woofers.

If I insert a less capable power amplifier into my system, I can hear the bass quality and extension suffer. By comparison by inserting my Pass Labs or my older Mark Levinson, the bass extension and quality improves - significantly. In the case of the Pass Labs amplifier, the improvement is quite profound. :music:

I am open to other comments or correction of course. This has just been an opinion formed from experimentation during the last few months.

 

[mosttoysrk]

I am perplexed. How could changing speaker cables have wrought such a difference? I know in some very good systems upgrading cables can help to fine-tune or tweak a system. But wresting such a dramatic change is puzzling. Maybe changing the speaker cables coincided with the amplifier having completed a settling in period - or something..

Edwinr,
I failed to include a connection difference with the 2nd audition of the MC275 to my CLS's. My MIT speaker cable is biwire after a junction box and I only connected the mid/high end cable to the CLS's and not the bass cable. I use the spade connection to the cls screw terminal and then the 2nd part of the cable I have spade/banana plug adapters that I plug into the CLS.
A little embarrassed to mention that part. After extended listening periods I am enjoying the Mac and now starting to think about tube rolling... arghhhh. Neil has pointed me to an auction with Purist cables, but I just mentally have a hard time pulling the trigger on a 1100.00 set of speaker cables, and my wife wants diamond earrings for xmas this year.... maybe I can sneak by with new cables for me and zirconium earrings for her...:devil:

 

[GregLett]

Edwinr,
but I just mentally have a hard time pulling the trigger on a 1100.00 set of speaker cables, and my wife wants diamond earrings for xmas this year.... maybe I can sneak by with new cables for me and zirconium earrings for her...:devil:

:devil: :devil: :devil: Go for the cables and the zirconium earrings

 

[nsgarch]

an audition

I'm going to email Roger Sanders to request an in home audition of a pair of his ESL speaker cables, to compare with my Purist Venustas. I'll let you all know if he accepts

 

[edwinr]

:devil: :devil: :devil: Go for the cables and the zirconium earrings

Okay: We have a conundrum. I agree go the cables and the earings. But are we talking about 'zirconium' as in the stuff used in nuclear reactors, or 'cubic zirconia' commonly synthesized into diamonds? Either might be entirely suitable as a gift for the wife. So here we go...

Zirconium (pronounced /zɚˈkoʊniəm/, /ˌzɝˈkoʊniəm/) is a chemical element that has the symbol Zr and has the atomic number 40. A lustrous, very corrosion resistant, gray-white, strong transition metal that resembles titanium, zirconium is obtained mainly from the mineral zircon. Zirconium is primarily used in nuclear reactors, especially in the cladding of the fuel rods, due to its low neutron-capture cross-section and its resistance to corrosion.

Cubic zirconia (or CZ), the cubic crystalline form of zirconium dioxide (ZrO2), is a mineral that is widely synthesized for use as a diamond simulant. The synthesized material is hard, optically flawless and usually colorless, but may be made in a variety of different colors. It should not be confused with zircon, which is a zirconium silicate (ZrSiO4). Cubic zirconia is extremely rare in nature.

It's Sunday morning here in Australia. I've been up all night with sick kids and it's now my chance to throw the baby to the dingos...

 

[edwinr]

Edwinr,
I failed to include a connection difference with the 2nd audition of the MC275 to my CLS's...

Thanks for that extra info. I was puzzled. There had to be more to the story...

 

[mosttoysrk]

Edwinr,
I stand corrected on the cubic zirconia..... I was kind of close.

 

[nsgarch]

Clarity (and I don't mean the speaker ;--)

In case there's nothing good on TV tonight, here is a much more understandable summary of what I've been feebly trying to explain about the proper nutrition (power) for ESL's. Why they need voltage, not current, why watts isn't watts, etc:
http://www.sanderssoundsystems.com/ESL Amp White Paper.htm

And here is an explanation of what attributes make for a good solid state ESL amplifier:
http://www.sanderssoundsystems.com/ESL Amp White Paper.htm

 

[tonepub]

As a matter of fact, when I went to Phoenix to hear the Summits with a pair of 275's, the very first thing I did (as the owner, Mike Ware looked on apprehensively ) was to go behind the speakers and turn the level controls from almost full open, down to about a quarter open. I then walked over to the preamp and smiling at Mike said "Now this is how you get good bass." and I proceeded to turn up the volume control. I only wish I had a picture of the grin on his face!

If you set the 25 and 50hz level controls to to about a quarter open, they would both be set at about -8db. How would that provide "good bass"?

Once again you are making it up as you go....

Adjusting these controls arbitrarily without a set of test tones and a meter is pretty pointless. It will vary from room to room.

 

[nsgarch]

If you set the 25 and 50hz level controls to to about a quarter open, they would both be set at about -8db. How would that provide "good bass"?

I thought it was clear what I meant by "good bass" was bass in balance with the mids/highs. If the gain of the Summit's internal bass amps sufficiently exceed the gain of the mid/high (external) amp, the speaker will be bass-heavy at any volume. Anyone who has bi-amped a speaker using different external amps (e.g. tube top, ss bottom) has had to address this issue. It would be nice if ML had put a gain attenuator ahead of the 25/50 Hz contour controls, like they do on their subwoofers, but it can still be done with the contour controls pretty well since there are two of them.

Once again you are making it up as you go....

LOL! That's certainly the pot calling the kettle black!

Adjusting these controls arbitrarily without a set of test tones and a meter is pretty pointless. It will vary from room to room.

No, it's actually more efficient to make such rough adjustments by ear. And it's an excellent way to learn how rooms can "sound". Later, one can use test sweeps to fine-tune contour settings and plan room treatments if necessary.

I hope you appreciate my taking the time to explain many things it took me years to learn. I could just blow you off, but I sense you really want to understand how the hip bone came to be connected to the thigh bone. I remember all the great people who pointed me toward experiences where they knew I'd learn the good stuff, the truth. Unfortunately, that was then and this is 2007. So don't be surprised if you get a bill

 

[tonepub]

No, it's actually more efficient to make such rough adjustments by ear. And it's an excellent way to learn how rooms can "sound". Later, one can use test sweeps to fine-tune contour settings and plan room treatments if necessary.

I hope you appreciate my taking the time to explain many things it took me years to learn. I could just blow you off, but I sense you really want to understand how the hip bone came to be connected to the thigh bone. I remember all the great people who pointed me toward experiences where they knew I'd learn the good stuff, the truth. Unfortunately, that was then and this is 2007. So don't be surprised if you get a bill

You keep missing the point Neil, your explanations rarely make sense and rarely if ever have any science behind them. So, I'm not learning anything from you, other than the fact that you are terribly dogmatic.

I hate to break the news to you, but Ive spent just as much time with this stuff as you have, if not more. I do this for a living, 10 hours a day and in addition to having a couple of scientists on the staff, have access to the best and brightest in the industry any time I want to pick up the phone.

All I really ever get from you is that the gear you have and the way you do things is the best and only way to do it. And anyone that dares question you gets the major condescending attitude.

Sorry, I'm not impressed.

And for what it's worth, I got taught how to set my Summits up from the factory, so I think they had a bit more insight on how to set them up than you do...

 

[nsgarch]

your explanations rarely make sense

Well, not to you, perhaps. One of my best friends was chief design engineer at Wadia. We talk often, and he thinks I make perfect sense; and is quite comfortable with my understanding of the science behind what I've learned.

and rarely if ever have any science behind them.

That's a bold statement. MIT must have made a horrible mistake in issuing me a degree. Did you pick up the phone and have one of your scientists verify that assertion?

So, I'm not learning anything from you, other than the fact that you are terribly dogmatic.

I've helped people set up audio and video systems far different from mine in every way. They always seem satisfied with the results. People who are threatened, rather than excited by those more knowledgable, often describe their perceived oppressors as 'dogmatic'; yet they often turn out to be dilettantes, too lazy to actually learn anything. So why should I care?

I hate to break the news to you, but I've spent just as much time with this stuff as you have, if not more.

That doesn't necessarily mean you've learned as much as I. And judging from your website photo, you would therefore have been about six years old when you became interested in audio?

I do this for a living, 10 hours a day

You sell advertising, publish a magazine, take great product photos and write music reviews for a living. And you're very good at it from what I can tell. Do your readers expect you to be all that, and an authority on audio to boot!? They expect too much!

and in addition to having a couple of scientists on the staff, have access to the best and brightest in the industry any time I want to pick up the phone.

I see, so you are knowledgable by association?

All I really ever get from you is that the gear you have and the way you do things is the best and only way to do it. And anyone that dares question you gets the major condescending attitude.

I didn't mean for you to feel threatened or become so defensive. I guess I should leave you alone, or you might want to hurt me :bowdown:

 

[kwr]

Hi guys,

We are speaking of a difference in observation regarding high end audio systems here??? Nobody has died ..... yet.

Pax

Kevin

 

[twich54]

Neil and Jeff, Keep the personal "banter" Crap off the forum. The spirited dialouge that this thread started with was good and I too enjoyed it, but there is no need to elevate to the level it is now.

As we say in the railroad biz....get the rerailers out and put 'er back on track !!

 

[C.A.P]

Man , What a pompous attitude you do have. Excuse us for being so stupid and having our own opinions. This I can tell you MIT must not have had any communication classes. I never met a smart man who had to prove it! If you are some audio wizard ,and you know circuit design and set up . WHY DON'T YOU HAVE YOUR OWN COMPANY ! So the world will actually KNOW how smart
you are.

Please stop pushing your rubbish opinions on us and your little quotes and articles to prove your beliefs. Your starting to sound like a Robert Harley.

They are biased and opinionated!!!!!!!!!!

I didn't go to Harvard or MIT or any Superior educational facility. However; I did learn early on in audio, that its not always a one way street of dead science. My 25 years in it has shown me that, and humbled me a few times. Science and conventional thinking will kill a system sometimes. Sometimes its fool heartedness and luck that we stumble upon that really makes them shine.

Tubes are for some and SS are for others. As for the Summit's . The best amp will only compete with a class D amp at best. Match me a good class D amp to a good Class A amp and tell me if there is a difference. I am not knocking the Summit. But I still stand by my theory that a non powered Summit with a External x-over would blow away a powered version with the right amps

 

[nsgarch]

Astrology anyone?

When 'happy accidents' occur in technology, and they do all the time, there is a scientific basis for them nonetheless. There are three perfectly acceptable responses to 'happy accidents': Some want to discover the science behind it, so they can repeat it. Others understand there is an explanation, but don't need to know it. And there are those who believe it a one time event that can't be explained (a miracle.)

As a scientist, I need to know why; yet I'm comfortable with those who for a variety of reasons, decide they don't. Many of those people actually respect the ones who've made the effort to investigate and learn; often paying for their services. For example. having someone like Richard Bird (Rives) configure their listening room.

As an artist, I can also accept the miraculous, when the science required to explain something doesn't yet exist. History has shown that one day it will. How many 'miracles' have been explained in our own lifetime? DNA anyone?

What makes me angry, are the pundits whose utterances imply that their anecdotal experience and speculative conclusions represent some kind of self-evident 'truth': "While the 275 is not the greatest match for the current ML-s, it is quite nice with the CLS". Gosh, if I didn't understand all the other possible reasons for that individual's negative experience, why would I even bother to give the MC275 a listen for myself? That's why I consider such off-the-cuff remarks, especially from some in this industry, to be irresponsible, misleading, and ultimately damaging.

On another subject: Roger Sanders has generously offered to let me evaluate his ESL speaker cable. He also offered (I didn't ask) to send me his new ESL amplifier to audition. How could I refuse? I'll describe my setup and procedure in detail, so it's easier for others to spot any flaw(s) in my investigative technique. A sloppy reviewer I'm not! (Rigorous experimental technique is something schools like MIT teach until they're second nature, and insist they be followed.) I'll report back when the dust settles.

 

[GregLett]

When 'happy accidents' occur in technology, and they do all the time, there is a scientific basis for them nonetheless. There are three perfectly acceptable responses to 'happy accidents': Some want to discover the science behind it, so they can repeat it. Others understand there is an explanation, but don't need to know it. And there are those who believe it a one time event that can't be explained (a miracle.)

As a scientist, I need to know why; yet I'm comfortable with those who for a variety of reasons. decide they don't. Many of those people actually respect the ones who've made the effort to investigate and learn; often paying for their services, for example having someone like Richard Bird (Rives) configure their listening room.

As an artist, I can also accept the miraculous, when the science required to explain something doesn't yet exist. History has shown that one day it will. How many 'miracles' have been explained in our own lifetime? DNA anyone?

What makes me angry, are the pundits whose utterances imply that their anecdotal experience and speculative conclusions represent some kind of self-evident 'truth': "While the 275 is not the greatest match for the current ML-s, it is quite nice with the CLS." Gosh, if I didn't understand all the other possible reasons, such as flaws in the setup, for that individual's negative experience, why would I even bother to give the MC275 a listen for myself? That's why I consider such off-the-cuff remarks, especially from some in this industry, to be irresponsible, misleading, and ultimately damaging.

On another subject, Roger Sanders has generously offered to let me evaluate his ESL speaker cable. He also offered (I didn't ask) to send me his new ESL amplifier to audition. How could I refuse? I'll describe my setup and procedure in detail, in case anyone notices a flaw(s) in my investigative technique. (Rigorous experimental technique is something schools like MIT teach, and insist upon.) I'll report back when the dust settles.

I am interested in hearing you results on the ESl amp.

 

[GregLett]

When 'happy accidents' occur in technology, and they do all the time, there is a scientific basis for them nonetheless. There are three perfectly acceptable responses to 'happy accidents': Some want to discover the science behind it, so they can repeat it. Others understand there is an explanation, but don't need to know it. And there are those who believe it a one time event that can't be explained (a miracle.)

As a scientist, I need to know why; yet I'm comfortable with those who for a variety of reasons. decide they don't. Many of those people actually respect the ones who've made the effort to investigate and learn; often paying for their services, for example having someone like Richard Bird (Rives) configure their listening room.

As an artist, I can also accept the miraculous, when the science required to explain something doesn't yet exist. History has shown that one day it will. How many 'miracles' have been explained in our own lifetime? DNA anyone?

What makes me angry, are the pundits whose utterances imply that their anecdotal experience and speculative conclusions represent some kind of self-evident 'truth': "While the 275 is not the greatest match for the current ML-s, it is quite nice with the CLS." Gosh, if I didn't understand all the other possible reasons, such as flaws in the setup, for that individual's negative experience, why would I even bother to give the MC275 a listen for myself? That's why I consider such off-the-cuff remarks, especially from some in this industry, to be irresponsible, misleading, and ultimately damaging.

On another subject, Roger Sanders has generously offered to let me evaluate his ESL speaker cable. He also offered (I didn't ask) to send me his new ESL amplifier to audition. How could I refuse? I'll describe my setup and procedure in detail, in case anyone notices a flaw(s) in my investigative technique. (Rigorous experimental technique is something schools like MIT teach, and insist upon.) I'll report back when the dust settles.

I'm interested in reading your results on the ESL amp.