Just sold my Krell 2 channel amps and looking for a 5.1 amp now.

What do you guys think about a used Dreadnaught 1, $1.5K more for a Dreadnaught 2, Krell TAS or do you guys have any suggestion about $3K 5.1 amp?

Do you mean 5CH amp or are you going to be running your sub off of the amp as well?

Do you mean 5CH amp or are you going to be running your sub off of the amp as well?

No, I've a powered sub therefore just a 5CH will do it.

I would stay away from theta amps since they do not measure well on the bench. What speakers are you using?

Martin Logans. Rally I thought they are well make just like the CBIII :p

Martin Logans. Rally I thought they are well make just like the CBIII

Which logans, you will want an amp that can drive a low ohm rating of 1 ohm or less.

I would stay away from theta amps since they do not measure well on the bench.

coldmachine is right: you truly are an idiot....

coldmachine is right: you truly are an idiot....

More name calling? You should look at the stereophile reviews and how poorly the theta amps tested, we already had a thread on this.

http://www.avsforum.com/avs-vb/showthread.php?t=1086966&highlight=theta

Citadel rated 400 watts into 8ohms, achieved only 250 watts into 8 ohms before clipping@ $15,800/retail is pretty ridiculous IMO. Intrepid had to be "relaxed" to 2% THD, before it achieved 100 watts into 8 ohms. See a pattern here?

Starting at post 14.

You should look at the stereophile reviews and how poorly the theta amps tested, we already had a thread on this.

You seem to have some fixation with condemning and passing judgment on audio equipment that you've never heard, based on things or bench measurements you've read, or just whatever unfounded and uninformed prejudices you cling to.

Good for you - then don't buy them.

But most people here want to make intelligent and informed decisions, and are looking for helpful input. Your constant shrill bashing of stuff you've never heard is, again to quote coldmachine, "almost universally despised."

Your constant shrill bashing of stuff you've never heard is, again to quote coldmachine, "almost universally despised."

I find he often brings up things others overlook in their rush to love a product.

I find he often brings up things others overlook in their rush to love a product.

Rushing, whether to love or hate, is usually not the best approach.
And fine: if above he wanted to point out some info re. bench tests or w/e for someone to look into, that would be helpful. But telling someone to "stay away" from it is completely different.

Well, technically, he said "I would stay away" and why. That is somewhat different from telling someone what they should or shouldn't do.

In any case, I don't have a problem with Doug as he's not the kind to engage in personal attacks and can have a reasonable discussion with others who are reasonable. I've had plenty of disagreements with him and it was never contentious because I respect his opinion and you get as you give.

hlkc, If it helps any I'm quite happy with a CB III, DN I, B&W 801 Matrix 3 and HTM-3 combination. No idea how the B&W's would compare to Martin Logan though.

Cary Cinema 5 - $2500 used / $5000 new ---- 200 wpc x 5 in 8 ohms (may struggle with challanging speaker loads 2-3 ohms)

Parasound HALO A51 - $2000 used / $4000 new ---- 250 wpc x 5 in 8 ohms

Sunfire TGA5400 - $2200 used / no longer made ---- 400 wpc x 5 in 8 ohms

The Theta DNII is good amp but if you are going to dump that type of cake ($) look at the BAT 6200 as well. Another consideration is the SimAudio Moon line. Can't recall the model number but they used to (I'd guess still do) make a beast of a 5 channel amp.

Now (shameless plug) take a good long look at pro or commercial amps. I run the Face Audio F1200TS (3 = 6 channels, only use 5, 600 wpc in 8 ohms) and you can get these new for less than the used counterparts above.

Now (shameless plug) take a good long look at pro or commercial amps. I run the Face Audio F1200TS (3 = 6 channels, only use 5, 600 wpc in 8 ohms) and you can get these new for less than the used counterparts above.

Don't get me wrong, it's a worthwhile recommendation or "(shameless plug)" :), it's just that to me, I consider Face as more of a "counterpart" to the Class H Emotiva or QSC amps then to any of the others mentioned.

I just think it's only fair to at least mention the class distinction when describing different types of amps. Even though you did characterize it fairly as pro or commercial, that may not always mean Class H.
Maybe I've just read way to many DW posts today and the nitpicking is wearing on me.

hlkc

The Wyred4sound D Class ICEPOWER Monoblocks seem to be making alot of folks happy around here these days too and run $1,200 each for 570w out @8ohms. There's a long thread on them around though I admit no personal experience.
Various used Levinsons, my personal favorites, will also come in at around your price range. I think you have a ton of options.

Yep the FACE is class H (something to do with constant demand on the voltage rails but I'm sure I'm wrong). BOB LEE of QSC could expound in greater detail because I got this feeling he is lurking... :D

Though I've not heard the WYRED4SOUND amps I did have one of the first PS Audio GCAMC products which Cullen Circuits (aka W4S) helped design and manufacture for PS Audio. It was a great amp. I had it matched up with Martin Logan Summits, Klipsch RC-7 center and RS7 surrounds (yep not the greatest combo but in two channel those Logans were quite nice).

At that time I thought the ICE module was a bit thin in the high end but adequate non the less. All in all another good amp, W4S or PSA.

The KRELL TAS, part of the OP's thread title, is another good product. The local dealer is a friend and he had this amp on demo and in his home with good results. My mom's eye doctor a few years ago invited me over for a listen and I was impressed. Not sure of what they are selling for these days but KRELL did/does make some nice amps if you got the wallet.

hlkc, If it helps any I'm quite happy with a CB III, DN I, B&W 801 Matrix 3 and HTM-3 combination. No idea how the B&W's would compare to Martin Logan though.

hlkc

The Wyred4sound D Class ICEPOWER Monoblocks seem to be making alot of folks happy around here these days too and run $1,200 each for 570w out @8ohms. There's a long thread on them around though I admit no personal experience.
Various used Levinsons, my personal favorites, will also come in at around your price range. I think you have a ton of options.

Les Auber and bigbrother52,

Thanks for the info and I am looking into it now. I am waiting to upgrade my CBIII to HDMI and that's why I am considering DN1 or DN2 now.

hlkc, which amps did you just sell? As you know the krell will take the load of the logans no problem.

hlkc, which amps did you just sell? As you know the krell will take the load of the logans no problem.

KSA 200S. It is a fantastic amp for my CBII before, CBIII and Integra 9.8 today while I am waiting the HDMI upgrade. I can't tell you how much I love it. I am just try to consolidate 3 amps, 1 Krell monoblock for center, KSA 200S for stereo listening and movie L&R and KSA 500 4 channels for rest of the 4 channels to 1 amp such as DN1, DN2 or TAS now.

I find he often brings up things others overlook in their rush to love a product.

Thanks, and since we are talking about amps I think measurements should be at the top of the list. When we see companies like theta out right lie about what their amps can and can't do I think it is very important to bring up.

In any case, I don't have a problem with Doug as he's not the kind to engage in personal attacks and can have a reasonable discussion with others who are reasonable. I've had plenty of disagreements with him and it was never contentious because I respect his opinion and you get as you give.

one thing we have in common is NAD, now when are the new HD processors coming out?

The KRELL TAS, part of the OP's thread title, is another good product. The local dealer is a friend and he had this amp on demo and in his home with good results. My mom's eye doctor a few years ago invited me over for a listen and I was impressed. Not sure of what they are selling for these days but KRELL did/does make some nice amps if you got the wallet.

After the krell being made in china scandle are you sure you want to mention their name? Was it the 300i or something, anyways not saying made in china is bad but why pay the premium?

And fine: if above he wanted to point out some info re. bench tests or w/e for someone to look into, that would be helpful. But telling someone to "stay away" from it is completely different.

Amplifiers that use little or no global negative feedback typically don't measure as well as ones that do. For example BAT make the BAT6200 which applies the same philosophy. I do not know if they still do but BAT made an amplifier for Integra. I remember that BAT had to make a negative feedback design, against their philosophy, so that the specs would be better for the Integra even though sonically the Integra is an inferior amp to the BAT6200. The BAT6200 is one of the most highly regarded as well as the Theta Dreadnaught multi-channel amps that has been made. Call BAT and ask which amp they thinks sounds best;), the low priced Integra they made or the BAT6200 which cost multiples more. Ayre amps also use the same design philosophy which should be no surprise since Charles Hansen did the vast majority of the design of the Dreadnaught. Ayre amps are also highly regarded but likely don't measure as well as negative feedback designs either. Simply looking at specs solely is simplistic. It's how you think that there is a such thing as a true 32 bit dac and actually post a thread about it. That was very telling.

Amplifiers that use little or no global negative feedback typically don't measure as well as ones that do. For example BAT make the BAT6200 which applies the same philosophy. I do not know if they still do but BAT made an amplifier for Integra. I remember that BAT had to make a negative feedback design, against their philosophy, so that the specs would be better for the Integra even though sonically the Integra is an inferior amp to the BAT6200. The BAT6200 is one of the most highly regarded as well as the Theta Dreadnaught multi-channel amps that has been made.

No and this is just an excuse for the theta amps, unless you like your amps to oscillate and start blowing out drivers. Why would adding a "global negative feedback" cause a loss in sound quality?

Call BAT and ask which amp they thinks sounds best, the low priced Integra they made or the BAT6200 which cost multiples more.

What does price have to do with what and amp can and can't do?

Simply looking at specs solely is simplistic.

So if someone bought the theta amp and needed the advertised 400 watts power to drive their speakers to the volume level that was needed what would happen when the theta amps can only supply 250 or less?

Bulldogger, roger that. Cranking in lots of feedback seems to be an easy way of getting measurements but when abused sure sucks the life out of music. Wonder if it's one of those time domain things that usually aren't measured?

Amplifiers that use little or no global negative feedback typically don't measure as well as ones that do. For example BAT make the BAT6200 which applies the same philosophy. I do not know if they still do but BAT made an amplifier for Integra. I remember that BAT had to make a negative feedback design, against their philosophy, so that the specs would be better for the Integra even though sonically the Integra is an inferior amp to the BAT6200. The BAT6200 is one of the most highly regarded as well as the Theta Dreadnaught multi-channel amps that has been made. Call BAT and ask which amp they thinks sounds best;), the low priced Integra they made or the BAT6200 which cost multiples more. Ayre amps also use the same design philosophy which should be no surprise since Charles Hansen did the vast majority of the design of the Dreadnaught. Ayre amps are also highly regarded but likely don't measure as well as negative feedback designs either. Simply looking at specs solely is simplistic. It's how you think that there is a such thing as a true 32 bit dac and actually post a thread about it. That was very telling.

That was why in this thread, aside from Mr. Winsor's impeccable history of saying the most ignorant and ludicrous things (as he masterfully demonstrates for us in this thread as well), I said it was purely idiotic to pass judgement on an amp based solely on reading its bench measurements. Measurements are only one part of the equation, and can often be either relatively insignificant, or as you pointed out, misleading in terms of how an amp actually sounds. Yes, Mr. Winsor: some of us actually listen to audio equipment to decide whether or not we like it!!

Krell amps have eliminated global negative feedback and only use the smallest amount of local nested feedback. I absolutely love Krell amps (even despite Mr. Winsor's 1,000th repetition here of his famous Krell/China rant). And Krell's THD numbers suck - who cares?

BTW: please clarify it wasn't me who started the 32-bit DAC thread... :cool:

That was why in this thread, aside from Mr. Winsor's impeccable history of saying the most ignorant and ludicrous things (as he masterfully demonstrates for us in this thread as well), I said it was purely idiotic to pass judgement on an amp based solely on reading its bench measurements. Measurements are only one part of the equation, and can often be either relatively insignificant, or as you pointed out, misleading in terms of how an amp actually sounds. Yes, Mr. Winsor: some of us actually listen to audio equipment to decide whether or not we like it!!

You did not answer any of my questions? So what if someone bought the theta citadel and needed 350 watts to run their system to its desired listening levels?

BTW: please clarify it wasn't me who started the 32-bit DAC thread...

There are a number of companies that make 32 bit DAC's now.

my opinion after a extensive listening test between the krell tas,sim audio titan and bryston(14bsst..2ch only) with krell resolution 2 speakers and later b&w 802 and later my own DIY(Volt 12" woofers,ATC mids and SS tweeters),i picked the Titan,because i live in Canada,if i lived in the USA it would have been TAS,they were that close..the ATC mids had a bad reaction with the Bryston..but the bass was great,but bryston sounds perfect with the PMC line.
the tas was great and you can bridge the 4 channels,flexable,i like that.
john

I have gone round and round with HiFi gear for decades now. I have owned lot of stuff from McIntosh, Anthem, Meridian, Lexicon, Coda, Krell, Bryston, Theta and have demoed even more in my own system. From my experience, and to my dismay, you just can’t judge something until you actually hear it for yourself, and when possible, in your own system.

Being an obsessive analytical guy, I used to require some sort of quantitative improvement before considering a change. Like Doug does, this means relying on published and/or tested specification numbers. Over time I can’t figure out how to make any of these numbers correlate with what I hear from my ears.

In college (Lehigh University) I had a Hafler amp powering my Magnapan speakers. I offered to sell the amp to my fraternity (I wanted to upgrade to the bigger Hafler…yes – it started that early for me:o). I was chastised for wanting to sell them a mere 110 w/ch amp. I think they called it a boat anchor at the time and accused me of trying to rip them off for my own gain (pre-AudiogoN/eBay days). Instead, the more technically savvy electrical engineers in the house poured over the specs on lots of units and had them buy some monster 500+ w/ch receiver instead. Within one hour of the first party with the new receiver it was fried. The guy in charge of the purchase brought down his personal receiver which also blew in short order. So I brought down my Hafler and its accompanying pre-amp (both were home built), and the combo easily survived the night as well as many subsequent years of service for me.

Over time, this sort of experience has occurred more often than not. The Hafler’s numbers weren’t impressive compared to the cheap receiver’s numbers. It makes this hobby a PIA in a way because I cannot evaluate squat from a piece of paper, which constantly makes you (me) wonder what to change next. For years now I only change things if I can hear an improvement in my room. Then there’s the whole cable argument which make less than zero sense to me, but my ears don’t lie – especially PCs (cables - another source of frustration for me:mad:.

I am sorry Mr. Windsor, but IMHO you need to actually hear something before discrediting it altogether, or even making a comment on it. You are obviously well entitled to your opinion. Perhaps it is not really what you say, but how you say it that matters. If you are relying on Stereophile tests some years ago I am afraid you seem naïve to me. I wonder how folks explain tube gear’s specs, which often aren’t mind blowing.

There is one thing I can say to the OP for certain though – the Krell will likely drive anything. The Theta might not drive everything, but definitely has its strengths regardless of the numbers. I have owned Krell (FBP/TAS). I have since replaced it with Theta (Enterprise/Dreadnaught). I like the significant improvement I realized in my system. I know this improvement would not have been possible with my previous speakers – I know this because I tried it back then too. Just my experience…call it synergy maybe…

I know I'll get flamed for this - whatever - I am in this for fun, this is as agry as I'll get - I won't respond to a flame - time to go listen...

Sorry for the length.

Theta Citadel 1.5s got me off the merry go round. I have had quite the array of amps over the years (Pass, Krell, Rowland, McCormack, BAT, VAC, DarTZeel) and I love the Citadels the best overall. Enjoy Dave.

Why would adding a "global negative feedback" cause a loss in sound quality?
It has been said that global negative feedback can lead to less stability, harder clipping, and increase in higher order harmonics (which tend to be more annoying than low order). They also go the opposite of the design of triode tube-based amps which many people like (i.e. local feedback only).

That is not to say that eliminating global feedback automatically makes an amp sound better. In any topology, excellent skill is required to make a good sounding amp.

Amir:

You lapsed into pronouns without making clear definitions... That's almost as bad as lapsing into acronyms without first defining them ;) We've both worked at acronym generating businesses so you know exactly what I'm talking about :D

I think what you're trying to say is that Solid State Amps which utilize (high amounts) of global negative feedback tend to have a THD profile favoring higher-ordered harmonics (which are more dissonant). Whereas SS amps with minimal or only local loop negative feedback tend to have a THD profile favoring lower-ordered harmonics which are more consonant with the input.

THD profiles favoring lower ordered harmonics are also typically found in tube based amplifiers.

Cheers,

I would consider "lower ordered" harmonics to be 2-4th order, which corresponds to ratios of 2:1 (an octave), 3:2 (a perfect fifth) and 4:3 (a perfect fourth). Going beyond that you get into some fairly dissonant intervals quite rapidly. Some not as bad as others. Major and minor thirds thirds, and major and minor 6ths aren't "terrible" but are still dissonant by definition.

If you studied music, you'll understand the terms consonant and dissonant intervals.

It does all tie together and a perfect device in the reproduction signal chain would add no distortion at all. They only exist in theory, not at all in practice.

It is important to differentiate between the recording and reproduction chains as the goal is to recreate the recorded performance with high fidelity. If not, it wouldn't be HiFi, would it? :D

Amir:

You lapsed into pronouns without making clear definitions...

After spending three days posting on jitter, I wasn't about to jump right into this argument with both feet. But couldn't resist at least stating the argument :).

After spending three days posting on jitter, I wasn't about to jump right into this argument with both feet. But couldn't resist at least stating the argument :).

Oh don't disagree with your argument, just helping the details get fleshed out -- and you know exactly why :D

While I'll probably hate myself for rejoining in this a perfect illustration of how massive amounts of global feedback can create rather non-musical results is the mass market transistor receivers in the '70s and '80s. Remarkably low THD and other measured specs were achieved but in general they sounded rather dreadful in comparison to the other gear of the time. Much like Dave's Hafler vs the 500 watt 'monster' amp.

Oh don't disagree with your argument, just helping the details get fleshed out -- and you know exactly why :D
Oh, I didn't think you disagreed. But thought were pretty brave to dig into reasons why! :)

It has been said that global negative feedback can lead to less stability, harder clipping, and increase in higher order harmonics (which tend to be more annoying than low order). They also go the opposite of the design of triode tube-based amps which many people like (i.e. local feedback only).

That is not to say that eliminating global feedback automatically makes an amp sound better. In any topology, excellent skill is required to make a good sounding amp.

Who says this? If it has a negative impact it can be measured.

Who says this? If it has a negative impact it can be measured.
Why do you post on the Ultra Hi-End HT Gear ($20,000) Forum? You don't own a high-end home theater; you don't aspire to own a high-end home theater; you can't afford a high-end home theater; you have never actually heard any high-end equipment; you constantly bash high-end equipment and tell people not to buy it; and all you want to do is hijack the threads and argue about measurements. Please let us enjoy this forum by limiting your postings exclusively to other forums. We would all be grateful if you did.

Why do you post on the Ultra Hi-End HT Gear ($20,000) Forum? You don't own a high-end home theater; you don't aspire to own a high-end home theater; you can't afford a high-end home theater; you have never actually heard any high-end equipment; you constantly bash high-end equipment and tell people not to buy it; and all you want to do is hijack the threads and argue about measurements. Please let us enjoy this forum by limiting your postings exclusively to other forums. We would all be grateful if you did.

If you read the earlier postings in this thread I was already involved. You meridian owners are really agitated. Its funny how people are offended when questions are asked about a product, or do you blindly support what your dealer tells you? You just assume what I do or don't own and what I can and can't afford.

If you read the earlier postings in this thread I was already involved. You meridian owners are really agitated. Its funny how people are offended when questions are asked about a product, or do you blindly support what your dealer tells you? You just assume what I do or don't own and what I can and can't afford.

Although recently you have luved the Anthem D2, you have never come out and said that you have demod or owned it or used it, or any other surround processor that I can recall. It would be nice if you would give us at time your experience using audio and video products as opposed to only your alleged "technical" expertise which has been shown time and time again to be totally lacking compared to folks like John Kotches, Glimmie, Amirm, Dennis Erskine, and many others.

If you read the earlier postings in this thread I was already involved.
You were already involved arguing about measurements...again.

Who says this? If it has a negative impact it can be measured.

Not everything can be objectively measured although many things can. For example, your negative impact on this forum cannot be measured yet is present in the minds of many of us here who actually own and talk about gear we own. Something you never do.

Although recently you have luved the Anthem D2, you have never come out and said that you have demod or owned it or used it, or any other surround processor that I can recall. It would be nice if you would give us at time your experience using audio and video products as opposed to only your alleged "technical" expertise which has been shown time and time again to be totally lacking compared to folks like John Kotches, Glimmie, Amirm, Dennis Erskine, and many others.

Lacking? I am one of the few who actually post numbers and information to back up what I say, I see nothing but assumptions based on subjective opinions coming from other people. What I have owned/listened to is irrelevant becuase it does not change anything I have said.

You were already involved arguing about measurements...again.

I was giving advise before I was attacked with name calling, he is running martin logan speakers so obviously his choice of amps would be limited and theta would not be able to cut it. Or do you not think that the ohm rating of a speaker matters?

Who says this?
The people who know more than most of us :). Here is a good article with Spice simulations and all: http://www.normankoren.com/Audio/FeedbackFidelity2.html.

If you don't know Norman, he is one of those crusty engineers who was awake in school while the rest of us were dozing off in our engineering fundamentals class :).

Just search for negative feedback and you will see more articles than you can count.

But you don't need to go that far. Here is some layman logic. Feedback loop is just that: taking the output and connecting it to the input. As soon as you have such a connection, then there is a possibility for instability and oscillations. The longer/larger the loop, the harder it is to avoid this.

On the harmonics, that is also easy to see. Imagine an amp putting out first, second and third harmonics. In other words, if you input 1Khz, you see shadow responses also at 2 KHz and 3 KHz. Now sample the output error (the harmonics) and feed it back to input (what negative feedback is). By doing that you are now feeding 2 KHz and 3 KHz as input. The amp goes and creates shadows of those at 4 Khz, 6 KHz, 9 Khz. So now you have a number of higher frequency components you didn't have without feedback.

Mind you, negative feedback would have reduced the 1KHz and 2 KHz components (hence the better THD response). But it doesn't take much for something to sound ever so slightly bright or inaccurate in higher frequencies.

If it has a negative impact it can be measured.
Sure. The spectrum analysis will show the increased harmonics. And we can measure the harder clipping. And show them at theory level (see Norman's article).

Why do you post on the Ultra Hi-End HT Gear ($20,000) Forum? You don't own a high-end home theater; you don't aspire to own a high-end home theater; you can't afford a high-end home theater; you have never actually heard any high-end equipment; you constantly bash high-end equipment and tell people not to buy it; and all you want to do is hijack the threads and argue about measurements. Please let us enjoy this forum by limiting your postings exclusively to other forums. We would all be grateful if you did.

That is exceedingly well put.

Mr. Winsor is a troll who is best just ignored. You are all wasting your time trying to reason with him; time and time and time again he interjects his particular brand of nonsense, misinformation, and total lack of experience and understanding into 20K+ threads for the sole purpose of baiting other members, and ultimately distracting/derailing threads until everyone else gets tired of it and leaves them.

Sure. The spectrum analysis will show the increased harmonics. And we can measure the harder clipping. And show them at theory level (see Norman's article).

Tube amps aside, so you agree that if there is a negative effect and it can be measured then we have no problem.

Mr. Winsor is a troll who is best just ignored. You are all wasting your time trying to reason with him; time and time and time again he interjects his particular brand of nonsense, misinformation, and total lack of experience and understanding into 20K+ threads for the sole purpose of baiting other members, and ultimately distracting/derailing threads until everyone else gets tired of it and leaves them.

- How am I a troll
- What nonsense
- what misinformation

Tube amps aside, so you agree that if there is a negative effect and it can be measured then we have no problem.
I am not going to express my own opinion. Don't feel like defending any side of this. :) Just explaining the science behind the position taken.

The negative effect is as stated. Do you care if clipping is hard or soft? One sounds good until the edge and then sounds horrible. The other sounds a bit worse but there is not as much of a cliff.

Do you care if there are frequencies 6X higher than what you put in?

Do you care if the machine can oscillate?

All of the above can be measured. If you don't know how, ask, I will explain.

What cannot be measured is the effect on everyone's ear. If we could measure that, then there would be one amplifier design and all others would be abandoned. So as it is, you are the mercy of the amp designer and your own research (both into science and listening) to know which technology solution meets your needs.

I said I would not express my own opinion. But here is a bit I have said :). I have multiple versions of the Stax headphones (electrostatics). They come with their own amp that drive the high voltage transducers. I first bought the transistor models. I was blown away by the quality. But then bought the tube unit (which uses local feedback as described). I could not believe how much more musical it is. I mean tonally it is a completely different animal. Something tells me it would measure really bad. But I don't care, it sounds amazing. The fluid, analog quality to it just can't be approached by the transistor version.

So if you just go by numbers and what you can measure, you would have never experienced the enjoyment the tube unit brings. Ultimately, there are things in audio we just can't measure. The best example is compressed music. It will have full frequency response of a non-compressed music, but it can sound substantially different and this varies every few milliseconds!


- How am I a troll
- What nonsense
- what misinformation
I am not sure of the history of folks in this forum so no opinion one way or the other :). But I do watch how people interact when presented with data. Whether they bring data of their own, or keep saying "I don't believe it, show me more." The latter adds no value to the forum. It is not like there is a shortage of people who don't believe in high-end anything :). So decide which bucket you want to be in. The bucket that contributes to the discussion (and that can certainly include disagreement) or not. Read every post you make and see if it is useful in some manner. If it is pure opinion, expressing it once shoud have been enough :).

The negative effect is as stated. Do you care if clipping is hard or soft? One sounds good until the edge and then sounds horrible. The other sounds a bit worse but there is not as much of a cliff.

I do not approach clipping in my amps since I do not run tubes and I have lots of power to spare.

Do you care if the machine can oscillate?

Funny you should mention that since people have blown out their tweeters by having an amp that will oscillate.

I am not sure of the history of folks in this forum so no opinion one way or the other . But I do watch how people interact when presented with data. Whether they bring data of their own, or keep saying "I don't believe it, show me more." The latter adds no value to the forum. It is not like there is a shortage of people who don't believe in high-end anything . So decide which bucket you want to be in. The bucket that contributes to the discussion (and that can certainly include disagreement) or not. Read every post you make and see if it is useful in some manner. If it is pure opinion, expressing it once shoud have been enough .

I bring in technical specs and proven/measureable data, the other side brings subjective opinions.

KSA 200S. It is a fantastic amp for my CBII before, CBIII and Integra 9.8 today while I am waiting the HDMI upgrade. I can't tell you how much I love it. I am just try to consolidate 3 amps, 1 Krell monoblock for center, KSA 200S for stereo listening and movie L&R and KSA 500 4 channels for rest of the 4 channels to 1 amp such as DN1, DN2 or TAS now.

Have you experimented with bi-amping your Logans? I recently added an inexpensive 2 channel amp (Onkyo) to my system to drive my rears (Paradigm in-walls) to free up two channels on my Krell 5 channel Showcase amp. Now I'm bi-amping my ML Vistas and the difference is quite dramatic. Is the 7 channel version of the TAS on your list (I assume there is one as the Showcase has this option)? Of course, the Vistas don't have a powered woofer so the extra power might not be needed if your Logans are the powered variety.

I do not approach clipping in my amps since I do not run tubes and I have lots of power to spare.
Which amp do you have and what speakers are you driving?

I am curious, how does an amp's input impedance affect things? Isn't this an issue when matching SS gear with Tube gear? Theta's input impedance seems on the low side at 50 Kohms whereas most others are at 100 or above.

To the original poster – I could own Krell again or Theta or even something else down the road…just depends on my ears. I can comfortably say that I am more than pleased with my set-up right now, and more often than not amazed at the illusion when I listen. I have no desire to change anything just for the heck of it. Nevertheless, I cannot stress enough that you should demo these pieces for yourself rather than listening to anyone here or elsewhere.

Is the 7 channel version of the TAS on your list (I assume there is one as the Showcase has this option)?

The TAS is fixed @ 5 channels. Only the S-1500 has (as did the Showcase) the ability to go from 5 to 6 or 7 channels with plug-in modular boards.

Ah.. good to know. thanks

I am curious, how does an amp's input impedance affect things? Isn't this an issue when matching SS gear with Tube gear? Theta's input impedance seems on the low side at 50 Kohms whereas most others are at 100 or above.
As a general rule, you want the input impedance to be the highest it can be, and the output the lowest. The former helps with loading of the pre-amp. The lower the impedance, the harder the pre-amp has to work to drive it. And the harder it works, the more potential for distortion (same idea more or less as your power amp being underpowered).

Having said this, I am not sure that one can automatically equate lower impedance as a lower quality amp. But it is a good thing to look at.

Just sold my Krell 2 channel amps and looking for a 5.1 amp now.

What do you guys think about a used Dreadnaught 1, $1.5K more for a Dreadnaught 2, Krell TAS or do you guys have any suggestion about $3K 5.1 amp?
Hi,which M L do you have,i run prodigy,logos and requests.i have listen to theta it made music,i own KAS 5 channel as well,if your using older large M L i would go with krell will be much harder to clip,has 2 x 2kw transformers,bat is an option also,newer krells sound better,note i run krell with audio research ref 600mkIII for left and right channels and the krell does a good job and in home theatre hard to notice it is outclassed,audition amps at home will help,
regards victor