I've narrowed it down...

Rfogel8, you have me laughing. Not for the faint hearted.

Botit,

I have a Cary sli 80 sig i would like to sell if your interested.

Hey, you haven't lived til you experience a catastrophic tube failure.

In my experience, you simultaneously get loud crackling and spitting noises from your speakers as a light show appears from the offending amp. This is much better if the lights are dimmed.

Smoke will often rise from the amp's chassis, but with a little luck, the fuse will blow before any serious damage is done.

As you bolt from your easy chair to turn things off, heart racing of course, you'll no doubt get that familiar smell of burnt electrical parts. Gee, it doesn't get any better than that!

Lest anyone think I shy away from tubes on the mere chance one might fail, there are 68 tubes employed between my two systems and I never worry about it.

I have never heard a tube fail catostrophically, but I have heard a tube that was starting to go out. In that case the music started to break up a bit when we started pushing the speakers.

How do you know when it is time to replace a tube does it simply fail? On one minute, off the next?

Botit,

Of the amps you have listed in your original post, I would go for the Rogue Tempest III.

Every bit of audio equipment ever made has warmup times at least that long. Not that you can't enjoy it long before that. Many years ago when I still ran transistors, I had to leave them on 24/7 so they would sound their best. It took them a week to warm up.

They are all like that, but 15 minutes is more than enough to warm them up unless you really want to get paranoid about it. Tube life is very dependent on the tube used and the ciruit it is in - some output tubes in some amps will go 2,000 hours, the ones in my Music Reference RM10 MKII are said to go 10,000 - you need to ask the manufacturer of your particular amp, and the input and driver tubes usually last longer than the output tubes.

I was doing more research prior to purchase today and saw that one manufacturer recommended an hour heatup of the tubes prior to listening... Are they all like that? Is there a down side to leaving the amp on (other than shorter tube life) which brings me to the next question. What is the expected tube life?

When I was listening to my Technics receiver driving my JLB L19s in college, who knew that one day Class A, Triode, OTL, No NFB would one day meaningful to me:)

Atmasphere,
I 'suspected' true triodes are more linear thus they don`t need to rely on feedback.Thanks for taking the time to explain the instrinsic differences between triode and pentodes, very educational.
Regards,

Unsound, The 3rd harmonic is one of the lower orders and is the only one considered musical with relation to the fundamental by the human ear. So Nelson's comment is spot-on.

When Crowhurst was writing, it was not generally understood at the time that the odd orders (above the 3rd) were the distortions that the ear finds unpleasant, although you will see Crowhurst refer to 'listener fatigue' with respect to the use of feedback. IOW he knew something was up, but some of the aspects of the human ear simply were not understood at the time.

Charles1dad, the DHTs are far more linear than tetrodes or pentodes. In fact all triode tubes (whether directly-heated or not) are quite linear, enough so that is is fairly easy to build an amplifier with them that does not need feedback. Triodes in general will generate distortion that favors the lower orders while the tetrodes and pentodes generate more distortion and also more of the higher orders and so tend to sound harsher, thus the need for feedback with them.

If you speak to almost any SET designer, they will likely tell you that the lower orders that their amps tend to make are not objectionable to the human ear, which is true. They do color the sound though- the ear hears distortion as tonality- so the lower orders contribute to the 'rich' or 'lush' sound of SETs.

Charles1dad, I think you'll find plenty more of this in the archives.

It has gotten some what off topic yet very interesting and informative,good thread IMO.
Atmasphere do DHT tubes behave differently from IDHT(Pentode) type tubes and would their response to feedback be the same? is one type more linear than the other? could that explain why some SET amps with DHT tubes can perform well without the need for feedback. Suprisingly the Yamamoto DAC I use is SS yet the builder uses zero feedback(he claims even 1 db of feedback is noticeable in the circuit).
Regards,

Atmasphere, the requests I made were for articles you have referenced before that are other than the Crowhurst. Since my previous post was not specific please refrain from making misleading statements regarding me. You generously provided a lengthy Crowhurst link in the past. In that article, Crowhurst suggested that negative feedback could be usefull, but it was important not to abuse it.
Once again, I will remind you that according to Nelson Pass some people prefer the odd 3rd order.
Once again, we seem to be straying off topic.

Unsound, you used the phrase

numerous requests

Your request for links which I provided does not constitute the above and my response also satisfied your lone request.

So your statement above is clearly misleading.

With regards to Norman Crowhurst, he does imply that negative feedback is beneficial. I pointed to him because he supports my claim about odd orders being distorted in a small degree by the presence of negative feedback. IOW he does not make a value judgment- that is made elsewhere, for example by Nelson Pass.

However in Crowhurst's text if one is familiar with Chaos Theory http://en.wikipedia.org/wiki/Chaos_theory we see that Crowhurst shows the formula for feedback; compared with that of a classic chaotic system that the two are nearly identical. He also mapped the Strange Attractor that is characteristic of the resulting Chaotic system that an amplifier is when using feedback. These things are not coincidental; the presence of bifurcation (distortion) is predicted by Chaos Theory and Crowhurst, despite Crowhurst's writings preceding the formation of the branch of science we call Chaos Theory.

Now the fact that Chaos Theory predicts negative feedback to be a destabilizing factor in amplifier design is something that should not be ignored (BTW, many designers will mistakenly claim that negative feedback is a stabilizing factor). However no value judgment is made, simply the expression of what is.

It is other studies including the rather simple and repeatable test (to which I have already referred) that make the value judgment. That judgment is not entirely mine, BTW, but a fairly large consensus in the audio community which agrees that odd orders are unpleasant to the human ear (and is the reason that over 50 years after the introduction of transistors, tubes have failed to become a footnote in audio history). All I have done is outline what is.

Yes the Atma-Sphere S-30 was used in the voicing of Audiokinesis designs, but IIRC so was NuForce. Duke happens to be a dealer for both brands so he certainly had access to each.

My reasons for recommending these speakers is really about the flexibility and the fact that you can audition many types of amps with little worry as to compatibility. I have run 2 watt 45 and 12 watt EM7 SET amps, 35 watt EL-84 push pull, 70 watt KT-88/EL34 push pull, and 300 watt solid state amps with my speakers and the sound has always been pleasing, if not somewhat different.

I'm sure there are other flexible speaker designs out there and if I were the Op these would be the types of speakers I would focus on. I for one am in the camp that the system should be built around the speakers.

I 2nd Clio9s recommedation of Audiokinesis for a speaker line to consider. A great sounding speaker with the lower powered Atma-sphere S30s (30 watts, Class A, Triode, OTLs) - a killer combination at a relatively low price (for this hobby). I think the speaker was actually developed with the amp which goes a long way to ensuring amplifier/speaker compatability. If I did not own the Merlin VSMs, it is a speaker line that I really would be interested in; it caught my attention at RMAF.

When all is said and done I believe the need/advantage for feedback comes down to amp design and certainly the speaker involved. Some speakers simply don`t need the additional damping feedback provides, other speaker types would benefit.

The proof is in listening, my amp has no loose bass or undisciplined problems,there`s good control,articulation and nuance, so feedback is`nt always mandatory. In the end what matters is proper amplifier-speaker compatability.
Regards,

Israel, said that SET's sound there best without any feedback. What say you Atmasphere. I think Very little local feedback is not a problem and helps most speakers drivers not flop all over the place.

Jwm,
Israel Blume(Coincident) confirmed the Frankenstein amp does`nt use any negative feedback, global or local. He said it is a zero feedback circuit.
Regards,

Jwm,
I believe you are correct for the most part,but it really depends on the speaker you intend to drive. I do 'think' that some lower power SET amplifiers(I think my 300b amp is one example)operate without'any' negative feedback at all. This may be possible due to their inherent linear character. If this is the case then of course appropriate speaker selection is a must. I`ll check with the builder of my amp to be sure.

Great posts, I see what Atmosphere is trying to convey. I personally like tubes better than solid state, but I think some local feedback is needed with most speakers to control the back wave of the woofer. When I say some feedback I mean very little like 4-10 dbs. I am not sure if any amp made is truly zero feedback. Maybe globally, but locally I think all amps need a little feedback to work.

If you are willing to commit to a new pair of speakers, are you willing to spend $2700 for a set that are flexible enough to be used with tube (SET, PP, OTL) or solid state amps, and still sound outstanding? That can handle a wide range of power output (5 - 500 watts)? That also provide for flexible room placement? If so:

http://audiokinesis.com/product_ak_rhythm-prism.html

If you're willing to go a bit higher:

http://audiokinesis.com/product_ak_prisma.html

Yes Botit, I think that is very true, changing speakers will change the sound of your system in a much more obvious way than changing amps, and down the road you get the amp that will take your speakers to a higher level. That would be my approach if you are looking to make a real change in the sound of your system and if you have to do one thing first and the second down the road.

Mikirob,
Oh I very much trust my ears(there`s no better way) That`s how I got to SET amplifiers. My question for Atmasphere was academic in nature,tube amp designer vs competent SS designer.
Regards,

This has been very enlightening. Since I am only replacing one of the 2 options (amp or speakers) I think I'm in a do-loop... Upgrading the speakers first would give me an improvement in sound now and more improvement when I purchase the amp, and likewise if I purchase the amp now. I understand that my process may not be ideal. I have learned a great deal on this thread and appreciative of your willingness to share your knowledge and experience.

Thank You.

Regards,

Atmasphere, I am not making misleading statements. I myself have repeatedly made such requests. In the past you have referenced Crowhurst, upon reading those links, one would discover that Crowhurst actually suggested that some feedback could be beneficial. But...we're getting of topic now.

Unsound, I have also outlined how anyone with modest test equipment can prove what I have said for themselves. There are even 'goners that have set up the test themselves and come up with the same conclusion. Check the archives; your statement to the contrary, I've not seen 'numerous requests'; please refrain from misleading statements.

How do you debate with equally renowned SS builders i.e. Pass,Gryphon,Vitus,Boulder.Soulution etc. who would I`m sure insist their products produce music as'real' as any tube component and possibly better?

Nelson and I are often on the same page. I often refer people to the distortion article on his website:
https://passlabs.com/articles/audio-distortion-and-feedback

In it we see that adding negative feedback does enhance odd-ordered harmonics, which *maybe* you could sort out by having even more feedback, although you would need to add more gain to do that, likely requiring even more feedback...

The fact that feedback does have this effect of increasing odd orders was also documented by Norman Crowhurst 50-some years ago. You can find his articles on http://www.tubebooks.org (vol. 3 of Basic Audio).

I totally concede I have a bias towards tubes, although if you were to check the archives I have often mentioned that I think we can get to the same performance with transistors, but they often fall short on account of its a lot easier to build a linear circuit with no feedback using tubes than it is with transistors. With regards to the other manufacturers, the debate has not actually occurred as most of the ones you mention are not active on this or other forums that I frequent. However I would likely point to past work at the links I dropped above for starters.

As far as the human hearing rules, the fact that we use the odd orders to determine how loud a sound is is easily proven with modest test equipment. I'm happy to provide the test procedure if you like; Unsound that goes for you too.

Who does that? :)

Charles1Dad, all one has to do is trust one's own ears in ones own listening room.

No, I don't want to go on and on so I won't be checking the archives as it does't really matter that much. I trust the original poster can read between the lines and shall make whatever decision he makes and goes on a similar path as most all audiophiles and music lovers. Best of luck Botit...

Mikirob, I humbly suggest you check the archives. I've been down this road many times before with other fellow Audigoners. Unlike Atmasphere I don't have a commercial interest in this field with a website to hyplerlink to whenever this subject comes up. If you do such a search, you'll see that despite numerous requests, Atmasphere has yet to provide these research papers he repeatedly refers to. I wasn't suggesting that it was the only way, just the better way. I only brought it up again as it seemed especially relevant to the OP.

Atamsphere,
What you explain in technical terms make plenty of sense. Some would say you`re obviously bias toward tubes(the products you build and sell). How do you debate with equally renowned SS builders i.e. Pass,Gryphon,Vitus,Boulder.Soulution etc. who would I`m sure insist their products produce music as'real' as any tube component and possibly better? My ears lead me to tubes but I could`nt make an arguement with a technical viewpoint as you are able to do.

Obviously, I agree with Atmasphere here since I am a tube guy; but the discussion is not SS vs Tubes, but what component do you buy first? Speakers or Amp? The real question is SS or tubes to contradict myself. After that decision is made then it's what speaker type will be best.

That's the point, it goes either way depending on fiat and personal circumstances for most people. If I were a newby like everyone once was, I'd likely would first have to ask myself this question: SS or tubes? Say I chose SS. Ok, what speakers? For argument sake say, Maggie's 1.7. OK, I do research and work with dealer to try stuff that is good, synergistic match. I purchase super duper power house amp that Jonathan Valin has blessed as it sounds great in my room to my ears also.

Another scenario: I'm a newby, hear a friends system, it's a Rotel integrated, with Sound Dynamic 300 ti speaker and associated friend shows you Absolute Sound Mag and Harry Pearson article, great speaker to price ratio recessed midrange like electrostatic speaker A. Newby asks, "what's a electrostatic?" Friend explains, adding lots of mumbo jumbo newby doesn't understand, but knows he wants a system like his friend for music. Newby buys most of audio mags, reads all the articles and reviews and talks to his 1 friend that has a decent stereo. Newby travels to the 2 high end dealers he found out about, 100 miles apart and a 2 hr. drive either way. Newby makes the drive to each dealer, one is worse than the other and he finds out his $5,000.00 budget is crap and he is a worthless human being, they, the dealers, have little time for him and brush him off. Newby leaves humiliated and humbled. After some research he learns about John Rutan at Audio Connection in Verona NJ, 3 hrs away; he makes the drive. John is totally unlike the previous dealers, spends tons of time talking and listening with said newby. No sale today, but newby comes back another time and learns more, listens more, knows more. John has been kind and patient. Newby walks out with Vandersteen 2ces, Rotel like his friend, cd player. Newby now knows better amps will make those Vandy's sing better, he just doesn't have the $$$$ dollars yet. But he has learned the Vandy's can go with him through a number of amp upgrades before he'll want to move up the Vandy's food chain and/or other components in his system.

These and other scenarios are more real world process rather than the blanket Speakers First approach, although it works well its not the only way nor necessarily the fastest way to audio nirvana. It's a process, many intended and unintended consequences occur along the way.

Hi all ! I think I did it backwards too . I decided on a 4wpc otl tube amp then ordered the speakers . Perfect match ! In reality it can work out fine both ways .

what is it that makes one speaker sound better on ss and another on tubes? Is this an experience item or are there specs I can look at?

Maybe you should look here first:

http://www.atma-sphere.com/Resources/Paradigms_in_Amplifier_Design.php

In a nutshell tubes drive speakers differently than transistors tend to, although you can make them do it if you add enough feedback. The problem is that when you do this, you will also rob them of the music. IOW, its not so much a transistor/tubes debate as it is whether or not making an amplifier into a Voltage Source is a good thing or not.

To this end I don't agree with Unsound, as the research that has been done in the last 45 years points to the fact that the human ear is very sensitive to the use of feedback in an amplifier, and also that it hears harmonic distortion as tonality. Another way to putting this is that you will have a very difficult time to get the equipment to sound like music and run feedback at the same time.

The B&Ws require that the amplifier be a constant voltage source which is why they don't work so well with tubes.

So if you want tubes, you *have* to find a speaker that works with them. If you go with the speaker first, you may be forced into using a transistor amp. Since most transistor amps use a fair amount of feedback, its nearly impossible to get such a combination to sound like real music- at best it will sound like a good hifi. Its that last nuanced difference that brings home the bacon!

Now you could try using transistor amps that have no feedback; there are a few around like the Pass Labs and Ayre. The problem is that transistors have non-linear capacitive aspects in the junctions of the device itself. This contributes to odd-ordered harmonics- the very thing that the ear uses to sort out sound pressure (volume of a sound).

Another way to put this is that the more the equipment obeys human perceptual/hearing rules, the more it will sound like real music. In a nutshell its easier to do that with tubes than with transistors- I am not saying that its impossible with transistors, just that its several orders of magnitude more difficult.

Hi Pubul57,
The reality is we`re both obvious exmaples that either way is fine,it`s really no big deal. If Botit gets a tube amp first then an appropriate speaker his chances for sucess are as good as mine were. He will do well.

If you want to own SETs, you do proabably have to make that decision first and the find appropriate speakers and I suppose in the real world this might very well happen. However, if I were advising someone, I would still tell them to find the speaker the love first and then find an amp to drive it since I think the speaker has a much greater impact on the sonic signature of a systems than any other component, and then tweaked a bit through the selection of electronics, but the recording, speaker and room are at the heart of a system's core performance and sonic attributes IMHO. Of course you could find an amp first, but that would limit speakers you could audition and fall in love with - though some speakers may need high powered SS or tubes, and yes even sometimes SETs to sound their best.

I don`t want this to disintergrate into another tube vs SS (again, sigh)I freely admit amp'or' speaker first appraoch can work out well.

When it comes specifically to SET amplifiers you 'most' often will begin with the amp you like and just find a good efficient-easy load speaker to match.Fortunately on the current market there are many to choose from.

Unsound, so why don't you give some concrete scientific back-up to that reasoning. In the real-world what I stated is the more likely scenario as to Charles1Dad attests; this is also my real-world scenario. My father and uncles all had great tube systems in their day. Me, I started with SS, was very unhappy, something was always missing, it just wasn't right for me. The more tube systems I heard, the more I understood what I was missing. My parents and several relatives are musicians, I am also, among other things, know what "real" music sounds like. In the professional music world I and most of my colleagues didn't ' select speakers first, we bought the guitars, musical instruments we liked, then the Marshals, Vox, etc.

How and why should a person say, oh, I must, it's mandatory to go speaker first? Say you inherit an amp. You don't take it because you don't have your ideal speakers? When I got my first SET amp I had big inefficient speakers that I had to change. No big deal, no harder to do that than doing it the other way around.

How and why do you believe this theory of yours?

Mikirob,
Your example is my historical reality! My first high end systems for competely SS gear.Over time I was introduced to tube amps and preferred them by a consideable degree.
Once exposued to the genre of SET amps if was all over,I found them much more natural and closer to what I hear with live music.

I bought a 300b amp built my system around it and it exceeded my high expectations. I enjoy the best music reproduction I`ve ever had(by far). Absolutely either a amplifier or speaker can be the building block for an audio system. I know I`m not the only one who has sucessfully done it this way.
Best Regards,

Mikrrob, I get it and didn't misread your post, I just disagree. I don't think one should buy speakers for amps. I think one should decide on speakers before choosing amplification.

I think tubes do wear out faster when asked to drive more difficult loads

That very well could be. I ended up selling the B+Ws shortly after I got the tube amp, I had gotten the upgrade bug by that point anyway.

I agree no harm would come to the amp, but I think tubes do wear out faster when asked to drive more difficult loads, not sure by how much, but that is my understanding (though I could be wrong, but I'm sure the more technically adept would be able to say more definitively).

I don't think that 20 watts is adequate to drive the B+Ws, regardless of the amplifier's implementation. The ones that you mentioned in your original post put out around 70 to 90 watts, and that should be fine. I don't think that you'd shorten the life of a tube amp (or the tubes themselves) by using one with the B+Ws, that was not the experience that I had. It just didn't sound good; in my case, everything just sounded flat. You mentioned that you're moving, so maybe the thing to do is wait for a bit, get settled first, figure out your 2-ch listening space and then look into buying an amp and speakers at the same time.

-Mike

Unsound, you don't get it, or misread my post, where I basically agreed with your premise under ideal conditions. So, let me give you another example where it might not work out that way.

Let's say I'm a newby like we all were at one time. I put good money into a SS amp like Threshold, SS Pre, big name brand inefficient speakers and ancillaries. Then, over time after listening to many pals systems, going to some dealers in my area and the big Audiophile shows I realized I liked the sound of low-powered SET tubes best of all and wanted to make the transition from SS to tubes.

What to do? I have a bunch of funds tied up in my SS rig and modest funds available to me, yet since I've done some preliminary thinking, at least I know I want tubes, I'm going to liquidate my SS stuff on Audiogon and elsewhere. While I'm in the process of doing that selling, a friend offers me a really good name brand SET tube amp, that I have heard and really like with various speakers, the price is good and I can afford it. I take the plunge and purchase it. Now I have the amp and know I must find a synergistic speaker match for my listening room and my listening preferences. Of course I have a pretty good idea where to Start.

So, in short the chicken or egg can go in either direction. It might depend on your individual circumstances. So, what is the big deal about auditioning speakers with an amp I know I already like. Not any harder than buying the speaker first and finding an amplifier IMHO.

2K for integrated amp.

No budget yet for speakers.

My current (HT) setup...
Reciever; Pioneer VSX-94txh
Front; B&W 602 S3
Rear; B&W 601 S3
Center; B&W LCR 600 S3
Sub; Outlaw LFM-1

The 602 S3's will act as the speakers for the time being until I make the dedicated 2ch speaker purchase...

what is a reasonable amount of power to consider? is 20w/ch enough? are tube w/ch different than ss w/ch?

I think that a tube upgrade would certainly increase the quality of the sound I currently have, the question now is would my existing speakers cause damage to an integrated tube amp?

When you say hard on a tube amp what does that mean? Will i need to replace 5000 hour tubes in 20 hours or after 4500 hours?

"speakers will have a greater effect on sound than amplifiers..." And not by small margin IMHO. OP, what is your budget for an amp and speaker transition? Even if done in stages?