Kijanki,
I believe your right in that the vast majority of amplifiers use some degree of NFB.I think DHT SET amps are a small niche that can be the exception.
Regards, |
Dracule1,
I agree this is semantics, we all seem to be describing the same natural character of acoustic bass.The difference is our individual ways of achieving this sound in our systems.You chose PP tubes,Kijanki with class D and me with SET amps. Different ears ,different solutions.
Regards, |
Dracule1,
I don`t agree with the myth description.It just depends on the amplifier`s chosen output devices and the particular speaker being driven.What good is it to reduce 2nd order harmonics to extreme levels and then replace it with odd high order harmonic distortion(worse),that`s a bad trade off.A tiny amount of this NFB odd order distortion is not natural to human hearing and is processed as irritating and artificial.
Some speakers do require amplifiers with NFB. I`d prefer speakers designed that don`t 'need' these types of amplifiers in the first place.Amps without NFB sound more natural and realistic in my own experience, YMMV.
Regards, |
I don`t agree that 'every' amplifier has NFB. There are some DHT SET amplifiers that lack NFB in their circuit.Some of these types of tubes are linear enough so that it is`nt necessary.My amp is one example(unless Israel Blume told me a fib,and I doubt that).
Regards, |
I have two push-pull class AB amplifiers. One is 40 watt/ch with EL34 tubes and the other is 100 watt/60 watt(UL/Triode).The bigger amp is one of the best PP amps I`ve heard it uses 6550/KT 88/KT90 etc. This was my main amp,top choice for driving my Coincident speakers. Three years ago I purchased my 300b SET 8 watt amplifier.From day one fresh out of the shippng carton this SET put the others into storage. It was simply better across the board.
The 100 watt amp has more bass weight and impact(the gap is`nt large however).In terms of tone,harmonics,noise floor,presence,3 dimensionally,nuance and dynamic ebb and flow the SET is superior.When playing high energy big band jazz ,the ability to clearly seperate and hear the individual instruments is extraordinary.The scale,energy and dynamics completely fill my room, it really as if the walls vanish(I`m right there at the venue,spooky real). In the sense of realism,believability and natural sound it`s the best I`ve heard so far.Some SET amps are better than others.The better quality DHT SETs are the most live-like,realistic and trueful amplifiers I`ve ever experienced. This was a profound moment for me as it put me into a different sonic realm,there`s no going back.I`ve own SS (Symphonic Line amplifier) it was`nt close to this.My 100 watt PP was better than it in terms of live flesh and blood presence.The 300B SET is a new standard however.
Just an example of how people have different experiences and impressions. The good news is there`s an amplifier topology out there for everone. SET,PP,OTL,SS,class D, take your pick.What I have discovered with SET I know others have experienced with other types of amplifiers also.
Regards, |
Mapman,
In my experience the answer to your question is no. The one quality I`ve come to admire over time with my SET is honesty. What ever is the inherent sound character of the CD that`s what I`ll hear,flaws and all. Some SET amps could perhaps'pretty up' the sound but my does`nt do that. I have some recordings that are thin,brighter and in some cases edgy and that`s how they will sound.But those that are recorded well,oh my goodness.
My SET has less editorializing than all of my previous amplifiers. I reconized this aspect early on, It just seems to preserve the signal with minimal influence.The effect is heard as pure and unfiltered.
Regards, |
Mapman,
I`d agree with your thoughts about appropriate amp for your Triangle monitors.My path was simplified by matching amp and speaker by the same builder. His objective was cbviously very good compatibility.
Regards, |
Atmasphere,
Your explanation of the natural noise floor compared to the 'harmonic noise floor' sounds absolutely right,here`s why. I know my former Symphonic Line and my PP tube amplifiers will measure lower distortion than the 300b SET amp. Yet when I listen to familiar music with these amps the SET in reality had the lowest noise floor for actual listening. It teveals more nuance,inner detail,ambience clues, all the subtle sounds that were either buried or not heard at all with the other amplifiers.This contrast is very apparent. Thanks for this explanation. I could hear all of this easily but did`nt understand why.This is likely a major factor why evrything sounds substantially more real and convincing with the DHT SET in place.It all makes more sense now.
Regards, |
Dracule1,
"the ears have the final say"
This is right and the reason we`re all stating our preferences.I won`t argue with what you hear and say you`re wrong,we just differ based on personal experiences.
As I said in an earlier post,that`s why there`re numerous types of amplifiers in the high end market place.
I found DHT SET no NFB the better choice based on my ears. Your ears led you to PP pentode with NFB,The good news is we`re both very happy,choice is wonderful.
The bass debate may just be semantics regarding the term 'tight'.Two nights ago I had the pleasure to see(and hear) the Bill Charlap trio. Peter Washington was playing the acoustic bass. the club is intimate and unamplified, I was within 10 feet of the stage. The sound of peter`s bass was just beautiful,very full,round, dense and there is much a sense of bloom.I did`nt hear tight or taut,(it was`nt loose and sloppy either, but it was a bit'fat')even when he played very up tempo. The notes seem to linger with much substain and decay, just beautiful live and up close.I do believe there are audiophile qualities/expectations that appear to vary from the reality of live acoustic instruments. If some audiophiles were blind folded and heard peter`s bass playing(but told they`re hearing a system and judge it) they might say it lacked tightness and was too warm and round.People like what they like,but many audio components tend to thin and make the sound leaner(tighter?) than real life presentations i.e. fuller tone and body with weight and presence.
Regards, |
Dracule1,
KT88s are beam tetrodes as you state. They are grouped and interchanable with the power pentodes(6500,EL 34,KT 90.120 etc.). Many amplifiers(such as mine) allow use of most of these, especislly KT 88 and the 6550 tubes.DHTs are a completely seperate catagory altogether.
Push pull amps can sound excellent(my Bella Extreme 100 monoblocks built by Bill Baker and my friend`s VAC Phi 300.1 monos). There`s just a different character to the sound.
Regards, |
Dracule1,
A 300b SET has 'very little' heat output.There`s only 1 output tube(8 watts) per monoblock.My PP amps run much warmer with 4 6550 per side. You may never prefer a SET no NFB compared to PP with some NFB. I`m just giving my own preference(after living with both amplifier types with extensive direct comparisons) and by no means making any sort of proclamation that applies universally.I wish you continued enjoyable listening with your system. |
Learsfool,
Thanks for your comments and viewpoint.I made it a point to be clear about the enrivoment in the jazz I attended.Kenny Washington`s stand up bass was 'natural' and unboosted. Definitely not'tight' in the audiophile sense.This is why IMO tube amplifier bass sound more real than most solid state when reproducing acoustic bass, there`s no artificial'slam' added.I do appreciate though that many do like that 'slam' factor and I`m likely in the minority..
Regards, |
Hi Dracule1,
I `ve never read or been told that NFB exists within a tube`s internal/intrinsic construction.I don`t believe that"every amplifier" has NFB. I`m not an engineer nor a designer of audio components but I think some of them would disagree with your friends statement.When people talk of NFB it`s in terms of deliberate insertion into a circuit either globally or local loops.
But really it`s just what sound we all prefer.You like some NFB in your amps circuit and that`s fine.What ever no or zero NFB is, that`s what sounds best to me when properly implemented.This has been an interesting thread and I appreciate the various points of view.
Rgards, |
Frogman,
Your comment concerning "accuracy" rings true. Last night a friend and I attended one of our favorite jazz clubs.The quartet consisted of B3 Hammond organ,alto saxaphone,guitar and drums.The sound in this venue just sweeps you away with beauty and presence. Driving home we both kept referring to how rich, warm and full these instruments sound and project when heard live and up close.
What we both heard was the real deal,beautiful rich tone,complete fullness, weight and tonal saturation...accurate(because it`s real).
Components that strip away the'natural'charcter and result in leaner,thin tone(less color saturation) and body are`nt accurate,they`re inaccurate.I don`t understand why this approach has now become accepted by some as "accuracy". It moves further away from what you hear in the presence of live musicians doing their thing.
Regards, |
Onemug,
Yes, the objective (at least for me)is to capture as much of the true sound of live instruments that`s reasonably possible.That`s the best template I know of. I realize others disagree but I`ve found no better way to obtain good sound at home.
Regards, |
Csontos,
I`m speaking in a general sense (not just comments on this thread). There are people who don`t believe that live music is useful or beneficial for judging the merits of audio components. Some advocate truefulness to the recording source as a more accurate approach.I don`t find that method the better option. Go through the archives and you`ll find more than a few of these advocates.
Regards, |
Csontos,
I imagine we all pretty much have the same goal but different approaches can lead one in different directions down the path toward that goal. I just keep it simple,hear live music and figure out the way to come close to replicating it in your home system.Everyone has their own way, that`s mine.
Regards, |
