It never happened to me that the source (digital) + amp had insufficient gain.
I was considering an optimal case with a single source, if more sources are present, it is obvious the need for a selector.
Obviously is the other way around. Even with more wire and components, the system SOMETIMES sounds better.
Oneself should ask why.
Assuming that the power amp is able to coope with the input level, the most obvious answer is that the source LACKS harmonics, has a poor output stage and other deficiencies that benefits from another active stage after it, this is especially the case when a tube preamps is found to improve everything.
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OK, I think I see where you are going with your reply to me.
Let's see if I understand you.
I did not read all of the link you posted, but it appears that:
1. You hear the device as very superior to most or all that you have listened to?
2. You are still experimenting with modifications?
3. All discrete in the audio path - no op amps?
You said that with op amps, remarkably good results are possible, but that you, personally, would require extreme effort to make it happen.
Lets examine this more closely please:
You determine the excellent result of your unit by recorded source material.
Let us, for example, replace that test unit of yours with the cheap IRD unit up for discussion in my previous post.
Let us assume that it fulfills the outcome of a possibly very good unit as you pointed out that such is a possibility.
What would you think likely, the differences would be?
I ask because you are referring to your musical hearing abilities to qualify what superior results should be.
Consider that source material will pass through the record chain, monitoring included, with op amps often in use, as well, many other questionable circuits.
Now take your pre amp or other system amplification components, replace the recording venue's amplification units with yours.
It is obvious that determining quality of amplification in the context of SUPREMELY excellent or accurate devices requires a lot of consideration, least of which is the mind of the individual and his developed skill in analyzing such matters.
I have to believe, in spite of the above that a qualified individual can still make a Bona Fide statement regarding quality of sound and that it most likely will measure well.
I am not saying that you are not this person, rather that it is a consideration.
I went off topic here, but it was important considering the many off topic results of the replies.
Who here, can design and package a pre amp that is measurably as perfect as we know how to quantify and receive high praise sonically from orchestral conductors, recording engineers, producers and musicians that are known to achieve excellence in their field?
Back to the topic ss/tube, so please give me some examples of ss or tube that meet that criteria.
Since those potential offerings will undoubtedly be met with various opinions, no doubt the very subject of the ss versus tube design will enter into the discussion, hence my original post.
Exactly. I want to know why this is possible. Truth is we still know very little, with experience we may know the How but the Why is still elusive- at least for me. Maybe I can learn something reading this thread.
Phil,
I have been designing, building and selling full preamps for around 35 years. I started with discrete ss designs, and they were successful in the 70's. I also did a lot of modifications to commercial gear, which gained me a lot of expereince in how other designers thought and acted. But around 1978 Ihad a Lux CL35 preamp in for modification, the first one I had worked on. I did the normal things I had done to many ss preamps, and we using in my own ss preamps. The result was magical, and I had what I considered a (little jokingly) a "religious experience".
Ten years after that experience, I proved to myself that I much preferred audio electronics to have no negative feedback (NFB), which is my second key design axiom ever since.
Since then I have played with opamp preamps for a budget product line, but to my ears they always sound "flat" and lacking musical life, and not worthy of my brand name.
They can be very accurate and low distortion via measurement, but listening gives them away.
Why? The key point IMO is that all opamp design is based around the concept of using as much NFB as possible to reduce distortion and while it does reduce MEASURED distortion, but there goes the music. We even use a chip in our JLTi PhonoPre, but it's not an opamp and we use NO NFB with it. That offered better performance for the $$ than we could do ss discrete, and at a far lower price than a properly done tube phono stage.
It's not so hard to get good performance these days with chips, even opamps, but to go the extra steps to be great, I find the job much easier with tubes.
Regards, Allen
I have been designing, building and selling full preamps for around 35 years. I started with discrete ss designs, and they were successful in the 70's. I also did a lot of modifications to commercial gear, which gained me a lot of expereince in how other designers thought and acted. But around 1978 Ihad a Lux CL35 preamp in for modification, the first one I had worked on. I did the normal things I had done to many ss preamps, and we using in my own ss preamps. The result was magical, and I had what I considered a (little jokingly) a "religious experience".
Ten years after that experience, I proved to myself that I much preferred audio electronics to have no negative feedback (NFB), which is my second key design axiom ever since.
Since then I have played with opamp preamps for a budget product line, but to my ears they always sound "flat" and lacking musical life, and not worthy of my brand name.
They can be very accurate and low distortion via measurement, but listening gives them away.
Why? The key point IMO is that all opamp design is based around the concept of using as much NFB as possible to reduce distortion and while it does reduce MEASURED distortion, but there goes the music. We even use a chip in our JLTi PhonoPre, but it's not an opamp and we use NO NFB with it. That offered better performance for the $$ than we could do ss discrete, and at a far lower price than a properly done tube phono stage.
It's not so hard to get good performance these days with chips, even opamps, but to go the extra steps to be great, I find the job much easier with tubes.
Regards, Allen
I am very happy to hear you are so confident with your own opinions to lable mine as "factually inaccurate". I call on historical usage of the word "preamp" to back my case, devices to amplify phono, tape, tuner and other input signals have been known as "preamps" since before WW2.
But never the less, your statements are just opinions and as such you are entitled to them, as I am entitled to mine without being "explained to" in a manner more appropriate to on old school schoolmaster to a 7 year old argumentitive boy in such a direct, and may I say, rude manner.
Regards, Allen
I recently compared a good sounding ss discrete preamp with a single stage common cathode tube preamp. The tube measured much worse than the ss preamp but it sounded better to 'our' ears. (I had some friends over to see if they could hear any difference) Bass on both was good but the tube had more 'life' in the sound and HF had more 'air' around the instruments.
Doesn't mean that all ss preamps are like this one and by itself it is a pretty nice sounding preamp.
However I might add that my last experiment with a tube preamp with negative feedback did sound worse after I applied NFB. It measured better after NFB. Maybe I didn't do it well ....so it probably boils down again to 'how' it is applied !
Doesn't mean that all ss preamps are like this one and by itself it is a pretty nice sounding preamp.
However I might add that my last experiment with a tube preamp with negative feedback did sound worse after I applied NFB. It measured better after NFB. Maybe I didn't do it well ....so it probably boils down again to 'how' it is applied !
Low Cost? They want almost $700 for it. In the context is DIY Audio it is about 3x over priced.
For example I like how they claim that the volume control uses 96 "low noise carbon film resistors" A quick check found that very good ones from a US supplier cost 2.4 cents each. The switch and labor is more
That said I suspect that the preamp is very well made. The photo with the lid remove lets you pretty much know the how it works. There is a good regulated spilt supply and then some op-amps. I'd even suspect they are pretty good op-amps. Logical un-crowded PCB layout too. And the case looks nice. I'd expect, from the photo that the pre-amp sounds as described. The photo shows a very simple design
But, again on a DIY audio forum this preamp is nothing out of the ordinary and is very simple and you should be able to DIY for 3X lower price.
And in the context of commercial audio, distributed through a retail channel it's 3x underpriced
And in the context of commercial audio, distributed through a retail channel it's 3x underpriced
I fully understand that the many talented folks here can make a ss pre like or better than the IRD device and as quoted above, which concerns me, I was attracted to the unit because I will not build a device at this time.
Back to Allen Wright's comments to me:
Hi Allen and thanks for the information which provides enough detail that I would like to ask:
Are you a famous designer or at least well-known within the industry?
Am I able to purchase something from you?
Can any one here offer me, for consideration, an excellent ss opamp-less pre and power amp or recommend some proven design elsewhere?
I initially wished to purchase an integrated, but prefer separate ss pre and pwr.
Allen's comment's reflect what many talented folks have said about op amps, so I see no need to persue a debate about that.
What do you have Allen?
Some examples or a website please?
My post was fact not opinion.
However it was torn out of the thread by moderator Mr. Weldon.
It no longer matters.
Good luck with your business.
Allen Wright's company web site is here: Vacuum State - High End Hifi Equipment
Gain is not he issue , it's energy.
CD players even those with big output drive when run directly has no energy and poor dynamics in contrast to having an additional pre-amp in between.
Which DIY design would you recommend ?
Are you sure about this, isnt the preamp actually creating as what you percieve false dynamics, I use Marantz CD players and they all easily drive any of my amps to full power.
Some CD players have better output stages. Marantz is typically pretty good. Passive has its place as well, and what I would recommend in many cases. However, I too have found that an active preamp can somehow improve things, in many instances. It is probably the length of the interconnect cable from the CD to the preamp or amp that makes the most difference.
NFB does have a way of robbing the signal of its musicality.
General Electric proved why during tests they conducted in the 1960s, yet the audio industry has ignored the results of that testing for the most part.
What they found was that the ear uses odd harmonics to determine the volume/loudness/sound pressure of a sound. Specifically the 5th, 7th and 9th harmonics are used as the loudness cues.
GNFB while overall reducing distortion, tends to enhance these harmonics slightly. Our ears are so sensitive though that 100ths of a percent are audible. This is why the addition of feedback will brighten the sound of almost any circuit, tube or solid state, even though on the bench the frequency response may be unaffected.
Op amps require feedback to set up their gain structure and are thus inherently going to have a brighter sound. Discreet SS is hard to do without feedback, but when it is done right that is when it begins to compete with tubes. Tubes allow zero feedback circuits quite easily.
Like Allen, I have been building preamps for over 35 years. Also like Allen, I prefer fully differential balanced circuits and in both our cases you will see circuits that look a lot like transistor topologies- differential cascodes and effective CCS circuits. BTW excellent CCS circuits can be done with tubes; IMO you need 2 stages to do it right.
When you run balanced, many of the objections to tubes (noise, 2nd harmonic) vanish. The key to quiet tubes once again is a decent CCS.
I find that the more musical the preamp, the more the SS or tube preamps sound alike rather than different. Although I prefer tubes because the distortion structure is less objectionable to the human ear (again, backed up by GE) I am convinced that design, not the device, plays the biggest role; and NFB is simply not going to do it in a good design.
FWIW my preamps are all-tube, can drive 100 feet of balanced interconnect and have only 3 gain stages from LOMC input to high level output, which can drive a set of 32 ohm headphones and is has a direct-coupled output, and no coupling transformers anywhere in the circuit. I mention this only because I expect there are a lot that are viewing this thread that would, prior to this post, have thought that such a thing was something that only transistors could do. In fact transistors would be challenged to do all that I just mentioned, but that is not to say that they cannot. Its *all* in the execution.
General Electric proved why during tests they conducted in the 1960s, yet the audio industry has ignored the results of that testing for the most part.
What they found was that the ear uses odd harmonics to determine the volume/loudness/sound pressure of a sound. Specifically the 5th, 7th and 9th harmonics are used as the loudness cues.
GNFB while overall reducing distortion, tends to enhance these harmonics slightly. Our ears are so sensitive though that 100ths of a percent are audible. This is why the addition of feedback will brighten the sound of almost any circuit, tube or solid state, even though on the bench the frequency response may be unaffected.
Op amps require feedback to set up their gain structure and are thus inherently going to have a brighter sound. Discreet SS is hard to do without feedback, but when it is done right that is when it begins to compete with tubes. Tubes allow zero feedback circuits quite easily.
Like Allen, I have been building preamps for over 35 years. Also like Allen, I prefer fully differential balanced circuits and in both our cases you will see circuits that look a lot like transistor topologies- differential cascodes and effective CCS circuits. BTW excellent CCS circuits can be done with tubes; IMO you need 2 stages to do it right.
When you run balanced, many of the objections to tubes (noise, 2nd harmonic) vanish. The key to quiet tubes once again is a decent CCS.
I find that the more musical the preamp, the more the SS or tube preamps sound alike rather than different. Although I prefer tubes because the distortion structure is less objectionable to the human ear (again, backed up by GE) I am convinced that design, not the device, plays the biggest role; and NFB is simply not going to do it in a good design.
FWIW my preamps are all-tube, can drive 100 feet of balanced interconnect and have only 3 gain stages from LOMC input to high level output, which can drive a set of 32 ohm headphones and is has a direct-coupled output, and no coupling transformers anywhere in the circuit. I mention this only because I expect there are a lot that are viewing this thread that would, prior to this post, have thought that such a thing was something that only transistors could do. In fact transistors would be challenged to do all that I just mentioned, but that is not to say that they cannot. Its *all* in the execution.
This is interesting, but I dont believe it is true, if the distance is kept very short (<1m) with unbalanced connectors.
On the contrary, I believe the quality of the connectors make more difference that the cable itself at such short lenghts.
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