I don't have a Quad tuner- if its output is low, you either need to increase that (usually pretty easy, maybe replacing one resistor per channel) or use a line stage with gain. Nearly all modern equipment (CD players, tuners, sound cards/DACs, AV, phono stages) have 2V or higher nominal output. I'm using a unity gain preamp (Heretical) and haven't had any problems playing as loud as I can stand it.
There's no better line stage than no line stage, as Yves correctly pointed out. Most of us can get away with that- if you can't, then you can use a line stage with gain. 6dB is generally more than enough, the old standard of 20-26dB is pretty useless these days.
There's no better line stage than no line stage, as Yves correctly pointed out. Most of us can get away with that- if you can't, then you can use a line stage with gain. 6dB is generally more than enough, the old standard of 20-26dB is pretty useless these days.
I need good sheme (circuit) or project for "High End preamplifier with 6DJ8 (ECC88)"!
If someone has a scheme or project prayed that I would present here.
Here is one non-inverting with adjustable gain. It works very fine with low gain (2...3 x). This sample was built with LM317 as CCS, but a 10 kohms cathode resistor will give similar results, but then the bias voltage must be increased to some 88 V.
THD is 0,07 % with 5 Vrms output voltage to 10 kohms load.
The output impedance is some 0,8 kohms when A = 2 and some 1 kohms when A = 3. The frequency response is flat to some 400 kHz.
This works fine with 6DJ8 as well.
An externally hosted image should be here but it was not working when we last tested it.
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To SY
I started my HI-Fi journey in 1976. At that time, output level of 2 V RMS wasn't typical in any kind of equipment. Should we throw all "unmodern" equipment into a dustbin??
Yes, I use with great entusiasm tube line stages (in a few audio systems)! I can't divide your opinion regarding "There's no better line stage than no line stage". Time ago I participated to a listening session where a CD player was connected to power amp directly or via line level preamplifier. It was not just my opinion that when connected directly, the reproduction seemed strange lifeless with limited dynamic (rather difficult to explain with words). Just to decline any objection, it wasn't my equipment but it was quite expensive! I believe to my ears!
How about frequency response using "passive preamplifier" with potentiometer half-way and not so low capacity interconnect cables? (Oh my God, it can be half-way cause low gain of entire audio chain.)
I didn't feel afraid and never hesitated to modify my Revox, Naka, Quad etc.
I started my HI-Fi journey in 1976. At that time, output level of 2 V RMS wasn't typical in any kind of equipment. Should we throw all "unmodern" equipment into a dustbin??
Yes, I use with great entusiasm tube line stages (in a few audio systems)! I can't divide your opinion regarding "There's no better line stage than no line stage". Time ago I participated to a listening session where a CD player was connected to power amp directly or via line level preamplifier. It was not just my opinion that when connected directly, the reproduction seemed strange lifeless with limited dynamic (rather difficult to explain with words). Just to decline any objection, it wasn't my equipment but it was quite expensive! I believe to my ears!
How about frequency response using "passive preamplifier" with potentiometer half-way and not so low capacity interconnect cables? (Oh my God, it can be half-way cause low gain of entire audio chain.)
I didn't feel afraid and never hesitated to modify my Revox, Naka, Quad etc.
Hello!
I need good sheme (circuit) or project for "High End preamplifier with 6DJ8 (ECC88)"!
If someone has a scheme or project prayed that I would present here.
Thenks
Here it is:
http://www.audiodesignguide.com/ba/prehls.jpg
http://www.audiodesignguide.com/ba/prehlc.jpg
http://www.audiodesignguide.com/ba/prepss.jpg
http://www.audiodesignguide.com/ba/prepsc.jpg
Good luck!
Three likely possibilities:Fidelity Research said:
1. The pot was too high in value or the output cable had too much capacitance, so you added an HF rolloff.
2. The pot was too high in value for the non-linear input impedance of the power amp.
3. You, and others, prefer what the line stage added to the music: a little noise, a little distortion etc.
The fact that the equipment was expensive does not rule out any of these three options. It could even make them more likely!
You left one out. IMO, the most likely.
4. Level matching was not rigorous and the test was sighted.
4. Level matching was not rigorous and the test was sighted.
CD player was directly connected from variable output to power amp without any potentiometer.
About what little noise and little distortion are you speaking??? I didn't mentioned any timbral difference just difference in perceived dynamic!
It was not just my opinion!
I'm not using any passive preamp so I'm not suffering from the possibility of HF roll-off (as described above)!
Probably the defenders of "passive preamps" can run in such a problem!
I'm not prefering nothing, when I'm listening reproduced music I compare it to the sound of real acoustic instruments! For me, Hi-Fi is still close reproduction of "real" sound heard at, let say, concert of acoustic jazz quartet! More close it is, more I enjoj!
You just continue to enjoj your way of listening!
Sorry, I jumped to conclusions! That rules out option 1. Where was the volume control?
Distortion can make sound appear louder, and larger signals will have more distortion (assuming a polynomial transfer function, likely for a line stage) so a bit of non-linearity can boost apparent dynamic range by making the loud bits sound louder.
Distortion can make sound appear louder, and larger signals will have more distortion (assuming a polynomial transfer function, likely for a line stage) so a bit of non-linearity can boost apparent dynamic range by making the loud bits sound louder.
Indeed, a sub 1dB level mismatch will almost always be perceived as an "improvement" in clarity and dynamics rather than a level change. As you say, a little distortion or compression will also "enhance" perceived dynamics. There's also the question of predisposition and necessity of control before making conclusions, but we won't go there.😀
It is not just your opinion. This is why many prefer using active preamps, particularly with digital sources. Not really sure why this is so. Most likely has something to do with high levels of unfiltered RF noise and it's effect on power amps. This is also clearly system dependent - a tube power amp doesn't seem as fussy in this regard. Yes, it is a bit of a mystery and building an active line stage which rivals a passive in transparency is far from trivial.
Another mystery is why the deaf are always the most vocal 🙂
Dear SY/DF96,
You will allow some more heresy from my side!
Can you kindly explain to me why a low output MC cartridge connected first to head amp and then to phono tube RIAA preamp retrieves more information from vinyl disc and sounds better than when directly connected to the same tube phono preamp???
Kindly, let the story about level or impedance mismatch out! (I'm neither child nor novice).
I'm talking what I'm hearing in my system.
Oh, I forgot, head amp uses semiconductors (a lot of them) and (holly sh..) tantalum capacitors, eight of them! Probably you consider that it can't „work“ and assume that I'm enjoying some more noise and some more distortion. I will be glad to put some J.S.Bach Suite in E minor BWV996 and Suite in C minor BWV997 for lute/harpsichord (Hungaroton SLPX12461) on my turntable for you. Or any LP you like. The difference is best described as a difference when you put new strings on guitar. G is always G, A is always A etc, but with new strings that's another story.
LESS IS NOT ALWAYS BETTER
Nor there is any universal rule(s) like tubes are good semiconductor not or passive RIAA is good but active is simply rubbish.
And finally, kindly help our friend „radio“,who started all this story, to build a decent tube preamp. I am quite shure you will!! Even not using obscure or russian tubes and constants current sources. His wish was to build preamp with 6DJ8. Go, help him!
Little remark: Yes, I do like more reproduction from vinyl disc than CDs. Although after almost 30 years we become accustomed to CD „sound“ .
But there are some guys who think that nothing can come close to the original as master tape....(the same tape recorder with output of less than 2 V RMS which is a reason for use of line level preamp, sic!) (Not every one is using just sound cards or CDs)
You will allow some more heresy from my side!
Can you kindly explain to me why a low output MC cartridge connected first to head amp and then to phono tube RIAA preamp retrieves more information from vinyl disc and sounds better than when directly connected to the same tube phono preamp???
Kindly, let the story about level or impedance mismatch out! (I'm neither child nor novice).
I'm talking what I'm hearing in my system.
Oh, I forgot, head amp uses semiconductors (a lot of them) and (holly sh..) tantalum capacitors, eight of them! Probably you consider that it can't „work“ and assume that I'm enjoying some more noise and some more distortion. I will be glad to put some J.S.Bach Suite in E minor BWV996 and Suite in C minor BWV997 for lute/harpsichord (Hungaroton SLPX12461) on my turntable for you. Or any LP you like. The difference is best described as a difference when you put new strings on guitar. G is always G, A is always A etc, but with new strings that's another story.
LESS IS NOT ALWAYS BETTER
Nor there is any universal rule(s) like tubes are good semiconductor not or passive RIAA is good but active is simply rubbish.
And finally, kindly help our friend „radio“,who started all this story, to build a decent tube preamp. I am quite shure you will!! Even not using obscure or russian tubes and constants current sources. His wish was to build preamp with 6DJ8. Go, help him!
Little remark: Yes, I do like more reproduction from vinyl disc than CDs. Although after almost 30 years we become accustomed to CD „sound“ .
But there are some guys who think that nothing can come close to the original as master tape....(the same tape recorder with output of less than 2 V RMS which is a reason for use of line level preamp, sic!) (Not every one is using just sound cards or CDs)
"Better" is a subjective term. "Retrieves more information" is a slogan. So, no, I can't explain your personal preference in unknown equipment evaluated in an unknown manner, nor account for a slogan. And if you're not judging things level matched and by ear alone (not peeking), you can fool yourself very badly- trust me, I learned this the hard way. It has nothing to do with being a novice, it has to do with getting outside the anti-rational culture of high end audio.
But I can say that most people do not need a line amplifier, and for those that do, a unity gain setup is usually optimal. I describe a very high performance one on my website that, coincidentally, uses an ECC88. But if impedances and distances allow, there is no more transparent line stage than no line stage.
But I can say that most people do not need a line amplifier, and for those that do, a unity gain setup is usually optimal. I describe a very high performance one on my website that, coincidentally, uses an ECC88. But if impedances and distances allow, there is no more transparent line stage than no line stage.
"Better" is a subjective term. "Retrieves more information" is a slogan.
No, "better" is what I described as new strings on guitar and "retrives more information" is no a slogan. It is what you hear, all the small details previously passed unnoticed on a record! Just as effect of new and better cartridge (shall I use this words without your comment?), let say, the one you have on your VPI (do I still remember well?) and Shure M55ED. Am I clear enough??
No, "better" is what I described as new strings on guitar and "retrives more information" is no a slogan. It is what you hear, all the small details previously passed unnoticed on a record! Just as effect of new and better cartridge (shall I use this words without your comment?), let say, the one you have on your VPI (do I still remember well?) and Shure M55ED. Am I clear enough??
To SY
Well, well, well!
Can we say that Guarnieri or Stradivari are rubbish but they just play louder?
Would you kindly match for me the acoustic level of above mentioned violins with some less known?? Why musicians (and not only) all around the world agree about the quality of mentioned violins? Are they really better or it is just a SLOGAN!
Well, well, well!
Can we say that Guarnieri or Stradivari are rubbish but they just play louder?
Would you kindly match for me the acoustic level of above mentioned violins with some less known?? Why musicians (and not only) all around the world agree about the quality of mentioned violins? Are they really better or it is just a SLOGAN!
Yes I had a M75ED in seventies and then I made some progress!
Nothing personally with you or anyone!
I don't understand the analogy. A box of gain takes a one dimensional function and scales it. That has nothing to do with violins, motor cars, jump ropes, or fire extinguishers.
Can we compare the sound of two different musical instruments, perhaps violins??
Can we assume that one of them is Stradivari?
Can we expect that a number of people will agree about a superiority of Stradivari over my first attempt to build a violin??
Can we say that something (Stradivari) is better (than my disaster of violin)?
Can we apply the same term speaking about reproduced music when we consider that something reproduce music much closer to the original than other piece of equipment??
Does the term better still represents subjective term when we speak about your preamplifier and your experience?? (as it represents when you speak about my experience and my preamps)
You are going your way, I'm going my way and you can't say I'm laying about my experience!
When you google "diy audio" you can read following:
quote
A community dedicated to helping everyone learn the art of audio.
unquote
So, once again, kindly help "radio" cause he needs your help (I already made a small effort with some links to useful web pages)!
Less is better when more is unnecessary. If the extra stage performs a useful function, such as a low noise preamp for MC, then fine - more is better. Please don't shout.Fidelity Research said:
I have never said any of the things in the second sentence quoted above. He can speak for himself, but I suspect SY has not said any of them either. You must be confusing us with someone else.
There are universal rules: the laws of physics and mathematics. An added stage with little or no gain will reduce signal-to-noise ratio. An added stage with too much gain (i.e. some line stages) will require attenuation, and can end up reducing SNR too. An added stage will always add distortion (assuming it is not perfect), but we can cope with this if we need the extra gain, impedance matching or frequency filtering it provides. It is astonishingly unlikely that an extra stage will somehow cancel the distortion already introduced by the long chain of electronics from performer to your loudspeakers. So an extra stage which is not required for reasons of gain, impedance matching or filtering will degrade the signal. If it sounds better then you prefer a slightly degraded signal. There is nothing wrong with this, and nothing to be ashamed about; it is a well-known phenomenon first found (IIRC) in the 1950s. The problem is that people are very reluctant to admit it, so they claim that the degraded signal is somehow "better".
PS I listen to both vinyl and CD. I have both valves and semiconductors in my setup. My current phono preamp is a simple one I built some years ago, using opamps and a mix of active and passive RIAA. This is, of course, completely irrelevant to the discussion but relevant to your assumptions about me.
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