Completely understandable, but probably an MC pickup is not the ultimate sound source for judging the sound of a MC stage (!!)
What about feeding an MC stage with a passive anti-RIAA-devider network with a high quality D/A source (SACD etc.) or even better directly from a master (tape) ? This would at least eliminate one problem child for purposes of serious listening tests ... ahem ...
This is probably against the sense of an head amplifier, but it would certainly reveal much more issues with little details than a MC cart and an vinyl pressing ever could ...
SY said:
All of the above practices are dependent on the practitioner much more than on the practice in itself.
All the above practices do work, sometimes, when practiced by certain practitioners – but not always, not by all practitioners.
This is my own experience with most of the above practices.
Of course, there is no valid scientific basis to most of the above, save homeopathy. However, the fact that they do work sometimes only reveals some limitations of present day science.
Now, I know that some will negate my experience as invalid and/or unproved scientifically. Some may ridicule me for my experience. That's fine with me. I'm not going to argue about it. I'm not trying to prove anything, nor am I trying to change anyone's view about those matters. I only reported my experience.
Jon Lord said:
There are very few (available at home at least) sources of recorded music that could better a good vinyl record made before the "digital revolution". And using the other than the actual cartridge source for a phono pre-amp sound evaluation is quite useless, IMHO. Interaction between the cartridge and the preamp is not as straightforward as it looks. I've done a lot of work on phono stages in the last year and found that the "lowest noise minimum distortion" approach just does not work all that well. In my current design I provide a possibility for a user to slightly adjust the bias and thus the transfer characteristic of the phono stage (it is a very simple and linear design with one amplification stage, only local feedback and passive EQ) to match a particular setup. It has a fairly "sharp" optimum point for the best sound. And it is usually not the point for lowest distortion measured with a generator. Mind you, the difference is very small and the distortion of my phono stage are fairly low anyway (about 0.05% second order for 10mV input at 1 kHz). It looks to me that if you can compensate somewhat for a low-level non-linearities in the disc-cartridge combination in the phono preamplifier, you can get a better sound overall. This will be completely missed if you just listen to the phono stage from a reverse RIAA network, connected to a line-level source.
Alex
mlloyd1 said:
I can't speak for Dick's exact circuit but if you put a resistor to ground on the pin for the extra distortion cancelling cap, you basicly have a cascoded long-tailed pair with a resistive load . IIRC you get about a gain of 20 per kOhm of R. This amp is ancient enough to also have an offset trim so you could fashion up a servo that doesn't muck up the inputs.
Come to think of it you could probably parallel several of them too and think up lots of other crazy stuff.
Don't forget that I also mentioned master tapes. Even master tape copies diretly played from RtR necessarily sound much better than vinyl, because many vinyl productions were cut from master tape copies instead of the masters. IMO SACD directly mastered from original analog masters sounds more "analog" than any vinyl, anyhow that's not the question here.
The question is, did anybody ever try to feed a MC amp with a RIAA encoded high quality analog source signal and then switched between Line (direct) and MC ?
I doubt, that the MC/Phono chain could win the race. No chance, never ever. If this would be true, how could then vinyl sound better than SACD or any other analog source connected to the line inputs of the pre ???
Good idea. I'd love to hear such a SACD.
Now, provided the master tape didn't go any compression and/or equalization.
Of course – it should be heard with a REALLY GOOD DAC.
As mentioned above – the question is the sound quality of the reverse RIAA stage and its interaction with the stages preceding and following it.
However, such a test is really interesting.
May be, just may be, digital audio CDs (SACDs or whatever may replace it), will sound better than analog. Then we will be left to the mercy of the mixing engineers.
It appears to me that equalization – and more so mixing and compression – are the actual killers of recordings sound qualities.
However, in this thread it may be better to bend our minds on improving the sound of amplifiers, since the work of mixing engineers is beyond our control.
MC pickups are pretty easy sources, because electrically they are dominated by the internal coil resistance and a very small inductance. If this is a problem, let the cartridge stay electrically within the test chain and even put it on the record surface (but without spinning it).
Regarding mechanical effects (e.g. the distortions by the tracking process), especially the second order, these are heavily dependent on the setup and the position of the needle on the record. Regarding the third and odd higher order components, how would you like to compensate for these (except you even increase them).
So for me the lowest noise - lowest distortion approach sounds most reasonable, especially for a commercial design, where a neutral approach always makes a lot of sense, because the amp has to work with many pickups, drives etc. (Another point overseen pretty often).
Jon Lord said:
Second order effects compensation is good enough for me
. However you are absolutely right that these are heavily setup dependant. That is exactly the reason why I made this knob available to the user - to adjust for a particular setup. Actually, one of my customers even made an external control with a large dial for the phono stage, as he has several different cartridges to play with and that gives him a quick and precise tuning for each.Essentially, without this tuning my phono stage could sound at least as good as most "low noise low distortion" units, because it has low noise and fairly low distortion. However with the tuning it can sound better, that's all. And yes, it is a commercial design, first made for MM and now available for MC as well.
Alex
john curl said:Quality direct disc is best, then analog 30 ips tape, then 30ips tape to disc, then 15ips tape, then 15ips tape to disc, everything else is up for grabs!
In the end we are talking about apples and oranges, I have some of your Clearaudio disks, they are wonderful technically, when I want art (yes my subjective opinion) I listen to Furtwangler's wartime Wagner on Magnetophone tape transfered who knows how many times.
I see we have the usual analog anything is superior to digital thing going
anyone hear what a little digital processing can do for original analog master tapes?
http://www.plangentprocesses.com/
ftp://ftp.bestweb.net/aes117.pdf
we had a wonderful talk at the BAS with demos showing analog master tapes vary from poor to just not too good on the wow/flutter scraping IMD modulation front - and that 1st gen masters can be greatly improved by high speed digital processing to substantially remove the IMD
of course even the best vinyl playback is another order worse on this type of time modulation distortion
heads up John - Greatful Dead restorations are employing Plangent
anyone hear what a little digital processing can do for original analog master tapes?
http://www.plangentprocesses.com/
ftp://ftp.bestweb.net/aes117.pdf
we had a wonderful talk at the BAS with demos showing analog master tapes vary from poor to just not too good on the wow/flutter scraping IMD modulation front - and that 1st gen masters can be greatly improved by high speed digital processing to substantially remove the IMD
of course even the best vinyl playback is another order worse on this type of time modulation distortion
heads up John - Greatful Dead restorations are employing Plangent
Greetings...
I just had to jump in here on the source debate....I gave up on my Studer analog tape decks for original master recording after hearing what DSD can do, and today have both 2 track and 8 track DSD recorders. Editing is most difficult, but I never subscribed to the "fix it in the edit" philosophy anyway...I LIKE it the way it was played, and I make my clients suffer their own playing.
PCM VS super tape format??? such as 30 IPS 1/2 inch 2 track, well 192/24 is not too awful gosh bad for PCM, and at 30 IPS the flutter and wow are not much of the usual problem they are at lower speeds, but your getting into head bump region...It is my finding the matter is moot, as each are eclipsed by good DSD recording. What really hurts is running down to Red-Book 16 bit/44.1KHz, yikes it sound s so bad, even a master grade CD, compared to the original DSD files. I can only think that people who still debate the SACD versus CD thing ought to take up some other hobby that does not require auditory discrimination.
At any rate, this is MY humble opinion ... 51 years of recording experience now , started at age 5, oh so long ago.
I have been enjoying this thread for the past year...good educational stuff!
Hi John! Were still freezing in Oregon!
I just had to jump in here on the source debate....I gave up on my Studer analog tape decks for original master recording after hearing what DSD can do, and today have both 2 track and 8 track DSD recorders. Editing is most difficult, but I never subscribed to the "fix it in the edit" philosophy anyway...I LIKE it the way it was played, and I make my clients suffer their own playing.
PCM VS super tape format??? such as 30 IPS 1/2 inch 2 track, well 192/24 is not too awful gosh bad for PCM, and at 30 IPS the flutter and wow are not much of the usual problem they are at lower speeds, but your getting into head bump region...It is my finding the matter is moot, as each are eclipsed by good DSD recording. What really hurts is running down to Red-Book 16 bit/44.1KHz, yikes it sound s so bad, even a master grade CD, compared to the original DSD files. I can only think that people who still debate the SACD versus CD thing ought to take up some other hobby that does not require auditory discrimination.
At any rate, this is MY humble opinion
... 51 years of recording experience now , started at age 5, oh so long ago. I have been enjoying this thread for the past year...good educational stuff!
Hi John! Were still freezing in Oregon!
I didn't want to push it in the direction "analog is superior to digital" or the like. The opposite is the case, but sometimes you have to be diplomatic ...
The best recording technology is available today, but unfortunately lot's of the available quality is waisted by unskilled recording engineers and the conversion to 44.1/16.
IMO nothing analog ever beats a DXD recorded SACD.
Regarding the Plangent process, I was not aware and it's indeed very interesting. The examples are quite spectacular (because the W&F is certainly >>10% on some of the examples they provide), but on the first sight I have still my reservations that a still rather good tape recording (with an overall W&F of let's say 0.2%) can be improved by this process without any negative side effects.
Compare it e.g. with an asynchronous sample rate converter, these might work in dozens of AES papers, but in real life they all introduce loads of jitter, but that's again a different story.
What's now with the A/B test of a MC stage with my proposed setup ? Any additional thoughts ?
I just proposed a feasible way to get things more objective, when it comes to listening and judging MC stages ...
Is there anybody of the "Objectivist" league on my side or am I too radical here ?
Jon Lord said:
"Objective" (as any listening test is subjective anyway) test of MC preamplifier can only be made with MC cartridge playing a vinyl record IMHO. Otherwise we place the preamp in an artificial situation that most likely will give you a wrong impression, it is that simple. And yes, I did try to compare the preamps the way you have suggested. The idea is very old and in my experience it is a waste of time if we talk about a decent quality electronics. Obviously a very bad phono stage can be recognised as such through a reverse RIAA but that is all - in my opinion.
Alex
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