'Digital Glare' - is it really the medium at fault?

[User211]

FWIW I don't think the medium is at fault.

I have a passive pre (high quality Alps RK50), an active valve pre (and recently two solid state active preamps).

I think any glare or roughness can stem from either a naff pre or a naff digital source. What I believe is very cool about passives is that you can rule the preamp out as being problematical or not, since it is essentially doing very little.

Replacing an active pre with a passive and reducing or eliminating glare means the active pre was at fault.

After using the RK50 pot for years, I seem to be into the active valve pre even though I know it is "impure" LOL.

[Macca]

I have CD's & also records that have been transfered from digital {the same ones used on the CD}, they sound different to me.. Any help Macca?

Your talking about CD and vinyl taken from the exact same digital master? I have some too and yes they sound different but that is not surprising as the storage and replay mechanisms are totally different. You have some good RTR machines, have you tried copying a CD to RTR and playing it back? In theory that should banish the digital glare without harming the SQ in any appreciable way.

[User211]

Following on from my previous post I do think there are quite a few digital sources that do suffer from some degree of digital glare or hardness. Which is why finding a good digital source seems to be a much harder problem that it should be.

[Macca]

. What I believe is very cool about passives is that you can rule the preamp out as being problematical or not, since it is essentially doing very little.

Replacing an active pre with a passive and reducing or eliminating glare means the active pre was at fault.

After using the RK50 pot for years, I seem to be into the active valve pre even though I know it is "impure" LOL.

This is exactly my point. I am theorising that the problem is the gain stage in the pre-amp - replace that with a passive pot and suddenly you have CD replay that is just as, if not more listenable than good vinyl replay.
'Vinyl glare' doesn't exist because the output of the phono stage is much lower than that of a DAC or CD player so the active pre does not introduce (what I assume is) distortion or noise. Or both.

Although I am still interested to hear more from Nick as he is suggesting that the problem lies in the player.

[The Barbarian]

Your talking about CD and vinyl taken from the exact same digital master? I have some too and yes they sound different but that is not surprising as the storage and replay mechanisms are totally different. You have some good RTR machines, have you tried copying a CD to RTR and playing it back? In theory that should banish the digital glare without harming the SQ in any appreciable way.

Yes same master.. Your right regarding the R+R..

[Macca]

Yes same master.. Your right regarding the R+R..

I've not tried it myself as I have no RTR (I should really sort that out ) but you are confirming what I have read elsewhere. If the glare originates in the CD player - or is inherent in the medium, then it would transfer to the tape copy. But it doesn't.

[The Barbarian]

I also posted a few years ago that CD itself was not the problem imho, I came to this conclusion because by buying a CD of a certain album that i also had on vinyl, recorded the vinyl onto CD-R then compared the two, the CD-R copy of the vinyl record sounded just like the actual vinyl from whence it came.

My finding were then that the CD-R had no influence over the sound. The shop bought CD {i could not listern to} because it seemed to be too loud.

Neither did i blame the CD Player because the CD-R did not sound loud or any glare..

[lurcher]

Although I am still interested to hear more from Nick as he is suggesting that the problem lies in the player.

Well, I am saying that I have seen the problem in the output stage of CD players, not that there is only one glare, or that its always the same cause. But I do know that in the past that adding unity gain buffers (valve and solid state) to the output of a CD player can make things sound more relaxed. Adding two of them doesn't make it more relaxed, so I believe it was the CD player to what it was driving interface that was the cause of the problem.

Assuming we are agreed on what is glare in this context (which I am not sure we are), I can think of a number of things that could do it, in the case of the Croft, it may be the mosfet that a lot of them have as the output buffer, it could also be the effect of metal film resistors, or it could be the choice of valves, it could also be the pots. Good quality pots are hard to find.

[Macca]

Nick

if there is more than one type of glare and one cause, and there could well be, then that would make some sense. Are we talking about the same thing? It is so hard to describe these things in words. As I said in the OP I can listen to my players for a long time without fatigue - they sound good - but with the passive pre in place there is a step up in quality of resolution. Just like if you reduce the noise floor significantly - a lot of crud that you didn't realise was there before suddenly drops away. That is the effect of the glare (and its removal) that I am talking about. I think John (Welder) missed this point in his post a bit further back.

My Croft pre is all valve btw, no Mosfets, although as it is a budget pre I am sure the pots are nothing fancy.

[lurcher]

My Croft pre is all valve btw, no Mosfets, although as it is a budget pre I am sure the pots are nothing fancy.

Well, I dont know which one you have, but certainly a lot I have seen have a cunning hybrid circuit with a mosfet source follower on each output making what is a lot like a composite anode follower.