Reviewing the Furutec Demag

[Orb]

Thanks Mike
Totally agree with you Mike, hehe I was going to mention some of what you said but removed it from my post.
BTW you mean 0.55-to-10hz and 3.5-to-10hz?

Couple missing from what I understand is the wow-flutter around 4hz, and motor rumble that can be 15hz and upwards, both of which can be a consideration as well for exciting that vibration mode.
That said the compliance data-calculation is from what I understand can be a guideline and not necessarily fully accurate, by this I mean as an example of compliance data, read comment by andorr: http://www.vinylengine.com/library/shure/v15.shtml

That said, these can be affected by modern engineering designs, example dynamic stabilizer as in the link shown above.

Thanks
Orb

 

[Mike Lavigne]

Thanks Mike
Totally agree with you Mike, hehe I was going to mention some of what you said but removed it from my post.
BTW you mean 0.55-to-10hz and 3.5-to-10hz?

yes.

Couple missing from what I understand is the wow-flutter around 4hz, and motor rumble that can be 15hz and upwards, both of which can be a consideration as well for exciting that vibration mode.
That said the compliance data-calculation is from what I understand can be a guideline and not necessarily fully accurate, by this I mean as an example of compliance data, read comment by andorr: http://www.vinylengine.com/library/shure/v15.shtml

That said, these can be affected by modern engineering designs, example dynamic stabilizer as in the link shown above.

Thanks
Orb

 

[Orb]

yes.

Thought so, just wanted to clarify in case it caused some confusion for others.
Thanks
Orb

 

[amirm]

Orb, there is probably energy at those other frequencies that you mentioned there, it's just that it is overwhelmed by the 8Hz wobble. Unfortunately the software I use, which is designed for audio, stops at 20Hz in terms of filtering, other programs probably could do what you're asking ...

Actually if you are talking about Audacity, you can enhance that. Select 16,000 as the filter size and it will go down to 3 Hz. Wish it would go higher as the resolution steps are still too small but you do get more range. Once there, expand the window of the plot horizontally and then move your cursor back and forth to see the values.

The software nicely declares 9 Hz as the peak in that mode.

 

[Ethan Winer]

You're telling us Digital is perfect in that it can perfectly capture an analog event. Now you're backtracking and saying a "competent" digital recording. What does that entail?

I honestly don't know what or why you are arguing. Nothing is perfect, but we can get close enough to not matter. That's all I address, and that's all I care about. And none of this has to do with why people believe they heard a difference after "demagnetizing" an LP, even though the sound clearly has not changed. Nor does this side-track relate to the claim that digital somehow cannot capture the "organic signature of instruments" whatever that is.

--Ethan

 

[Ethan Winer]

disclaimer; as a technical dunderhead it is possible that my understanding of the following may be completely wrong.

i'm a self described technical dunderhead. but with Google i can do a few things.

as you can tell, i'm not a numbers guy.

Then why are you arguing a point that clearly is highly technical? That is, specific details of what digital recording can and cannot capture. I really don't mean to pick on you Mike, but I have seen that claim many times and it's absolutely, indisputably, totally wrong. Which is why my nose gets out of joint every time I see someone claim that.

i do not know why i hear 'more' with analog; but i do.

You're not imaging things. There is more with analog: more noise, more distortion, and a more skewed frequency response. There's also more wow and flutter (turntables and tape recorders respectively). I understand people like those effects, and that's fine. But it takes some amount of technical understanding to realize those are the reasons analog and digital sound different.

--Ethan

 

[Bruce B]

I honestly don't know what or why you are arguing. Nothing is perfect, but we can get close enough to not matter. That's all I address, and that's all I care about. And none of this has to do with why people believe they heard a difference after "demagnetizing" an LP, even though the sound clearly has not changed. Nor does this side-track relate to the claim that digital somehow cannot capture the "organic signature of instruments" whatever that is.
--Ethan

There were 2 digital files that were posted that clearly shows that after demag there was a difference.

Unfortunately this industry has a few where "good enough" is all too common. We see mediocrity in here all the time. Well music matters to me.... audio quality matters to me and I'm going to keep pushing the limits of my hearing and technology to bring better quality music to my clients. I'm through with this thread.

 

[Ethan Winer]

There were 2 digital files that were posted that clearly shows that after demag there was a difference.

I had (may still even have) those two files from John Atkinson. I saw and heard no meaningful difference. Moreover, every time you play an LP it's measurably different due to speed variations and slight mistracking and groove wear. The difference may even be large enough to be audible. Certainly after 10-20 plays (or whatever) the sound will have degraded enough to notice by ear alone, just as happens with analog tape.

So if these are the two files you're referring to, I'm not convinced. Bruce, are you really arguing that plastic can be damagnetized? What about CDs and audio wires as the vendor also claims? Even if microscopic amounts of magnetic material are embedded in the plastic, how could that possibly influence a playback mechanism that is purely mechanical - a needle wiggling in a groove? Even if miniscule magnetism somehow found its way into the photo cartridge, the magnetism is DC! It's clear to me that any perceived sound difference due to "demagnetizing" an LP is exactly that - perceived, but not real and certainly not due to anything related to magnetics.

--Ethan

 

[Ethan Winer]

This deserves elaboration:

Unfortunately this industry has a few where "good enough" is all too common.

I agree with striving for the very best. I really do. For many reasons. But at some point "the best" collides head on with one's bank account. So for most of us that's the limiting factor. Or we have to balance one "better" against another "good enough" based on what gives the most bang for the buck. For example, splitting $5,000 between room treatment and a "good enough" power amp rather than blowing it all on a power amp and having no treatment.

But as a skilled professional mastering engineer, you can afford, and deserve - and need! - better than good enough. I toss out 60 dB as the point where artifacts probably don't matter, often increasing that to 80 dB just to be safe and to account for younger ears than mine. But as a mastering engineer your gear must be at least 20 dB better than that. If your typical mastering chain consists of four pieces in series, the sum of all artifacts needs to be at least 80 dB down. Same for the frequency response of each piece. Further, the music you master will be broadcast on radio going through yet more gear degradation, or played on someone's hi-fi gear that degrades further. So your chain really does need to be not only fully transparent, but 20 to 30 dB better than transparent. Plus, you need to be able to hear details more than most listeners. For them it's just enjoyment. For you it helps make a better product.

--Ethan

 

[fas42]

F = 1000 / 2 x Pi x sqrt ( MC)

Pi = 3.14159
sqrt = square root
C = stylus compliance in mm/N
M = effective mass of tone arm + cartridge in gr

Mike, I thought you didn't like numbers ...

Frank

 

[garylkoh]

Sorry to see you go, this thread actually had the most information in it of any I have seen. Yes, buried after we all blab away, but real facts and files to prove a difference, however, as Amir and others feel, it may not have proved it was simply the demag until we find out the variability of play to play on the LP. If we are seeking truth, we must be prepared for it IMO.

I'm sorry to see Bruce go too. I don't have the gear or ability to make recordings like he does, but I do intend to get to the bottom of the variability of play to play on the LP..... That's where we can all learn something.

 

[fas42]

Select 16,000 as the filter size and it will go down to 3 Hz

amir, thanks for that. It was a rush job, and I didn't investigate further ...

..., so little time ...

Frank

 

[mep]

I will give everyone one guess why Bruce is through with this thread. Just keep your guesses silent so no one gets offended.

 

[fas42]

Tom here in blue. Yes, a difference most profound, even with signals changing phase from positive to negative (that is extreme!), and also a question, is this just the variability of the medium we were seeing from play to play.

Tom, we need to be very clear here. The obvious variation between the 2 takes in the Start files posted by amir is totally due to the arm/cartridge resonance at around 8-9Hz, which will obviously vary per each playing. It has nothing to do with the music on the disc, and is completely inaudible. When I looked at the real meat of the music the 2 takes are almost perfect copies of each other, the only area where there was variation was in a busy section, with lots of high frequency energy. I posted an image of this earlier on.

Looking at the FFT of this particular section, the most obvious difference is that in take 2 the high frequency content had been reduced, not by a major amount, but possibly significant ...

Frank

 

[microstrip]

There were 2 digital files that were posted that clearly shows that after demag there was a difference.

Unfortunately this industry has a few where "good enough" is all too common. We see mediocrity in here all the time. Well music matters to me.... audio quality matters to me and I'm going to keep pushing the limits of my hearing and technology to bring better quality music to my clients. I'm through with this thread.

Sorry to see you are leaving this thread - the files you posted have great potential for analysis - unhappily I am currently too busy to run a few Matlab analysis tools on them.

Please keep up your work for audio excellency - it is the main reason why we audiophiles can enjoy our systems and also enjoy this board. I know of many other recording and mastering engineers who share this taste for excellency, but they do not have the time or will to participate in our debates...

 

[Steve williams]

I think we would all admit that we are thrilled that Bruce takes such an active role here. I have said for years on these forums well before I had ever met Bruce that IMO the best recorded albums to test a system are those from Winston Ma's First Impression Music and his Lasting Impression Music. I have almost all of them and they are superb thanks to Bruce Brown here who did the mastering. For Bruce to have such a passion to settle for nothing but the best for his clients speaks volumes

Kudos Bruce

 

[mep]

I for one am grateful for what Bruce brings us here and the great asset Bruce is outside of this forum. Bruce has certainly been a help to me.

 

[fas42]

Tom, post #222. The scale at the top tells you the number of seconds into the track. Note the 2nd take looks almost identical except on the really sharp bits it's a bit more rounded. That's indicating that there is a bit of a high frequency cut ...

Frank

 

[JackD201]

Bruce exemplifies the "What's Best" way and has the professional accolades to prove it. Why isn't the other guy on the "What's Good Enough Forum" if he doesn't care for seeing others push boundaries?

 

[fas42]

So, to avoid any confusion, what you looked at was the before and after demag, and saw very little difference? I am too tired to think now, better get some sleep.

Yep, spot on. Both traces are the left channel, the upper one is Take1, before demag, and the lower, Take2, after demag. This area is pretty relevant because it is it right in the middle of a very busy spot, and the treble has been reduced just a touch after the demag, going by that section ...

Frank