Reviewing the Furutec Demag

[Orb]

Well, the speed difference can be explained. If the LP is magnetized, it will create an EMF field which will fight the motor, causing speed variations.....

I do not know about that Amir, those motors are pretty hefty but to know one would need to consider the motor-belt design and type, and how heavy the platter is.
Those platters can be a serious weight and in those cases I doubt the motor could be slowed down due to their "industrial" design.
But for some TT I guess it may be possible if TT and motor are not built to excessive standards.

Cheers
Orb

 

[Orb]

I would not be surprised if LP playback were different from play to play. It is a physical medium, and any slight physical, ionic, temperature, etc.etc. difference could be reflected in sound. Some guys speculate that the grooves "melt" slightly from the heat and pressure of the stylus, and some won't play an LP twice over a 24 hour period because of this.

However, it comes down to the same perceptual quandary, are you just hearing a difference, but not necessarily an improvement, just a variation. Many variations are going to be equally good, or not enough different to be meaningful one way or the other. One probably just needs to accept this variation as part of the "error" envelope of vinyl playback and not try to make LP more precise than it is.

I don't really give a rat's ass if the deguass/demag works or not, it is not worth the effort to prove or find out for what appears to be a minor testimonial difference, much less purchase an expensive piece of equipment over it. Money and time better spent in other pursuits. If I were going to add another OC disorder ritual to my LP playing, this would not be the one.

This is why IMO and sorry to keep on about it; the L+R and L-R measurements Paul Miller are interesting.
They take into considerations the critical aspect of reading the information from the LP and includes distortion; which he also mentions how they can affect the sound and soundstage.
While speed and stability can be a factor, any excellent TT should have uncorrected errors under 0.3% (the new SME 30/2 uncorrect speed when tested was 0.13%) with faultless stability (so no variation and again as an example the SME 30/2 was perfect in their testing at Hifinews).

Overall following more recent measurements and investigations such as those done in Hifinews a very good TT/cartridge and also very good mastered LP/vinyl pressing is going to be pretty consistent.

They also did investigation and new measurements relating to tonearms and the affect of resonances; the primary resonance is usually between 250-600 hz but the biggest surprise is the length of decay time.
But compared to the other factors I would not be even too concerned if using a quality tonearm.

One area I remember reading was that only time repeated playing will have a noticable effect quickly is replaying something recorded way above 20khz - example done was a 45khz recording.
These higher fr will wear out very quickly, and a very good modern cartridge can play this but as mentioned this level of information is lost quickly on the LP due to wear.

Regarding Demag, I guess it comes down to the usual discussions and debate whether it is actually doing something, or for some specifically that the claims are wrong and do not fit with electronics/physics (snake oil).

For me, I am interested just if it is actually changing the performance as this provides more insight into the mechanics of LP and the playback system; and anecdotally the benefits may be the same as new super pressed none-carbon LPs.
So if someone hates noise-pops-etc and that recordings cannot be found on a new higher quality pressing, then demag might help.
Anything beyond this IMO is about subjective preference and debate on the mechanics of demag process and results.

Thanks
Orb

 

[Orb]

Unless I am mistaken, I think we have moved on from DeMag to learning about characteristics of LP system. It sure would be fascinating to find audible differences from play to play. Such differences would cast doubt on many tweaks done in analog domain. After all, if you can't reliably repeat the same experiment, then the tweaks may not be at play at all.

So I for one would love to see 5 captures of the same LP. And then may be raising the temps a bit and repeating, etc. We may be breaking new ground here in discovering how this medium works.

If truly interests you, then it might make sense to contact Paul Miller and ask him how much variation occurs for his L+R and L-R measurements on replays.
Otherwise if doing tests yourself to reach a conclusion on how it works, an indepth understanding about the V goove and left and right channel is going to be essential along with aspects of tracking, distortion,resonances,etc.
Also it would mean knowing and measuring the uncorrected speed, or ensuring speed is correct while also measuring or monitoring stability.

But the tests would help identify how much there are changes on replay, if speed and stability is maintained for each play (and on a very good TT this is not an issue) and use of a very good cartridge to ensure information is consistently picked up on the left and right wall of the groove (but knowing this relies upon measurements as done by Paul Miller).
But you definitely need 2 identical LPs, one super clarity and one quality LP both from same stamper to get anything useful.

Thanks
Orb

 

[mep]

Alright, where are we? Sounds like Amir thinks we are done investigating the Furtech and we have moved on to discovering the secrets of how vinyl works. Before we move on, were conclusions drawn as to whether or not the Furtech had an effect or are we stuck with the possibility that any changes that were seen and heard could have been caused by random changes in the vinyl interface from one play to the next?

One message I’m getting from this thread is that those who already didn’t like LPs are having a field day with these little experiments. Amir for one has amused himself to no small degree. Everyone knows that the LP medium is not perfect and nor did it ever pretend to be. I think the flaws have been well documented for many years and yet in spite of its flaws, it still sounds incredible except to those that can’t forgive an occasional pop or tick.
CDs came into the audio world proclaiming they were perfect. And Amir is on record on the forum as saying that he went to an audio store convinced that the sound of his CDs were going to trounce the sound of LPs and Amir was humbled to find out it wasn’t so. So I would ask, what’s really changed since then to make CDs any better? The only thing I can point to is that D/A converters have improved from the original wretched ones. After all, it’s hard to improve upon perfection.

And now we are faced with the reality that CDs are disappearing from the commercial market place and soon they will only be available on-line until they go extinct all together. Soon digital will cease to exist as a physical medium and most people won’t miss it anyway. “Jewel” boxes that came pre-cracked and broken, liner notes whose small fonts were unreadable and crappy artwork to boot.

Ok, let’s get back to discovering the flaws of the LP medium and see what else can be unearthed to show why all those that love the medium are dunderheads.

 

[amirm]

I do not know about that Amir, those motors are pretty hefty but to know one would need to consider the motor-belt design and type, and how heavy the platter is.
Those platters can be a serious weight and in those cases I doubt the motor could be slowed down due to their "industrial" design.
But for some TT I guess it may be possible if TT and motor are not built to excessive standards.

Cheers
Orb

Sorry Orb. That was my attempt at a joke and wanting to see someone catch me. Alas, no one did and I was about to fess up, and I saw your post . The magnetic field we are talking about here would be way, way too small to have such effects.

 

[garylkoh]

I suspect that I know where the speed variation came from. After we played Ella, I switched over to 45rpm to play something Hugh Masekela (the next track on my list). By then, the evening was almost over and Bruce reminded me that I forgot to do a demag comparison. We, we decided to demag Ella and play her again, so switched back to 33rpm. May be the belt stretched, moved over to another part of the pulley, whatever.

 

[amirm]

Alright, where are we? Sounds like Amir thinks we are done investigating the Furtech and we have moved on to discovering the secrets of how vinyl works.

I think that but not for the reason you are thinking. I am saying that the *data* that we are examining appears to be pointing to inconsistencies in LP playback. So to the extent we keep doing that, we are looking at LP as a medium, not the demag process.

Before we move on, were conclusions drawn as to whether or not the Furtech had an effect or are we stuck with the possibility that any changes that were seen and heard could have been caused by random changes in the vinyl interface from one play to the next?

As Spock would say, "the data as yet does not support any conclusions." To get there, we must first determine if our testing and measurement system is working. If play to play is too variable, then all bets are off -- both for measurement sake and accepting people's observations.

I heard one version being slightly harsher and shallower. Putting aside the possibility of placebo on my behalf when examining these files, such differences in my opinion match and exceed differences by such tweaks. I have for example tested interconnect cables blindly and find them to make nearly the same difference here. When the variations in playback and/or testing is that small, the you can't count on the effect of changing any variable.

One message I’m getting from this thread is that those who already didn’t like LPs are having a field day with these little experiments. Amir for one has amused himself to no small degree.

You get those messages because you keep reading an agenda into every post. As long as you have those colored glasses on, you won't benefit from our discussion. I for one, am fascinated but not the way you think. I am fascinated at how much work and energy members are putting into gathering data and helping dissect them. Being a person who engages in these conversations to learn and discuss the technology as opposed to the person, that is fun and interesting to me.

If you put down the colored glasses for a second, you will notice that if I had an agenda to beat down this device or win one side of this argument, I would not have a) volunteered to run these tests and b) confessed of hearing a difference. There is plenty of ammunition to go after me with said results when I was the one who produced them. I am not worried about that since the nature of my involvement here is the search for information. And on that front, there is no smoking gun to use on me .

So please join me in having a good discussion and not worry about the individuals. What I think or don't think isn't going to amount to anything. But us collectively investigating the data, will give us new insights that might form our opinions and create wisdom. I know that is what it does for me.

Everyone knows that the LP medium is not perfect and nor did it ever pretend to be. I think the flaws have been well documented for many years and yet in spite of its flaws, it still sounds incredible except to those that can’t forgive an occasional pop or tick.

CDs came into the audio world proclaiming they were perfect. And Amir is on record on the forum as saying that he went to an audio store convinced that the sound of his CDs were going to trounce the sound of LPs and Amir was humbled to find out it wasn’t so. So I would ask, what’s really changed since then to make CDs any better? The only thing I can point to is that D/A converters have improved from the original wretched ones. After all, it’s hard to improve upon perfection.

I personally have no data that says CD has improved enough to beat LP. Nothing would surprise me to go and hear an LP beat the CD because of that. I heard taps at CES that were mind boggling good. So that also keeps me from saying things that I cannot back up with data or my own ears.

As I have said though, I don't like LPs regardless of whether they are better than a CD. As a technologist, it has always been my job to advance the science and engineering so that the user is ultimately in charge of it, not the other way around. The iPod did that. It put the user in charge of what to hear and when to hear it. I wont' put up with pops and glitches. I won't put up with lack of convenience. That last bit of fidelity if it exists, is not enough to get me to give these other things. And I will keep working at digital to make it as good if not better than LP. If I don't do that, I can't keep the title of engineer .

And now we are faced with the reality that CDs are disappearing from the commercial market place and soon they will only be available on-line until they go extinct all together. Soon digital will cease to exist as a physical medium and most people won’t miss it anyway. “Jewel” boxes that came pre-cracked and broken, liner notes whose small fonts were unreadable and crappy artwork to boot.

I am not sure why anyone would be surprised that after *40 year* CD's life may be coming to an end. I am worried that there are not enough of us to merit a mass market for high fidelity download service for general music. That threat is serious and merits attention from audiophiles far more than the topics we are discussing!

Ok, let’s get back to discovering the flaws of the LP medium and see what else can be unearthed to show why all those that love the medium are dunderheads.

I used to have a boss where when I would write anything for him or to send out, he would always, always first edit the English. I would keep asking him, "but what about what I said?" He would ignore that comment and keep editing it. I can't tell you how much that bothered me. It seemed like he kept criticizing me.

So one day I asked him why he did that. He said his mother was an English teacher and would never let him get away with writing anything that was less than perfect. From that moment on, it never bothered me that we was critiquing my English. I realized that was his style. And that ultimately, what he was doing was good for me anyway in improving my writing.

By the same token, I hope you stop letting our posts bother you the way they seem to be. Think that this kind of investigation and discussion will make you stronger the next time you run into someone like us. And that, it is all about the topic, and never about the person. I don't get a medal if you gave up your LP tomorrow. I do get a virtual one though if you said, "wow, I didn't know that!" As I did when I had my English corrected at times .

So let's go back to examining the data. I will go wherever that goes.

 

[mep]

I suspect that I know where the speed variation came from. After we played Ella, I switched over to 45rpm to play something Hugh Masekela (the next track on my list). By then, the evening was almost over and Bruce reminded me that I forgot to do a demag comparison. We, we decided to demag Ella and play her again, so switched back to 33rpm. May be the belt stretched, moved over to another part of the pulley, whatever.

Gary-Just another example on why you can't trust the analog medium. Those pesky turntables just won't maintain speed if take you take your eyes off of them for a minute. Seriously, I have noticed that some tables will change speed from where you had it set when you go from 33 1/3 to 45 and then back again. Even more likely if you manually have to move the belt to do so.

 

[Gregadd]

This problem existed with contact enhancers. It was difficult to discern if the result was from breaking the connetction and cleaning it or from the contact enhancer itself.

 

[mep]

You get those messages because you keep reading an agenda into every post. As long as you have those colored glasses on, you won't benefit from our discussion. I for one, am fascinated but not the way you think. I am fascinated at how much work and energy members are putting into gathering data and helping dissect them. Being a person who engages in these conversations to learn and discuss the technology as opposed to the person, that is fun and interesting to me.

If you put down the colored glasses for a second, you will notice that if I had an agenda to beat down this device or win one side of this argument, I would not have a) volunteered to run these tests and b) confessed of hearing a difference. There is plenty of ammunition to go after me with said results when I was the one who produced them. I am not worried about that since the nature of my involvement here is the search for information. And on that front, there is no smoking gun to use on me .

Amir-No colored glasses here and I don’t read an agenda into every post. How about these statements of yours:

What thing I am sure of though: LP is not for me . How do you guys put up with all the clicks and clacks? It drove me nuts analyzing these files. I am so used to quietness in digital. And if the mechanical warble is unrelated to using the device, then that is another thing that would bother me. I think I need hazard pay, having had to listen for 3 hours to these artifacts .

Pretty strong stuff and that is why I wrote what I wrote and I hope you can see why I made the statements I did and I stand by them with no rose glasses. And the thing is, I’m fine with all of this. I think this topic has been useful to help get to the bottom of some things potentially. I just don’t harbor any illusions about who likes analog and who doesn’t. Your statements about LPs that I quoted above speak for themselves. I for one don’t need to tint what you said with glasses of any kind.

 

[Orb]

Sorry Orb. That was my attempt at a joke and wanting to see someone catch me. Alas, no one did and I was about to fess up, and I saw your post . The magnetic field we are talking about here would be way, way too small to have such effects.

ROFL sorry, all I can say it was early and my pesky joke mode was still asleep
I get it now, sorry to ruin your joke, always one to ruin the joke who has to have it explained doh and sorry

Cheers
Orb

 

[mep]

Tom-Any ideas on how analog reproduction might get better as a result of these investigations? Ditto for digital.

 

[Ethan Winer]

We don't know that the act of manipulating the LP or recording multiple times would not naturally generate these variations.

That's my bet. Turntables are so variable that it makes perfect sense to me that for five successive recordings with nothing changed, none will null against another. Further, the moment-to-moment timing variations preclude a meaningful null. So that's another test that should be done - record the same thing without demagnetizing, and see if the variations are similar. If so, then that's your answer.

--Ethan

 

[fas42]

my headphones got pressurized by these two clips

Note that the impressive peaks and troughs of that section of the clip are purely arm/cartridge resonances, nothing to do with what's on the disc. The scale on the top is seconds, the period of the waves is about 0.12 secs, which translates to about 8Hz. That will nicely move the diaphragms in and out, but has nothing to do with music!

Frank

 

[Ethan Winer]

[digital] 'capture it all'. hardly.

I'm surprised nobody else picked up on this. Competent digital recording does indeed capture "it all" - within the bandwidth and noise floor determined by the sample rate and bit depth. This is trivial to prove, and has been done countless times. So my question to Mike is what specifically does digital not capture? Not "just listen," or rely on meaningless audiophile terms like "less etched" etc. But what specific physical property do you believe digital misses?

--Ethan

 

[fas42]

But what specific physical property do you believe digital misses

Actually I believe it is the other way around. Vinyl misses the last degree of detail, the edges get smoothed off; it becomes easier to listen to because the ear/brain has less work to do trying to sort its way through the finer detail, and the mind interprets that as hearing more music. The digital adds more detail, but if the finer stuff is distorted to any degree it overloads the ear/brain, which shuts down to some degree and says " I can't hear the music!".

Frank

 

[amirm]

Note that the impressive peaks and troughs of that section of the clip are purely arm/cartridge resonances, nothing to do with what's on the disc. The scale on the top is seconds, the period of the waves is about 0.12 secs, which translates to about 8Hz. That will nicely move the diaphragms in and out, but has nothing to do with music!

Frank

That's a good observation Frank. The peak is actually 9 Hz. So those waveforms in reality are mechanically induced signals.

 

[Mike Lavigne]

I'm surprised nobody else picked up on this. Competent digital recording does indeed capture "it all" - within the bandwidth and noise floor determined by the sample rate and bit depth. This is trivial to prove, and has been done countless times. So my question to Mike is what specifically does digital not capture? Not "just listen," or rely on meaningless audiophile terms like "less etched" etc. But what specific physical property do you believe digital misses?

--Ethan

it's been a lazy Sunday so far for me, so why not take the bait? i'm sure my answer (and your question) could be inserted in almost any thread on WBF to save us the trouble of typing the same stuff over, and over, and over.....

just because you say 'not "just listen"' i'm all about listening, and the first thing i've got to say is 'just listen'. because your question gets quickly answered. but it's not that simple because both digital and vinyl come in all shapes and sizes.

i can list things digital misses; but it's not a matter of vinyl hitting and digital missing. what vinyl hits and digital misses is in terms of degrees. and some digital gets closer to vinyl than other digital. there is no hard cutoff.

you first need to get specific with PCM digital (not SACD or other DSD derivatives) and music that i listen to; which is mostly analog based. then i'll be more specific and consider top level digital hardware and top level vinyl hardware. like in my room.

based on those issues; what digital misses to varying degrees when compared to better vinyl pressing is;

--low-level detail
--decay in notes
--space, sense of hall
--tonal texture and transparency in the mid-range
--fullness and substance
--organic signature of instruments
--chestiness of vocals
--bloom and openness
--bass energy and flow.
--focus and precision

added note; a couple other areas where vinyl does better.

--resolving musical threads and detail during complicated passages
--vividness of presentation--digital is 'muted' in comparison.

again; PCM digital has all these attributes, just not to the degree that i hear them in good vinyl pressings.

 

[fas42]

what digital misses to varying degrees when compared to better vinyl pressing is;

So what are your thoughts on Gary's just completed experiment of comparing high quality analogue with an extra A/D and D/A step in the playback chain, and the results so far indicate that the group of audio enthusiasts couldn't pick the difference?

Frank

 

[Bruce B]

So what are your thoughts on Gary's just completed experiment of comparing high quality analogue with an extra A/D and D/A step in the playback chain, and the results so far indicate that the group of audio enthusiasts couldn't pick the difference?

Frank

people couldn't pick out the differences because they didn't know what to listen for. As you saw, the people that knew what to listen for scored much better. Not every joe off the block picks out these differences unless you show/tell them what to listen for.