Reviewing the Furutec Demag

[Mike Lavigne]

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.

+1

 

[amirm]

I would take the gently romantic comment to mean that the sound tends to be warm instead of on the cool side of analytical and the gently leaning comment meant it was just barely on the romantic side.....

Thanks for helping translate for me Mark. Alas, translation was not necessarily. I can read the same things you did into those words. I suspect that is precisely what the author intended.

Recall my reference to Star Trek language. If I said the ship is moving at "impulse" power versus "warp speed" which one sounds faster? Clearly the latter. Moreover, I need no dictionary to understand those terms. They made complete sense the first time I heard them in the context of the series.

By the same token, these reporters have become exceptionally good at painting pictures with words as above. Take this statement I just read: "The soundstage will take on a more natural presence." I am sure these words translate into the same thing they do for me that that they do for you: the sound stage was of higher fidelity and true to form. Right?

Well, as with Star Trek language above, it is all non-sense. Just because a picture is painted, it doesn't mean it is real. The author is showing mastery of English language, but very poor skills of describing attributes of a real device. BTW, the above quote came from EST contact tweak that Steve just post in another thread: http://www.walkeraudio.com/sst.htm.

Read further into that and you see the opposite language where they describe how you could short out things with that liquid. Now that is a tangible characteristics that is not Star Trek language. Why they could not do the same as they described the positive effects, is the question I raised.

 

[mep]

Amir-I misunderstood your post. I thought you were complaining you had no idea what the author was saying just as you did with RH's comments about "in the groove" and "behind the beat." Sorry for tyring to clariify what I felt these things to mean.

 

[Ethan Winer]

I'm sorry to see Bruce go too.

I agree. Hopefully Bruce will change his mind, I'm sure he has more he could contribute.

--Ethan

 

[garylkoh]

So, because there were doubts to the play-to-play consistency of the LP, and speed differences, etc. I unsealed a new LP today, and made some recordings in 24bit/96kHz.

Take 1 is a brand-new, unplayed LP's first play.

http://www.genesisloudspeakers.com/downloads/Take1.wav

In rapid succession - as long as it takes to lift the arm and re-cue, I made two more recordings:

http://www.genesisloudspeakers.com/downloads/Take2.wav

http://www.genesisloudspeakers.com/downloads/Take3.wav

And then, I lifted the record off, put it down on a clean surface, waited 45 seconds, put it back, and cued it up again for Take 4:

http://www.genesisloudspeakers.com/downloads/Take4.wav

If there is any damage done to the groove walls - the first 3 takes will definitely show it up. Between Take 3 and Take 4 is the same amount of time as it takes to demagnetize the LP.

So, now I flip the album over and make this recording:

http://www.genesisloudspeakers.com/downloads/TakeX.wav

I take the LP off, and demagnetize it and record this final one:

http://www.genesisloudspeakers.com/downloads/TakeD.wav

 

[fas42]

Links are not working, Gary, am I trying too quickly perhaps ...

Frank

 

[garylkoh]

Slow down, Frank. I'm still uploading.....

 

[Orb]

Gary,
this is extra work I know but....
It may be a good idea to do a track that is on the very outside of the LP and the last track on the very inside, the reason being I cannot remember all the theory/explanation but groove modulation difficulties can occur-be different between the two.
It may well be that static/etc has a greater effect on one of those tracks.

Thanks
Orb

 

[garylkoh]

Gary,
this is extra work I know but....
It may be a good idea to do a track that is on the very outside of the LP and the last track on the very inside, the reason being I cannot remember all the theory/explanation but groove modulation difficulties can occur-be different between the two.
It may well be that static/etc has a greater effect on one of those tracks.

Thanks
Orb

Yes, that is the next plan. I'd like to see what Amir and Bruce can see out of these tracks first. I know what I hear, but I'd like to know what they measure

 

[Bruce B]

Yes, that is the next plan. I'd like to see what Amir and Bruce can see out of these tracks first. I know what I hear, but I'd like to know what they measure

I've done some analysis and added some screenshots to show everyone what is happening.

Take 1-4 had approx. 20sec of music. Lining them up and taking a snapshot of 00:00:00:000 and another at 00:00:20:000 produced a variance of 2-3ms. Also taking a snapshot of 1-2, 2-3, 3-4 showed varying degrees of difference as shown


Take 1-2 zoom 5ms
Take 1-2 zoom 1ms
Take 2-3 zoom 5ms
Take 2-3 zoom 1ms
Take 3-4 zoom 5ms
Take 3-4 zoom 1ms

Now, the before and after Demag

Take X and D zoom 5ms
Take X and D zoom 1ms

Now for statistical parameters of Takes 1-4
and

Takes Before and After Demag

 

[amirm]

Looking quickly at summary stats Bruce produced, it seems that the variations from take to take is at least the same if not more than before and after deMag.

 

[Bruce B]

The biggest thing that struck me was the average rms between L/R dropped 17.5dB from before and after Demag.

 

[garylkoh]

The biggest thing that struck me was the average rms between L/R dropped 17.5dB from before and after Demag.

How does that measurement translate to what we hear?

 

[Bruce B]

How does that measurement translate to what we hear?

The tracks would seem quieter, like the volume had been turned down.

 

[garylkoh]

It's not easy to see, but if you overlay the waveforms there are tiny changes. May be Amir can do the same analysis as he did the last time.

Bruce, was there the significant speed differences as with the tracks we did at the meeting?

 

[garylkoh]

The tracks would seem quieter, like the volume had been turned down.

Hmmm..... would that translate to sounding "smoother" if we did not know that there was a volume difference? I thought that was the biggest difference pre- and post- demag.

It boggles the mind that demagnetizing a record can reduce the output by that much. My cantilever isn't even metallic.

 

[Bruce B]

Bruce, was there the significant speed differences as with the tracks we did at the meeting?

The files we did for the meeting I measured out 1:00 minute. These were 20sec, so multiply that by 3 would be about 9ms, which would be a better figure than we had at the meeting.

 

[RBFC]

Could the "demag" procedure leave a residual charge on the surface of the LP, such that the cartridge coils might be affected temporarily? Could this be a reason for the drop in output?

Lee

 

[garylkoh]

Could the "demag" procedure leave a residual charge on the surface of the LP, such that the cartridge coils might be affected temporarily? Could this be a reason for the drop in output?

Lee

It certainly could..... but 17dB is HUGE. I still can't accept it, and I'm reviewing my process to see if it could be testing error. But I'm very, very sure that I didn't touch ANYTHING except the LP, the arm-lift and the tonearm. I didn't even turn the turntable off in between plays, I just took the LP off while the platter was spinning - that's what Roksan recommends.

I need to see if I can find my Talisman, and may be not even touch the LP but to "sweep" it across the surface while the LP's still on the platter.......

 

[Orb]

It certainly could..... but 17dB is HUGE. I still can't accept it, and I'm reviewing my process to see if it could be testing error. But I'm very, very sure that I didn't touch ANYTHING except the LP, the arm-lift and the tonearm. I didn't even turn the turntable off in between plays, I just took the LP off while the platter was spinning - that's what Roksan recommends.

I need to see if I can find my Talisman, and may be not even touch the LP but to "sweep" it across the surface while the LP's still on the platter.......

Just to add.
If it is relating to static charge, I would had thought the demag actually was removing it.
Furutech now have a destat product, also there is the superior vinyl-no carbon black LPs to consider.

I am betting those LPs have a very similar characteristic to the tested LP after demag.
In theory the superior LPs should maintain their performance with repeated plays, curious if demag is doing the same as the Furutech destat product as well
Cough anyone got the destat
Cough Gary you got a new superior no carbon black LP as well

Just for a giggle and I know how many ridicule the CD demag concept (and tbh I have problems myself thinking how it ever could affect CD mech-servo reading), but it is interesting Metronome Technologie modify the Pro2 mech for the purpose of ensuring no CD static charge (seems they think there is or may be parasitic ESD).

Thanks Gary and Bruce for carrying on with this, really interesting to follow.

Orb