turntable reviews?

[Frank Dernie]

There is a site that invested in a miniature instrument grade accelerometer and contains lots of interesting measurements on tone arms. I forgot the name. I have one but it is not small enough for this job, maybe woofers (they are quite expensive BTW).

I remember seeing micro accelerometer data in tone arm reviews and wondering why they did it. I can see the point for the engineers designing it, but even then it risks being a classic case of the instrumentation altering the dynamics.
In the end the only thing that matters is if it contributes to cartridge output which it won't if it isolates the cartridge effectively, which ironically means making it as stiff as possible and in one piece is unlikely to be good.

 

[Frank Dernie]

The Ansuz site is something else, plenty of tweeks with the usual BS.

Wow!
Goldmund made a damped gold plated brass optional clamp for their turntable to replace the ally one it came with that cost a few hundred Euros which I always thought the most outrageous price before! The used Goldmund TT I bought had one with it but I haven't compared standard with fancy one. At least it looks like gold!

 

[MrPeabody]

One of the first jobs I was given when I joined Garrard as an engineer with 5 years noise and vibration research experience was to measure the rumble on a turntable using the Bruel and Kjaer analyser I was familiar with.
I really struggled and couldn't get a consistent result but that was what they wanted me to learn.
The TT was on a solid workbench on the 4th floor of the office building which had a carpark between it and the main road yet, as they pointed out, the inconsistent result was because the TT was picking up traffic vibration from that road.
When put on a heavy concrete block suspended from a big frame by an isolation system I got consistent results.
The point they, and now I, was making is that the cartridge output contains a lot of signal from environmental vibration as well as the groove so what a record player actually sounds like depends strongly on where in the listening room it is sited and what sort of support, plus the effectiveness of any built in isolation - a lot of turntables don't have any.
I experimented at home siting my own TT in different places, including in a different room and confirmed both that it makes a difference to the sound and that I preferred the sound with a bit of pickup over total isolation, probably because of the extra reverb it is effectively adding.

What I am getting around to is that the setup and environment the TT will be in make such a big difference - and effective isolation may not be preferred - that any measurements will only eliminate TTs with problems but in no way tell you which will sound to one's liking in use at home.

The only benefit of TTs IME is the ability to tune the sound to taste by choice of cartridge FR and location and isolation to alter the added reverb. I am not sure how universal any test could be for this.

My advice to @amirm would be not to bother since it will raise more questions than it will answer.

Much as I enjoy my record player I consider it a hobby I have decades of experience fiddling with rather than a hifi source.
I have hundreds of LPs but I don't play one often.

That was a very interesting post and I agree that this will be the rabbit hole of all rabbit holes, if Amir decides to start testing turntables, cartridges, tonearms, etc. Among the several fundamental difficulties, there will be the difficulty of isolating the inaccuracies of the playback equipment from the inaccuracies of the equipment used to produce the vinyl disc. Unless the two potential sources of inaccuracy are isolated, any measurements that are taken will be measurements of the complete end-to-end system. To do otherwise and obtain measurements of the inaccuracies of the playback equipment it will be necessary to have a disc with recorded test signals and a set of files that have the same signals, thereby permitting comparative analysis. In order for this not to be folly, there will need to be some way to verify that the test signals recorded on the vinyl disc are essentially perfect, devoid of any inaccuracies that would interfere with measuring the inaccuracies of the playback equipment. This all sounds like a very tall order to me, and in order to do assessments of a technology that serves only hobbyists needs, that was superseded nearly four decades ago by a vastly different approach to the recording and transmission of audio information.

I would however like to see Amir do measurements of at least one of the classic acoustic suspension speakers from the '70s, e.g., the original Advent or later Large Advent or the eventual 5012. Measurements of an older speaker seem more appropriate for a couple of reasons. One, Amir already has the equipment and expertise to do this. Two, there are remaining questions about the potential advantages of the design approach used in those old acoustic suspension speakers, which have never been satisfactorily answered.

 

[MrPeabody]

...in 2021, turntables, tonearms and cartridges are solved problems, and are actually quite good, even for not tons of money. Maybe not quite as cheap as DAC’s, because they’re mechanical. But I but you can get top level performance from a $1,000 cartridge (maybe a $500 or less), and a $1000 or $2,000 turntable with tonearm, and a $400 phono pre.

If by "solved problem" you mean that it isn't necessary to spend a ton of money to get a playback system very nearly as good as the very best, perhaps this is true. I don't have an opinion on it, but what I want to say is that if this is what you mean by "solved problem", I don't object to the use of that phrase. I mention this only because the phrase alludes to perfection, which is to say, that analog vinyl recording and playback is perfected to the point that there are no sonic limitations. That's all I'm saying, that the phrase "solved problem" has a connotation that does not seem applicable to recording and playback systems where audio is recorded in analog format on vinyl platters.

 

[MrPeabody]

How about some wax cylinder player reviews?

Yes, we very much need for @Amir to take some measurements of the inherently superior, original Edison phonograph that was based on cylinders rather than discs, which avoid the inherent distortions associated with digital quantization, and which are even superior to vinyl discs. The reason is that the effective speed of a vinyl disc varies from the outer part of the spiral to the inner part, and the effective speed is even different for the outer wall of the groove vs. the inner wall. These flaws, widely known to be the root cause of several kinds of audible distortion with the cheaper, modern efforts, are avoided by virtue of design with Edison's original invention. Further pertinent is the fact that it had no electrical circuitry whatsoever. Motion was imparted to the spinning cylinder by means of a hand crank and was regulated by way of a sophisticated mechanical method handed down from generations of Swiss watch technology. It was even said that the Edison cylinder phonograph taken to sea could be used to calculate the longitude to greater accuracy than was possible with many of the best ship's clocks of the era, so accurate was the speed of the cylinder. The thermal noise inherent in electrical valves was fully avoided, as were the phase shift distortions that cannot be fully avoided whenever condensers or magnetic field coils are present in the path through which the signal is transmitted from the pickup apparatus to the listener's ear. Amplification is a fundamentally flawed concept, being altogether unnecessary when the mechanical energy produced by moving the needle along the grove is coupled to the air in an appropriately efficient manner. All of this will become perfectly apparent if only we can persuade Amir to perform the necessary measurements.

 

[sergeauckland]

I remember seeing micro accelerometer data in tone arm reviews and wondering why they did it. I can see the point for the engineers designing it, but even then it risks being a classic case of the instrumentation altering the dynamics.
In the end the only thing that matters is if it contributes to cartridge output which it won't if it isolates the cartridge effectively, which ironically means making it as stiff as possible and in one piece is unlikely to be good.

You may remember the Czech-built NAD turntable from the mid 1980s. It had an arm made from printed circuit board material with the arm cables as printed circuit tracks. The arm was quite stiff in the horizontal plane, floppy in the vertical plane and with limited twist resistance. The counterweight had a weird dashpot damper built in that allegedly damped the floppy arm's resonance.

It all actually worked rather well, but failed to convince anyone, so after year or so, NAD reverted to a conventional metal arm tube.

S

 

[Andysu]

I can sense that this thread may rumble on for some time

Oh seems that you are correct page 8. I be interested but I rather do not mind, I rather like the crackle pops on LP.......

 

[Wes]

There is a site that invested in a miniature instrument grade accelerometer and contains lots of interesting measurements on tone arms. I forgot the name. I have one but it is not small enough for this job, maybe woofers (they are quite expensive BTW).

How much are laser interferometers these days?

 

[Andysu]

I saw a post elsewhere another forum. As I was looking for how to measure turntable maybe I didn't add enough keywords but found that a,'laser tachometers' can be used to check the speed of the record and they are cheap which can be used for anything else.

Be here on monday a, dt-2234c+ digital tachometer, cheap wow. I can check the RPM.

 

[dennis h]

There is a site that invested in a miniature instrument grade accelerometer and contains lots of interesting measurements on tone arms. I forgot the name. I have one but it is not small enough for this job, maybe woofers (they are quite expensive BTW).

http://korfaudio.com/blog

 

[John B]

When you get right down to it the performance improvements between components are dwarfed by the noise created by the vinyl itself. The only prudent solution would be for Amir to buy ELP (the laser turntable folks) and update their system with the latest in machine learned corrective algorithms. No rumble, no record wear, its the beginning of a best case scenario. Someone set that IP free!

 

[Frank Dernie]

When you get right down to it the performance improvements between components are dwarfed by the noise created by the vinyl itself. The only prudent solution would be for Amir to buy ELP (the laser turntable folks) and update their system with the latest in machine learned corrective algorithms. No rumble, no record wear, its the beginning of a best case scenario. Someone set that IP free!

Why would there be any influence on rumble in the laser TT?
Any LF vibration from the platter should be picked up by the laser. Yes, the spurious output of the cartridge below 2x Fn will be absent (splendid) but that isn't rumble.

 

[restorer-john]

Why would there be any influence on rumble in the laser TT?
Any LF vibration from the platter should be picked up by the laser. Yes, the spurious output of the cartridge below 2x Fn will be absent (splendid) but that isn't rumble.

Good point. But rumble is traditionally higher in frequency than what you would expect from a DD drive, it's more motor/belt/idler and higher in frequency wouldn't you say? A DD's rumble is going to be bearing/arm related and low enough in frequency to be easily filtered without undue effect on the musical content.

 

[Frank Dernie]

Good point. But rumble is traditionally higher in frequency than what you would expect from a DD drive, it's more motor/belt/idler and higher in frequency wouldn't you say? A DD's rumble is going to be bearing/arm related and low enough in frequency to be easily filtered without undue effect on the musical content.

The point I was trying to make was simply that the laser will be picking up all the vibration on the record surface, both groove and mechanical so using a laser doesn't stop the unwanted stuff being picked up. At least the low frequencies can be more accurate with a laser rather than changed by the dynamics of the mass and compliance of the transducer below its passband.

 

[DVDdoug]

The "rumor" is... Real world laser turntables are noisy.

And with a decent turntable & cartridge you're already limited by the record itself so the only benefit would be zero record-wear.

 

[sergeauckland]

The "rumor" is... Real world laser turntables are noisy.

And with a decent turntable & cartridge you're already limited by the record itself so the only benefit would be zero record-wear.

The Finial Laser turntable had (maybe still has) the problem that any dirt in the groove was read like modulation, not just pushed out of the way like a normal stylus. That made it noisy with real-world records, compared to a normal turntable. It also would read worn records just as badly as a standard stylus, and there's some evidence that a line-contact stylus can bridge the part of the groove worn by a standard spherical stylus, so reduce the effect of wear, which as far as I know, the Finial didn't do.

It's possible today for DSP to process a laser turntable's output to reduce the effect of impulsive noise, and presumably also by steering the laser and averaging over the groove wall, it should be possible to reduce the effect of wear. Whether the development has ever been done, or even whether there's enough of a market for such a device is questionable. One aspect of expensive turntables is that they look complicated and expensive. The Finial laser turntable looked like a big CD player, so hardly impressive visually.

S.

 

[restorer-john]

If the laser turntable (ELP/Finial) had come to market prior to the mass acceptance and uptake of CD, along with onboard realtime pop/click/aberration correction, it may have been a much bigger deal.

When it finally sort-of became available, CD was so established and clearly such a better solution, there was really no point in the laser turntable. In current times, it seems even more ridiculous. The beauty of LPs and playback is the relative simplicity. The laser turntable was the opposite of that.

 

[egellings]

Wow and flutter measuring equipment is probably near extinct these days, since no one outside of TT mfrs would use it. No digital format requires measurements like that, jitter notwithstanding. I doubt if TT reviewers have that equipment.

 

[restorer-john]

I doubt if TT reviewers have that equipment.

They generally don't have standalone test equipment. Fremer was using that Fiekert app for years. It can be done pretty well by the Virtins software suite and the AP has a W&F function.

The issue is the test records themselves- nobody makes a decent one anymore.

 

[egellings]

Never though of software solutions. They could certainly ace those measurements, given a good ADC & software. Software! They should call it hardware! You try writin' some of it!