Clearaudio MM -- AT-95E and beyond

neobop · « **Reply #500 on:** 27 Feb 2014, 07:55 pm »

A thread on Agon about Clearaudio specs, a guy called Kiddman who tests carts, said that most high end mfg. make them up. I think you'll get a kick out of this:
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1392385752&openfrom&1&4#1

"Come on, nearly all of these manufacturers make up the specs. Measuring lots and lots of high end analog, I've found the specs are dreams and wishes. MC's that show flat but have a rise of 8db by 14khz. Turntables that quote .01% wow + flutter but are really .3%."

Sometimes I read opinions that are so precise and authoritative and are diametrically opposed to another opinion, it makes you wonder if these people are listening to the same cart. Maybe not.

It would be interesting to hear more about specific brands/models.
neo

*Scotty* · « **Reply #501 on:** 27 Feb 2014, 08:56 pm »

Without test records like the CBS series, phono cartridges can't be adequately measured.
None of the important parameters like frequency response, flatness of response curve,channel separation and distortion can be measured.
Deviations from flat response alone can explain a lot of comments in the audio press concerning the sound of phono cartridges.
Scotty

neobop · « **Reply #502 on:** 27 Feb 2014, 11:14 pm »

Scotty,
I don't know who this Kiddman is or if his findings are published. One generally doesn't see testing of that sort on cart reviews today. All this subjectivism leaves a lot to be desired IMO. We're left with mimes giving their impression of how something sounds.

Some of them are a joke and can't be taken seriously. The others are somewhat informative if you've read most of their other reviews and have a frame of reference. But if sample to sample consistency is lacking, what are you spending your money on? What good are reviews?

Lots of people have test records. David has at least a couple of those vintage ones. There are only a couple modern ones currently available, that I know of, although I don't know if all tests would be covered with them. Amplitude response is a very important parameter, but it is one of many. Pick up an old Hi Fi mag from back in the day. You might even see square wave response. Vintage test records are available, just like vintage records.
neo

neobop · « **Reply #503 on:** 13 Mar 2014, 02:40 am »

Saw this on another forum and thought it might be of interest:

It's interesting that inductance and DCR increase as you go up the line, then all of a sudden the TK9 appears. Sorry the size is small, maybe you can magnify from browser tools.
neo

dlaloum · « **Reply #504 on:** 13 Mar 2014, 03:19 am »

Yes well the TK9 / AT24/25 are a completely different beast really....

And with a tapered beryllium cantilever.... Fully torroidal coils (not para-toroidal like the rest of the AT range)

They really were AT's attempt at no holds barred best possible MM at the time.... and I think they came out before the hollow exotic cantilevers appeared on the scene....

Did AT ever produce a cartridge with a pipe/tube cantilever?

I believe the bodies of these cartridges are a magnesium alloy too...

neobop · « **Reply #505 on:** 13 Mar 2014, 02:15 pm »

Tube cantilevers? Not that I can find.

Nakatsuka used them with the Genesis series with microridge styli, so I assume Namiki manufactured them. AT probably sourced the ML from Namiki, but hollow boron was probably too expensive. Nakatsuka always used the finest parts he could find. When he designed the Accuphase MCs in the '70s he used line contact styli and boron I believe. I assume nobody makes tube boron any more. No current cart I can find has it, including ZYX, Lyra, etc. etc.
neo

neobop · « **Reply #506 on:** 13 Mar 2014, 10:20 pm »

I heard about a couple of others, I think there was one with a ruby or sapphire tube. I'm having trouble remembering. It dawned on me that the Accuphase AC3 from the early '80s had a boron tube with a beryllium rod in the middle for strength. That one had an early micro tip. That was the last Nakatsuka Accuphase design. The Monster ones were hollow boron with diamond dust vapor deposited on the outside.

I remember now, the Sumiko Alchemist III and III S HOMC had sapphire tubes and line contact tips. They were the best Talismans IMO, better than the LO. The Shinon Saphic LOMC also had a sapphire tube and line contact. I never heard that one, I imagine it's rare. I can't remember seeing one for sale. If I come up with any others, I'll let you know, but I don't know of any MM/MI with tube cantilevers. I imagine they were phased out in the early '90s - a terrible decade for analog.
neo

*Scotty* · « **Reply #507 on:** 13 Mar 2014, 11:11 pm »

Neo, I went to your gallery and copied a link to the chart and used my browser to enlarge it to improve legibility.
http://www.audiocircle.com/index.php?action=gallery;area=browse;image=96288;size=huge
Scotty

dlaloum · « **Reply #508 on:** 14 Mar 2014, 12:06 am »

Which makes my point... the TK9/AT24/25 tapered beryllium cantilever was possibly the top cantilever ever produced by AT... (the AT150ANV would be the other competitor...)

neobop · « **Reply #509 on:** 14 Mar 2014, 10:20 am »

Thanks Scotty, much easier to read.

David, Whether beryllium is superior to boron is a matter of opinion. I usually like beryllium with ATs, but boron has some advantages, not the least of which is rigidity. The 150ANV is a sapphire rod (not tube), and tracking is said to be inferior to a 150MLX. I haven't heard it, but the guys on Agon who bought one seem to like it after break-in.

You previously mentioned (I forget exactly where) that tapered cantilevers are more rigid. It seems to me that a straight cantilever will be more rigid but have more tip mass. Think of an aluminum cantilever flexing like crazy, wouldn't the tapered end flex more, not less? Beryllium or boron already have weight advantage and I wonder how much better tapering them is.

You have a Grado don't you? What's the deal with the cantilevers, they're telescoping, made in sections? I never liked them until I borrowed a TLZ. That one was rather amazing with vocals. Ella sounded incredibly fluid and elegant, just luscious until a big band came in behind her. Then it fell apart.
neo

dlaloum · « **Reply #510 on:** 14 Mar 2014, 12:59 pm »

I have been hunting down a good low output Grado body - I now have several signature series bodies and an 8MZ as well as a G1+ needle....

Been doing some reading on the grado's - they are definitely not telescoped in the way that the SAS or V15IV are... rather they seem to have some form of internal damping within the aluminium tube, basically it appears that they turn the cantilever into a sort of transmission line, and in a similar way to transmission line speakers, damping is applied along the length of the transmission line.... I am not claiming to understand this!

Wayner or Frank VanA might perhaps be able to shed more light on this....

My impression of the Grado's in general has been one of superb midrange - but coloured response outside of that - I am intending to test this further soon now that I have the necessary bodies and a couple of the better styli...

With regards to tapering - thinking further on it - tapered tubes have advantages in terms of rigidity over straight tubes - in addition to the mass advantages.

But I agree with you that I cannot see that the same rigidity advantage applies to a solid rod (straight vs tapered) - so perhaps the only advantage was mass.

I generically tend to think of Boron and Beryllium as equivalent - I think differences are marginal between the two materials - especially when used in solid rod form.
In tube form - beryllium could be worked as a foil that then got rolled - as per Shure, Boron on the other hand had to be vapour deposited around a core of a different material, and the core was then dissolved away using a solvent that does not affect Boron - this made for a much more expensive process - although it appears that most of the very best (lowest mass) cantilevers of the golden age used this technique (patented by Technics/National/Matsushita).

The foil beryllium method is I think more prone to flex than the vapour deposit boron rod method - and I wonder whether the solid rods (of either material) are perhaps more rigid than the beryllium foil method? Hence the choice by AT to stick with rods in competing with Shure? (trading off mass for rigidity?

The AT20ss I have is exceptionally neutral with negligible midrange trough - and this was AT's weapon of choice against the V15VMR.... It really is a very good cartridge - more neutral than my TK9e.

bye for now

David

neobop · « **Reply #511 on:** 15 Mar 2014, 11:18 am »

What's a good replacement stylus for a TK7E ? Gear sells an ATN22 for $100. Says it's a bonded .2 elliptical - seems a little pricey.
The 7E will have a round plug and I would think it better to have a stylus where the wings fit the sides of the body, otherwise it might rotate somewhat?
I don't know if a ATN12S or 14S, something like that will fit. Chops is looking for a replacement here:
http://www.audiocircle.com/index.php?topic=124493.0

Looking for a LO Grado body? Wouldn't that be a Woodie with a fixed stylus, or maybe a vintage one w/replaceable stylus? BaMorin (marc morin) used to be the resident Grado expert around here. John the Chair Guy was a big Grado fan and used a Gold with a better stylus and a longhorn. The two of them used to wax poetic about the magic. Personally, I didn't relate. To me, they all sound like they have compromised transient response and lose detail when things get complex. Marc said the problem was either wrong arm or feedback. No denying that was a possibility and those vocals were magical.
neo

dlaloum · « **Reply #512 on:** 15 Mar 2014, 12:25 pm »

I had to collect 4 Signature bodies before I scored one that is low ouput (MCX) - I was a bit disappointed with the Gold1 that I purchased new - so I figured if I am to give the Grado family a chance I need to aim substantially higher....

Being unwilling to pay the rate for one of the upper woodies, I am aiming to get close to that level of performance (based on Marc Morin's input) by combining the signature bodies (this gives me a chance to also compare the G1+, MCX, Signature1, Signature8 and the Gold1) - with two of the better styli from that family 8MZ & G1+ - if it seems to have potential I will look at getting a TLZ stylus potentially...

As a long time owner of Quad ELS57 speakers, I really do apprciate midrange done right...

The TK7e fitted with an ATN15ss or ATN20ss becomes quite legendary.

There is debate as to whether the TK7e/su bodies are better than the AT15/20 ones - the generators are the same....

My AT20SLa fitted with ATN15ss is one of my absolute favourite cartridges - I also have a TK7e body, but its electricals are not as tightly matched left to right as the AT20 so I have stuck with the AT20...

I am pretty sure you can fit any of the ATN13/14/15/20 (definitely the 15/20) styli and you may be able to fit an ATN12s or ATS12s with minor mods....

I have a feeling the Signet stylus mount is better than the AT one - heavier too - but it grips the sides of the cartridge body more positively and therefore may in fact be the better alternative - for a stylus transplant that is!

bye for now

David

neobop · « **Reply #513 on:** 16 Mar 2014, 02:37 pm »

Here's an interesting LOMI:
http://www.sound-smith.com/cartridges/hyperion.html

Soundsmith TOTL with low cu and a cactus cantilever. Put a heavy headshell on that 17g arm and see how it sounds. Only $7K.

I seem to remember DaveyW making cactus cantilevers.
http://www.audiocircle.com/index.php?topic=92976.msg925926#msg925926

http://www.audiokarma.org/forums/showthread.php?t=404018

neo

dlaloum · « **Reply #514 on:** 18 Mar 2014, 01:05 pm »

The process of transplanting a naked stylus onto a new cantilever is far beyond my self-perceived level of competence... let alone the tools I have available!

Although I do love the idea of DIY cantilevers

neobop · « **Reply #515 on:** 18 Mar 2014, 04:15 pm »

Quote from: dlaloum on 18 Mar 2014, 01:05 pm

The process of transplanting a naked stylus onto a new cantilever is far beyond my self-perceived level of competence... let alone the tools I have available!

Although I do love the idea of DIY cantilevers

All you need to do is change that perception. I saw an AT ad back in the day and a lab tech was using a micro comparator to align something or other. That's all you need really, that, tweezers, and a bit of Gorilla glue. I wonder what Shure did with all their stuff when they closed shop. Some of it might have gone down to Mexico to make the M97, and they still haven't learned to use it. Maybe the instructions were in English.....

A low power (50X?) industrial scope should do it. I bet you could rig up something for that USB you took the stylus pictures with. I'll have to read that DaveyW thread again, although he might have been making splints. Sourcing tips might be a big investment. Oh well.
neo

neobop · « **Reply #516 on:** 20 Mar 2014, 02:26 am »

On a more serious note I've been thinking about phase integrity and implications. I think David is right about amplitude response, a rising high end, and imaging. In the Ortofon article they claim that superior phase linearity is responsible for spectacular imaging and as the MC200 was successively damped and imaging worsened, phase nonlinearity was the cause. If we look at the graphs, phase performance didn't change much. Best case it extended down to approx. 10K, and worst case to approx. 7 or 8K. More dramatic was amplitude change - rising high end. Maybe the cause is both, but I suspect amplitude response is mostly responsible.

At this time I don't see any way around inductance and electrical resonance lowering the frequency of the phase peak. If you have an inductor in a filter, there's no getting around its presence. Add more elements, inductors, capacitors, whatever, you just have a more elaborate filter.
What happens to phase? Phase is timing. A 180o phase shift is opposite phase like hooking up a speaker or cart pins with the wires crossed on one channel. That's what happens at high frequency resonance. What happens to the sound, does it go forward or back as a result of the intermediate part of the phase event? I'm not sure, I think it goes forward. Maybe it depends on the preamp.

This seems counterintuitive, but one element in a filter can change a loudspeaker driver's phase forward by 15o (with respect to the other drivers or the signal). I'll see if I can look it up to confirm, but I think that's right. High inductance carts tend to be mellow - rolled off because of amplitude response. Perhaps phase response mitigates that to some extent and makes the sound seem like it's still in the room instead of coming from down the street.
neo

neobop · « **Reply #517 on:** 25 Mar 2014, 03:31 am »

Yes, the phase shift is plus. On another old thread we discussed phase and its importance, but I'm not sure of the importance of the difference in these relative amounts of phase shift. Maybe it depends on the mechanical HF resonance as much as the amount of inductance. If a high inductance cart has mechanical res in the audio band, 180 phase shift will be lowered by electrical resonance. It looks like everything above that peak will have negative phase shift and tend to cancel. If HF resonance and inductance is reasonable, the shift will image forward.
neo

neobop · « **Reply #518 on:** 3 Apr 2014, 01:21 am »

I thought the AT-100E and 150MLX shared the same generator. That's what I was told and when I checked they did seem the same. I'm wondering if they changed the 100, or maybe I missed something?

The inductance and impedance is the same. DCR is 530 ohms (150) and 800 ohms (100).
Output is 4mV (150) and 4.5mV (100).

I don't get it. Could the 100 have slightly bigger coils that have the same inductance at 1KHz ?

neo

dlaloum · « **Reply #519 on:** 3 Apr 2014, 02:11 am »

Even within the AT150's there have been variations - the AT150E - 540mH/767ohm, AT150EA 358mH/488ohm (both are Japan only eliptical versions - with purportedly the same body as the MLX)

Within that family of bodies there seem to be 3 differint models

Most of the p-mount versions use 565mH/770ohm and 530mH/660ohm, and the 1/2" versions seem split between 350mH/530ohm, 490mH/770ohm - but the lines are blurred and sometimes one of the other engines crops up where it is not expected!