I remember one of those discussions in which Peter accused Raul of being an undeclared manufacturer. It was true. Raul's objection seems ironic considering the amplitude response anomalies of magnetic phono cartridges.
Getting rid of the RIAA correction network is a gigantic leap forward in preamp SQ, if it's justified. I suspect it is. Soundsmith claims response to 70KHz and < 10o phase discrepancy in the audio band. There's no such thing a good sounding capacitor. Some aren't quite as bad as others.
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Lew, I'm not a circuit designer, EE, or even a tech for that matter. My comments about ARC and CJ amps come from seeing models with serious reliability problems. This was years ago. My experience with Music Reference is with a preamp, also years ago that was nice. It didn't sound goosed up, rolled off or selling off it's colorations. IMO RAM tubes are the best matched in the business and worth the money, depending on application.
You might be interested in this thread by Roger about OTL amps. Some guy named Ralph (handle Atmasphere) joins in: http://www.audiocircle.com/index.php?topic=126867.0
Regards, |
It's a shame we don't get test reports anymore. The subjective crap we get today is no better than reading an advertisement or a manufactures' glowing description of their product. Remember the days when reviewers were often given the test samples? I think all completely subjective reviews should have a warning label: Abandon all hope - Ye Who Enter Here
1980 Dynevector Karat Diamond, Ruby: http://www.cieri.net/Documenti/Cataloghi/Altri%20marchi/Dynavector%20-%20Moving%20Coil%20Cartridge%20Test%20Reports%20and%20Reviews.pdf |
Jcarr, I've been wondering about tubular boron cantilevers and why no one is using them. I assume they were made by Namiki because Nakatsuka used them in the '80s with the microridge. I don't think he currently uses them with ZYX, although I believe one model has a diamond cantilever like a Dynavector.
Namiki won't make them any more?
Regards, |
Accuphase AC-2 designed by Nakatsuka with tubular sapphire cantilever: http://www.accuphase.com/cat/ac-2en.pdf
Regards, |
Hi Jcarr, Thanks for your reply. Boron tube cantilevers were used on some of the Monster carts, and some had sapphire tubes. They had microridge styli and that's why I assumed Namiki. Maybe they were sourced from Matsushita. Some Technics carts had boron tubes.
The boron tubes cantilevers are tiny and flatten out on the diamond end. They also had a diamond dust coating - not exactly sure about the function, rigidity? Regards, |
*My overall impression was a very grain free and pure sound, but from what I heard I did not get an impression that these had the speed of say a Decca, Ikeda or top flight MC..*
Interesting comment, or impression as the case may be. I haven't heard the SS strain gauge. Years ago I briefly heard the Win SG and my impression was of a sound being somewhat different than what we're used to. Transient response (speed) seemed exemplary in an accurate sort of way rather than having a big overshoot on initial attack and drawing attention to the leading edge, but this was a brief encounter. Lab test reports would go a long way to dispelling all the myths and misconceptions.
Myth - Top flight MCs are faster. Faster than what, average MCs, MMs ? Designs w/o cantilever not withstanding, what exotic MC is as fast as a 205C ? I had a TK10ML2 and it was fast as lightning.
What good does it do for a subjective reviewer to list equipment used in an evaluation, as a basis for comparison? Do you have the same $40K phono stage or cables with built-in filters?
This thread has gone full circle, from top flight HO carts to MCs that are superior. I was unaware of this thread 6 years ago when it began. Raul showed up on VE and proclaimed MM/MI superior. We had a running debate in which I said that neither was necessarily better. Evaluations were completely subjective so it became ridiculous. The word distortion was misused a lot.
Raul performed a great service to the community by reawaking to the potential of HO carts. I doubt if he will show up on this thread once again, for obvious reasons. His contribution is noted. Regards, |
Lew, No apology necessary. I was trying to point out Raul's apparent lack of understanding without stating it again, and I didn't intend to label you as such.
The function of preamp inverse RIAA EQ is to playback a record with flat response, as if the curve was never applied. Within a preamp if RIAA accuracy doesn't apply, as in a different system without reverse EQ, then the comparison is absurd. The SG must be evaluated as a system and RIAA accuracy is part of system response. It doesn't exist as a separate measurement. If you want to compare to a magnetic system, then compare response from cart to pre out - total response which includes RIAA adherence.
Have you ever heard Modjeski's direct drive electrostatics? Just wondering. I haven't. I used to have big mono OTL tube amps for electrostatics. They were designed by Dan Fanny of AHT. Each had 4 high voltage cap tubes and they put out 50KV. We had banks of storage caps wired in series to make the necessary voltage.
To me fast refers to transient response. Some might argue that a phono cart isn't designed to play square waves, nevertheless it seems to reveal quite a bit about response. That's why lab tests have square wave scope photos. Today we don't even get a frequency response/separation graph. Moving mass (cart) tends to correlate with rise time. The SG is said to have extremely low moving mass, but I don't know about the rest of the generator. It's also claimed that conversion of mechanical energy is more efficient with less stray vibrations and jitter. Regards, |
Square waves indicate much more than initial rise time which is indicative of speed. How about the ability to stop, another aspect of speed. Fast and clean is the description. Wouldn't a cart with "superior" transient ability also tend to have less phony sustain? The problem with purely subjective reviews is frame of reference.
"Correct rhythm" (PRaT?) could be as much a table or system aspect as that of a cart. Could it be a friendly anomaly that imparts a live sounding coloration? A lab report hinges the subjective on reality and would tend to keep a professional reviewer honest. Maybe they're not all dishonest, but they all, without exception, have a vested interest. Regards, |
Hi Lew, That explains a lot. It's amazing what the high end consumer will put up with in pursuit of perfection. These half-assed designers do their R & D on the customers dime and then get nominated for sainthood by the press. Not Modjeski specifically, companies like ARC and CJ made giant amps that blew up with regularity. You could pretty much count on it. They run the tubes too hot and apparently don't know how to regulate a circuit.
Modjeski currently sells an electrostatic system for $12K. Hopefully he's learned a thing or two since '79, but I don't know anything about it. That's why I asked.
My AHT direct drive amps were completely reliable. The only time one stopped playing was when a high voltage wire got disconnected from the panels. Fix the wire and it's playing again without a problem. Too bad for us Fanny got out of the audio biz. Regards, |
Hi Jcarr, That's very interesting stuff and the DL-1000A cantilever is a remarkable example of precision manufacturing. However, it appears to be quite different from Technics' boron tube cantilevers and would seem to support the notion that there was more than just one source.
While the Denon diamond mounting method cuts off the bottom tube wall, it appears as if Technics left the entire bottom of the cantilever intact, except for possibly drilling through the bottom wall only.
This is a listing for an EPC-305MC The photo on the bottom right is a close-up of the cantilever/diamond. This can be enlarged like an EBay photo. http://www.audiounion.jp/ct/detail/used/57667/
The cantilever on the Monster cart seems different than both of these, which makes me wonder why something like this could be manufactured 30 years ago, but is unobtainium today. I guess the prospect of making this would be seen as a risky investment in the digital age. Regards, |
Hi Jcarr,
**Comparing the stylus to the cantilever on the Technics suggests that the stylus is v-e-r-y long, and has an ample cross-section (at least 0.12mm by 0.12mm by the looks of it), both of which will add to tip mass. I would expect inferior high-frequency crosstalk performance from this design in comparison to Denon's DL-1000A, as the Technic's extra-long stylus will allow the LP groove to twist the generator torsionally in addition to the normal 45-45 motions.**
If you further magnify the photo the stylus seems to be supported at the base by a conical shaped metal structure, like the top of the Washing Monument protruding from a volcano. The light reflecting off this structure is perfectly straight, suggesting a structure and not glue.
I don't know the 305MC tip mass, but the 205C Mk3 is 0.149mg. Holy vanishing mass Batman!! More likely to rotate compared to the DL-1000A ? Poor high frequency crosstalk in comparison - it looks less likely to rotate. Considering the tube is a much more rigid structure than a rod, the entire cantilever is less likely to twist the generator torsionally, than a more rigidly mounted tip on a flimsier rod cantilever. Separation specs are good on the 205C Mk3. Check out post #8. http://www.hifisentralen.no/forumet/vennetra-der-hifimerker/66200-technics-matsushita-electric-trading-co-ltd.html
These photos aren't easy to locate and I have yet to find a good shot of the Monster tip. Matsushita probably dumped their boron tube technology like Shure dumped their MM operation except for a couple of machines they sent to Mexico for M97 and DJ cart production. Technics even abandoned the 1200, although demand seemed high. Maybe the motor got too expensive to make? Regards, |
This is a group test from '06. There are amplitude plots for Clearaudio Concerto and VDH Grasshopper 3.
I think you'll find it amusing. http://www.highend.cz/old/productpages/clearaudio/testy/2006-09ConcertoGrasshopperHiFiNews.pdf
Regards, |
Hello Comrade, While I'm obsessive when it comes to cantilevers, I'm obsessive compulsive with styli. Before each play I use a soft brush three times from back to front. That's three times only, no more no less. Every other side (sometimes more) I use a firmer bristle black brush with cleaning fluid. With some gain on the preamp so I can hear the results, I brush three times from back to front. If it doesn't sound clean, then I repeat the entire procedure including dry brushing. You know what they say, a clean stylus is a happy stylus.
The Ortofon Candenza carts are interesting examples of voicing styli to cantilevers. Red - aluminum/fine line Blue - ruby/FG70 Bronze - tapered aluminum/replicant Black - boron/shibata The transition from Blue to Bronze seems especially interesting. With the replicant tip they revert back to aluminum. The boron on the Black is paired with the sweet sounding shibata. All of these have response to at least 50KHz (-3dB) and the Black is 60KHz. Regards, |
Comrad Nandric Esq. The VE cart database lists the MC-81 as having a shibata stylus with a beryllium cantilever, and the MC-82 (gold body)as having the VDH stylus. Is this possible? The listing also has the MC-82 as having a boron tube cantilever, which I suspect is the real source of its greatness. [couldn't resist]
Does this story need revision? Is the MIT I the same as the Coral MC-81 or 82? Maybe the database is wrong and the VDH belongs to the 81?
Regards, |
At the end of this MC survey there are 5 amplitude plots. http://www.fastaudio.com/workspace/uploads/downloads/stp_08_10_sd_tonabnehmer.pdf
Is the classic rising high end part of the appeal?
Regards, |
Tubed1, What kind of cantilever does it have, and is it in tact? There's a new guy in Washington state, Andy Kim is said to do nice work. He might be somewhat limited in tip and/or cantilever selection, I haven't used his services.
Of course there's Soundsmith and Axel in Germany. Expert Stylus in the UK is highly respected. Regards, |
Lew, There's a description for each cart and within that description a range of preamp loads are mentioned. I'm not fluent in German either. AFAIK all tests were done per manufacturer recommendations. I was told that Stereoplay uses the Test Factory to plot the carts. They are said to be one of the most highly respected facilities and many manufacturers use them to test their products.
Amplitude response in LOMCs doesn't change much, if at all with loading. What changes is stage and dynamics vs focus and detail. Exceptions to this are loading at or near the cart internal impedance or coreless models with high inductance and low output like the DL-S1. I read of someone loading an OC9II at 20 ohms to tame harsh overtones, but I think that's unusual.
The Koetsu Black has big full bass, sort of like a Grado. As you go up the line the carts sound faster and have response more like other expensive carts. The transition between the Black and Rosewood seems especially revealing. I'm by no means expert in Koetsu, but I don't think the more expensive models are rolled off, and maybe the Black sounds mellow due to the bass?
Regards, |
Now that we're into MCs I think there's one thing everybody should realize. Two samples of the same model will probably be different, and they might be very different. On DIY forum John Curl said he couldn't find two samples of the same model that were the same. He didn't mention what brand(s) he was looking at. Did anybody look at the lab report of the Clearaudio Concerto? Apparently the tip was mounted 10° off and response was really screwed up. It fell off like a rock from 10KHz and the commentary said it was voiced for rock. This is a $3K cart?
Awhile back I opened a thread about Clearaudio MMs. They rolled back the specs for V2 and now they're virtually identical to the AT95. Read what poster Kiddman had to say about high end QC: http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1392385752&openfrom&1&4#1
I'm sure some companies are better than others, but what are your options for getting out of a bad decision or getting rid of a lemon? What if something comes up and you don't have time to play it for months, then find out that it sucks?
MM coils are machine wound and consistency is generally higher. I imagine AT and Ortofon have the best QC in the business regardless of type. Not having a user replaceable stylus/cantilever is a selling point for MCs, but it's also a liability. The coils move with the cantilever and that's why HOMC have such high moving mass. The notion that LOMCs having lower moving mass than MM/MI is a myth. It depends on design.
Thinking about this thread and the motivation that inspired it makes me wonder about recent developments. There was always a self serving aspect of preamp sales, but MM/MI awareness seemed genuine. Now, not so much. Ranking seems contrived. Regards, |
Tubed1, If you want to keep it original and the cantilever/suspension are in good shape, then you should have it retipped with a micro type similar to the VDH 1.
Maybe Nandric could advise you about that. I think he said that Axel has those tips, or similar. You could send it to VDH. If you're in the US that would have to be through a VDH dealer or the distributor. Regards, |
Dgarretson, We last heard about your XP-25 saga with great results from the 20SS. Did you switch back to the ART7?
Your posts bring up the question of cart-preamp synergy. Wasn't your previous unit tubes? Sorry, I forgot what that was (MP1?), a phono stage built into a preamp and modified for MCs?
I think the ART7 is much like the 50ANV. It would be interesting to hear what you say. Regards, |
Lew, I doubt Ralph would be upset referring to Dave's phono stage as being built into a preamp. The MP1 appears to be a full function preamp and we're talking about it.
I just read the manual and it seems to be made for MCs. The gain isn't stated. It's about 55dB? I question the choice of a 12AT7 tube, but maybe any tube on the input would have far too much capacitance for a MM anyway, so it's best suited for a LOMC? Any benefit running it balanced in from your table? What kind of MM stage did you build?
Using a SUT is like using a DL103. If you get it right you're trading detail/resolution for dynamics and musicality. Also, the output of a SUT has a lot of capacitance and you're still going into a MM input. That's my opinion and I'm sticking to it. I like and use both MMs and MCs, but the MCs I like tend to be the accurate variety with extended response. Nandric can keep his Kisiki and other romantic MCs. I'm glad he enjoys them, they're not for me. I want to hear what's on the record, not what some cart designer thinks it should be.
I realize Raul started this thread, but I never gave his rankings much credence. It would be nice to talk about this stuff without someone referring to the Mexican. He's not responding any more. Who cares? Regards, |
There's another aspect that makes former rankings absurd. Loading all HO carts at 100K is not only ridiculous, it's stupid. I brought this up before, but some people don't understand the basics. The only reason preamps give you no selection for HO carts is they think MCs are the only ones that matter. Back in the day there were preamps with selectable loads for HO carts, even continuously variable up to 100K. Varying preamp capacitance is mandatory for properly loading a MM. Today, you're lucky if they even tell you what the shunt capacitance is.
HO carts have inductance as a property of the output. That inductance is often used by the cart designer to compliment the amplitude response. With such a cart, if you stray from the recommended capacitance you're changing the intended response. The inductance of the cart combines with the capacitance. They talk about electrical resonance (Hagerman), but it's nearly meaningless. What you need to know is that combination of inductance and capacitance lowers the mechanical high frequency resonance of the cart. It does NOT act as a low pass filter at electrical resonance and it does NOT cause a phase shift at ER frequency.
Sometimes I wonder how this thread got as far as it did. I know some have read the TNT article Load the Magnets by Werner Ogiers (EE). Nobody understands it? http://www.tnt-audio.com/sorgenti/load_the_magnets_e.html
Regards, |
Nandric, In a word, no. You want to have a pissing contest? Buy a race horse. You seem to equate money invested - accumulated carts with expertise/discernment. If there's any such relationship it tends to be an inverse relationship. I don't collect carts like that. I have about a half dozen at any one time. I sell the ones I'm not interested in perusing and I've sold a few I wish I hadn't. At one point you said your favorites were the Miyabi and Kisiki Goldspot. They are romantic. Would you argue that?
I can't say I'm familiar with all your carts, but I noticed you have a duplication. The Pickering 7500 is the same as the 980LZ - identical. They even take the same stylus. Was this to complete your collection? You collect carts like they're model trains or baseball cards. Those two have different writing on them so it's a keeper?
I listen to them one at a time and I usually have a few set up. I consider my Monster 1000 an accurate cart, as opposed to romantic. Response goes past 100K and it's flat as a pancake. Some Dynavectors have similar flat response. If you like a rising high end that's not a problem with me.
The point of MM loading is getting it to sound the way you like. The fact of the matter is, a MM is much more easily manipulated. With a MC loading doesn't do much more than open the stage and dynamics vs focus and detail. Loading has virtually no affect on amplitude response. If more people knew about the potential of MM carts we'd have better MM phono stages with loading options. Regards, |
Nandric, "However he assumed that I wanted to show off with my collection and was not willing to 'disclose' his own except one single MC cart. From this fact it follows that his judgments about MC carts in general are based on induction and not deduction from wahtever general empirical statement. For such purpose one needs at least two MC carts (grin)."
I told you I sell the ones I'm not interested in perusing. I've sold all the MCs except the 1000. That includes the Kisiki, Koetsu, Sumikos, etc. Does that disqualify me from commenting? I was a high end turntable guy at the busiest US high end store at the time. I set-up and tweaked tables all day long and often after work I would go to customer's homes and tweak their tables. I became familiar with a wide range of carts I never owned. I don't comment about carts I'm unfamiliar with.
What does this have to do with anything? You seem to equate the number of carts currently owned with credibility. Like a subjective reviewer blowing smoke up some manufacturer's ass, it might not have much to do with reality. In the past I gave Raul his due for starting this thread, but that doesn't mean he knows how to load a MM.
In the past couple of years I've come to appreciate MMs much more. At this time I have no desire to buy some overpriced MC. MM coils are wound on a machine and sample to sample variation tends to be less than handmade MCs. John Curl said he couldn't find two samples of a MC that were the same. So rest assured the reviewer's cart is probably different from the one you buy.
The term romantic was referring to your cart preference, not you. But you know this. You're using your slickster lawyer skill to turn it into something else. This thread was more interesting when it was about MM/MI. Maybe we have gone through almost all the great MMs, but the rankings skewered results and I suspect there's more to talk about. Regards,
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Lew, here it is - a solid state replacement: http://amtelectronicsusa.com/productpage12AX7WS.html
Regards, |
Nandric, Once again you misstate what I say, and in this case respond to part of what I say. Perhaps you don't believe Kiddman or doubt John Curl ever said that about MCs? Well he did, but I'm not going to hunt for the quote.
The pertinent part here is size - percentage of the total. A small discrepancy in high output cart has relatively little affect compared to a low output.
I never said one was identical and the other isn't, but you have me saying that. You seem to be trying to turn this into a logical argument about absolutes, but you're assuming a premise not stated. Not all MCs deviate from specs like some others, and most MMs are imperfect.
It's a matter of degree. Did you look at the lab report I linked to about the Clearaudio Concerto? It was horrendously bad, a defective cart for $3K. I don't know how typical this is of Concerto, but the implication was of a rolled off response at 10KHz.
Have you ever compared the 980LZ to the 7500? You can use the same stylus on both. It would be interesting to see if there's a difference, more interesting than this back and forth. Regards, |
Lew, I guess you have your answer regarding tip suitability. A line contact will tend to be more sensitive to SRA, depending on the minor radius or the width of the side contacting the groove. Micro styli are usually even more sensitive. They often have a smaller side profile and even greater vertical contact.
If you're so inclined I think you ought to try 2.0g. Normally with a new cantilever/tip max VTF is recommended, at least at first. If you still can't get it to sound right get in touch with Peter. He's a great guy and stands behind his work. If he makes and sells a whole new stylus assembly, I think he'll be able to figure it out. Regards, |
Nandric, I've read a couple of posts before about carts deviating from published specs. Kiddman mentioned a large premium brand deviating 30% on cart impedance. The implication was, this is a regular occurrence, although he didn't say that in so many words. He also mentioned wild deviations in amplitude response, specifically a rise of 8dB by 14KHz.
Unfortunately, I haven't seen any of these posts mention brands. If someone measures carts professionally, that could be for legal reasons. The offending company could be their client and it would hardly be in their interest to name names. John Curl didn't mention what carts he was using to test. The Concerto with a misaligned tip could be a defective one that slipped by? A cart like that would probably be replaced by the dealer and sent back to the manufacturer, but what if you bought it used? I don't think it's unlikely that someone would buy it new and eventually decide they didn't like it and sell it, not realizing it was defective. The reviewer said it was a rock cart and seemed to think that was the way it was supposed to be.
While no cart is perfect and no two channels are perfectly matched, tolerance defines the realm of acceptable deviation. While 30% difference in resistance is unacceptable, what's acceptable, 5% ? Because the output is so little on a LOMC, it's harder to approach perfection. Any small deviation will result in a greater percentage of difference. I would think that's a big part of the price tag.
Some companies are known for consistency and some of them had certain problems a couple of times which they rectified. Dynevector had a batch of 10X5 that had the channels mislabeled so it was out of phase with itself. The same thing happened in the '80s with the 10X4. I had one of these and couldn't understand why it had no bass. This is an entry level cart and it might have been a subcontractor mistake, but sheet happens. AFAIK, Dynevector is otherwise said to be very consistent in QC.
If anyone has anything to add to this dissertation, please do. Regards, |
Jcarr, The Hi Fi news group test looks suspicious. All of the carts have a sharp roll-off at 15KHz ? I think not.
A few years ago Werner Ogiers EE, stated the frequency sweep on that record and Analog Productions are inaccurate. I don't know if they're inaccurate in the same way. Other tests of some of those same carts don't agree with the results.
I think this was the same test lab (Miller) that tested the Concerto. Maybe it made it look worse than it was, but that one was defective and rolled-off at 10KHz. Regards, |
Lew, Have you used your other Ruby on the 505? Compliance should be the same as original, unless Soundsmith also worked on the suspension. Max VTF is 2.0g? Unless specifically told otherwise, I'd increase VTF. Too little can cause loss of bass and momentary mistracking.
I had a DL304 with a broken cantilever. It went to Soundsmith for a level 2 (same) and came back an entirely different cart. It had detail and high frequency resolution it never had before, but it was also extremely sensitive to VTA/SRA. That cart comes with an aluminum cantilever and a special elliptical tip, so it was a more radical change.
Speaking of VTA, have you tried different arm heights? The angle of the stylus with respect to the cantilever might have changed. I'd try it at 2g or close to it and adjust arm height like it's a new cart. Good luck. Regards, |
Hi Jcarr, My response to this following statement about the 305MC seems controversial and I wanted to comment further:
"Comparing the stylus to the cantilever on the Technics suggests that the stylus is v-e-r-y long, and has an ample cross-section (at least 0.12mm by 0.12mm by the looks of it), both of which will add to tip mass. I would expect inferior high-frequency crosstalk performance from this design in comparison to Denon's DL-1000A, as the Technic's extra-long stylus will allow the LP groove to twist the generator torsionally in addition to the normal 45-45 motions."
I think, if the cantilever is very rigid and the tip is overly long and the tip mount rigidity is suspect, then it would be the tip that would tend to rotate and not the cantilever. Use of the phrase "twist the generator torsionally" implies the cantilever.
I'm not saying this is a good thing and perhaps it's not what you meant, but that's how I read it. Regards, |
Hi Jcarr, Yes indeed most interesting.
"Cartridge suspensions should only allow vertical, horizontal and 45-degree flexing modes, but in reality nearly all cartridge suspensions also allow twisting, and if a given suspension doesn't contain a tension wire, fore-aft motion as well."
Microscope photos of grooves show walls that vary from 45°. (BTW for ° sign hit Alt + 248) I've only seen a few such photos, but most seem consistently steeper. It seems to me the motion would be within an arc of 90°. To confuse things further there is also simultaneous vertical angling of the groove. I haven't quite gotten my head around the possibilities, but motion doesn't seem limited to vertical, horizontal and 45° flex modes.
My point about the MC305 was if the stylus mount isn't rigid. I guess it doesn't matter much, performance will still be compromised. I don't have experience with this cart or have lab test to verify if this is actually the case.
Interesting links of the Accuphase carts. The Monster cantilever/tips look like the AC3, but without the beryllium in the middle. About 6 months or so after the 1000 came out there was some kind of change in the cantilever and response was extended past 100K. I think diamond dust coating was added at that time and a change in tip mounting. This was back in '88 and I can't remember the details. Original response was to 75K. Thanks for the calculator it looks interesting. I'll have to check it out.
Hagerman's calculator for HO carts is of limited value for loading purposes. The mechanical performance overwhelms the electrical and shunt capacitance combined with inductance serves to lower high frequency resonance. Someone (not Hagerman) assumed there is a phase shift at electrical resonance, but this appears to not be the case. Phase shift occurs at high frequency resonance. Just thought I'd mention it as there seems to be a lot of confusion about this. Regards, |
Jcarr, My comments are based on an article that appeared in Audio magazine 3/83. It's called Phase Testing in Phono Cartridges, by Kevin Byrne of Ortofon. In the article there are actual plots of amplitude and phase. These are measurements not calculations.
Phase vs amplitude is shown for the MC200 with varying amount of damping. There are also plots for 5 unnamed MMs. The MC200 has a boron cantilever and primary HF resonance is 27KHz. At that frequency there is a phase shift approaching 180°. We don't know what the MMs are, but all had phase shift close to 20KHz. The MC200 phase discrepancy extended down to 7 - 8K, The worst case MM phase was down to 1 - 2K.
This is the only measurement of phase vs amplitude I've seen. I have a copy on a PDF. I can't post it here, but I can send it as an attachment on an email. It would be interesting to read your comments. Regards, |
There's an old thread on VE - Cartridge Loading Explained. For anyone interested in this subject: http://www.vinylengine.com/turntable_forum/viewtopic.php?f=19&t=6674&sid=a26d56af50fa28225f39fa0073dbb465&start=60
In response to a comment about electrical models (Hagerman and a Spice electrical model), Werner (same one as on TNT) said: "And both are near-useless as they don't take the (inevitable) cartridge's mechanical resonance and treble losses into account. With MMs this is all happening around 10-20kHz, and electrical resonance (through loading) is used to compensate for this."
"Mechanical resonances and mechanical treble losses (how fast can you wiggle a given mass?) don't show up in electrical models of cartridges. Both phenomena happen between 10 and 20kHz with MM cartridges.
Sadly cartridge manufacturers don't publish the electrical equivalents of their products mechanical properties."
People who used electrical models for loading inevitably had to abandon those results. The part that's tricky is capacitance. As a general rule I keep capacitance to a minimum and use resistance loading as much as possible. In the case of the Ortofon M20FL Super, 53K and around 250pF was preferable to 47K, 400pF. Capacitance lowers high frequency resonance and normally augments treble just as it did in the TNT M97 article, only not as extreme. BTW, the M97 goes through a remarkable improvement with a Jico SAS stylus. Regards, |
I think we like record players because of the differences and the possibilities those differences afford. Not all differences are assets or shortcomings, sometimes they're just different. Different flavors, as Jcarr said.
Understanding something about how cartridges work can enhance enjoyment. Knowing how to load certainly helps, and seeing a frequency response graph can give us a better idea of response, than a purely subjective review without it.
I thought you'd talk about what you like about some of your carts, instead of making another list. We all have our preferences and our personal rankings may or may not coincide with someone else's preferences. Years ago I thought MCs were better than MMs, now I don't think either one is superior. They're different. I tend to like accurate carts, but nothing's perfect and there are other aspects of performance. To each his own. Regards,
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Lew, if you're still interested in a budget phono stage let me know. I have some comparative user reports on the top contenders.
Nandric, if you're still looking for X-1 replacement styli TurntableNeedles.com has what I believe to be an Astatic. Like the Jico replacements it's a straight aluminum cantilever with a bonded tip. #673-DQ. ($38) Jico doesn't have the stylus. Regards, |
Lew, I never herd of them either. Apparently AMT uses matched fets and probably the JetCity as well. I didn't see AMT for sale and I have no idea about any qualitative differences.
Seems like they get mixed reviews on musicians sites, mostly positive as far as I can tell. Some of them loved them and one guy said it eliminated howling and ringing and sounded better the rest of the time. You can buy them direct from Jet City and it won't cost much to find out. The ones in the red pack are high gain.
I'd guess that audiofool tube heads would be the last to accept something like this even if it was better. I don't particularly like those little 12_ tubes and have no use for them, but they might be way better and quieter in a phono pre. Seems to work out for Audpulse. Regards, |
AP, If you're using the line stage section try substituting 12au7 on the output. If you need more gain on phono maybe the high gain Jet City substitute will do it? You'd have to try it. I have no idea if it's appropriate. http://www.diyaudio.com/forums/tubes-valves/67922-marantz-7c-still-good-today.html
Discussion about preamp viability: http://www.diyaudio.com/forums/tubes-valves/20465-marantz-preamp.html
http://www.diyaudio.com/forums/tubes-valves/93159-marant-7c-preamp-diyzone-project.html
Too little gain on phono and too much on line. The line stage seems to be the Rodney Dangerfield part - gets no respect. I think the high gain Jet City pieces are your best hope. You could go out the tape outputs and use it as a phono stage?
Finally - modding and RIAA EQ. http://www.diyaudio.com/forums/tubes-valves/120643-variability-riaa-eq-tube-characteristics.html
Regards, |
One load fits all? HO carts require more attention to loading than MCs. Two of the three variables of electrical resonance, the LCR circuit that interacts with mechanical response, is under your control, or it should be.
As a general rule vary resistance with bright or dull SQ and keep capacitance low initially. Too bright - lower resistance value and visa versa.
If there is a mid treble dip in response making the cart sound distant, you might have to add capacitance. Adding capacitance will lower high frequency resonance and help fill in the dip by augmenting treble. It will also roll off the extreme high end. Judicious application of capacitance while varying resistance will often result in a minimal addition of capacitance.
This was the case for me with the Ortofon M20FL Super. 55K and approx. 250pF did the trick.
I think you might find that optimal load will vary somewhat from preamp to preamp and for different systems. Some carts, especially those designed for 4-ch, might sound smoother than most at 100K. Many carts are unlistenable at 100K with jagged response and wild frequency response variations. Sometimes using 100K and lots of capacitance will mimic a MC rising high end, but that depends on the cart. Regards, |
The Shure V15 replacement styli are not interchangeable. The V15III takes the VN35HE replacement and the V15IV is the VN45HE. It would be easier to see the different models at LP Gear, rather than Jico site. They have a separate category for Jico.
You'll probably get better results with the III or IV models paired with SDS. Dlaloum is probably the world authority on these and it seems they will work better on the higher inductance models due to an unusually low (for boron) resonant frequency.
Regards, |
Back in the day there were variable resistance MM stage preamps. That TNT article I linked to previously, Load the Magnets, has a picture of the back of a Luxman C12 with a pot for resistance. That article is a good one for understanding how this works.
Loading a low inductance MM is a very different proposition than a high inductance cart. A TK9 or 10ML has inductance of 85mH. Here's Hagerman's electrical resonance calculator. You'll see it just before the first graph. Play with the values and see what happens: http://www.hagtech.com/loading.html
85mH/600pF still has electrical resonance past the audio band. A 6mm boron cantilever will resonate approximately 27KHz. With a cart like this you have to load down resistance to make it less bright.
With high inductance carts - 681 (900mH), it's trickier if there are response anomalies like the mid treble dip of the M97. In that case you have to maintain 250pF to keep the dip from worsening, and because it's a dull cart, increase resistance load. 62K/250pF is said to be optimal for that one. A few words of caution: The rest of the article describes electrical properties only and is of limited value for determining optimal load. The mechanical response is of greater value in determining overall response. Best response is getting one to compliment the other. 1) initially keep capacitance as low as possible. Remember total capacitance is arm wires (internal and external) + preamp.
2) with a higher inductance cart (usually) add capacitance only to fill in treble dip. Otherwise, it's just lowering high frequency resonance and rolling off the top end.
Regards, |
Hi 3ox, I think the Acoustat panels can be driven with much lower voltage, but I'm sure the storage caps were banks of 50KV each. Each amp had 4 cap tubes.
This was around 30 yrs ago and I didn't design the amp or know/understand exactly how it was configured. I do remember building banks of storage caps all hooked up in series. Photoflash caps seemed to make a big difference. Apologies if my description is inaccurate. I'm not a tube designer. Regards, |
Lew, These weren't Acoustat amps. Only the transformer and chassis were original. The amps were custom made by Dan Fanny (AHT). I believe 5KV is the polarizing voltage and tube voltage could be higher? The original tubes were some kind of high voltage TV tube and were upgraded. You might be right though, it was a long time ago. Regards, |
Nandric, You neglect the qualifier "that I have seen". I didn't see a statement about having seen all, only those he has seen.
You assume too much. I made no argument only pointed out the discrepancy between your statements regarding joint pipes. I thought perhaps you would enlighten us on this subject, but you chose to argue against Jcarr?
Well, the cantilever must be attached to something and that something is called.......? They're not all the same and the manner of attachment can be quite different which doesn't always facilitate entire cantilever replacement. At least that's how it seems to me, but I'm not Jcarr. Regards, |
Hi Kevin, Sounds like you've done some interesting things, a tube driven fusion reactor? Dan didn't have the phono stage perfected until around '90, the start of an unfortunate decade for vinyl enthusiasts. I was trying to remember what cartridge he used before the Grasshopper, but it eludes me. I only heard his Reference a couple of times before the VDH. It was good but paled in comparison to the sound after. We used to listen at "normal" loud levels and I suppose his continual perfecting of the electronics had something to do with the improvement.
One day I mentioned the arm height was off and I listened while he adjusted it incrementally. The resolution, the sheer fidelity of his system was impressive, if not the presentation. The Acoustats were 2 + 2 - 4 panels per side, a bit too large for full range panels IMO.
Good luck with your return to record playing. May the vinyl gods smile on your endeavor. Regards, |
Nandric, While this "logical" Abbott and Costello routine may or may not be amusing to readers of this thread, perhaps there is a more interesting subject.
You mentioned that you're in possession of Dertonearm's Archon cartridge. What's the scoop? Is it wonderful, the best thing since sliced bread, or just another ho hum $8K cart? Regards, |
Griffithds, Isn't the nonsense you're writing now, language?
"The whole idea of this cartridge design was to replicate a M/C. I feel it accomplished this idea better in the LZS."
Replicate - to duplicate or copy (something) exactly.
You were writing about the sound quality of HZ vs. LZ not output, and the statement is wrong. The "whole idea" of both cartridges was to NOT replicate a moving coil.
Regards, |
Hi Kevin, I think everyone would be interested in your experiences with strain gauge, Stax etc. I'm sitting on the edge of my chair.
Hi Lew, I suspect the very best MM are those with low inductance and high resonant frequency. They're also the trickiest to load. Regards, |
Lew, My comment was about HO MM/MI, the 980LZ is a special case. I remember Raul saying 100 ohms was it, and that was also mfg recommendation I believe. That's about as valid as all HO carts need 47K. Many preamps back then used 100 ohms as the MC load.
The 980 has considerable treble droop at 100 ohms and like a MC, adding capacitance won't do anything. Inductance is too low. Response is better at 1 - 2K. With the stock stylus it won't get any better. This is David Dlaloum's measurements of the Pickering 7500 (same cart) https://sites.google.com/site/zevaudio/turt/cartridge-comparison-list/pickering-xlz-7500-s
I suspect it needs a Soundsmith level 2 or 3 stylus rebuild. If you can get Peter Lederman on the phone he might be able to advise. I think the problem is mostly mechanical. It already has a short cantilever, but a more rigid one might be like using an SAS replacement stylus? Regards, |