Descartridge
Stereos been berry, berry good to me!
I am also open to a PM.
The best Japanese SLT turntables. A comparison.
- Thread starter Professor Bizzt
- Start date
- Status
I am also open to a PM.
Hello Pio1980,
I notice you have said "E-mail sent regarding" several times, but I am not getting any private messages from you. Are you referring to a PM?
Best wishes, Professor Bizzt
Pio1980
AK Member
Hello Professor,
PM sent clarifying.
Thnx much for posting re the PL-L000/1000A mods, upgrades definitely of interest for owners desiring results comparable to affordable "audiophile" TTs with the LT/auto features of the subject units.
There is a recommended pipe damping mod to the Technics 'S' arm involving applying 1/2" 3-M shrink tubing. Dunno if it's applicable to the shorter straight L1000 arm pipe.
Best!
PM sent clarifying.
Thnx much for posting re the PL-L000/1000A mods, upgrades definitely of interest for owners desiring results comparable to affordable "audiophile" TTs with the LT/auto features of the subject units.
There is a recommended pipe damping mod to the Technics 'S' arm involving applying 1/2" 3-M shrink tubing. Dunno if it's applicable to the shorter straight L1000 arm pipe.
Best!
Tonearm pipe damping and heat shrink
Hello Pio1980,
I don't see anything wrong with using heat shrink to damp any metal tonearm regardless of length, but doing this should be of significantly less benefit on a tonearm like the Polymer Graphite and aluminum tube composite design of the PL-L1000A. Personally I would not bother on a PL-L1000A.
About a year ago I completely dismantled a PL-L1000 tonearm in order to determine the value of damping the tonearm pipe from the inside. I can tell you it was not worth the hassle. Heat shrink would have been a far better choice overall. Heat shrink tubing certainly is a very easy way to damp a tonearm pipe.
UPDATE!!!
It is the right thing to go back and edit what we have written when we discover there are flaws in it.
I have been having visions lately about someone applying heat shrink tubing to their tonearm and melting or damaging something on their turntable. It is for this reason that I am now very leery of recommending this mod to people. I apologize for this oversight.
Best wishes, Professor Bizzt
Hello Pio1980,
I don't see anything wrong with using heat shrink to damp any metal tonearm regardless of length, but doing this should be of significantly less benefit on a tonearm like the Polymer Graphite and aluminum tube composite design of the PL-L1000A. Personally I would not bother on a PL-L1000A.
About a year ago I completely dismantled a PL-L1000 tonearm in order to determine the value of damping the tonearm pipe from the inside. I can tell you it was not worth the hassle. Heat shrink would have been a far better choice overall. Heat shrink tubing certainly is a very easy way to damp a tonearm pipe.
UPDATE!!!
It is the right thing to go back and edit what we have written when we discover there are flaws in it.
I have been having visions lately about someone applying heat shrink tubing to their tonearm and melting or damaging something on their turntable. It is for this reason that I am now very leery of recommending this mod to people. I apologize for this oversight.
Best wishes, Professor Bizzt
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The necessity of state of tune
Hello everyone,
One of the things that has not been mentioned in this thread is how important it is to maintain a high state of tune on these SLT turntables. One has to treat higher-end SLT turntables differently than a simple manual (or even automatic) pivoting arm turntable. They most certainly require your care and attention.
I have read many threads where the owner or someone who has auditioned a higher-end SLT turntable is voicing his opinion on the merits or lack thereof of this or that SLT.
My feeling is this: If an SLT turntable is compromised (and many are) in any way whatsoever, how can these evaluations and or comparisons have any legitimacy?
There are more SLT turntables that are in varying degrees of poor tune than we realize. Indeed every single one that I have worked on, regardless of pedigree, had at least some issues that detrimentally impacted performance. My guess is that most of the SLT turntables sold on ebay for example have issues that need attention.
It is my opinion that these turntables should be gone over very carefully in the same way a respected race car engine builder rebuilds engines. This is not advice to hear myself talk, this is an important issue. If anyone has anything to say about this, it would be great to hear from them.
Best wishes, Professor Bizzt
Hello everyone,
One of the things that has not been mentioned in this thread is how important it is to maintain a high state of tune on these SLT turntables. One has to treat higher-end SLT turntables differently than a simple manual (or even automatic) pivoting arm turntable. They most certainly require your care and attention.
I have read many threads where the owner or someone who has auditioned a higher-end SLT turntable is voicing his opinion on the merits or lack thereof of this or that SLT.
My feeling is this: If an SLT turntable is compromised (and many are) in any way whatsoever, how can these evaluations and or comparisons have any legitimacy?
There are more SLT turntables that are in varying degrees of poor tune than we realize. Indeed every single one that I have worked on, regardless of pedigree, had at least some issues that detrimentally impacted performance. My guess is that most of the SLT turntables sold on ebay for example have issues that need attention.
It is my opinion that these turntables should be gone over very carefully in the same way a respected race car engine builder rebuilds engines. This is not advice to hear myself talk, this is an important issue. If anyone has anything to say about this, it would be great to hear from them.
Best wishes, Professor Bizzt
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Hard bearing versus air bearing mechanical grounding in SLT tonearms
Hello everyone,
Another important aspect that has evaded this discussion is the difference between the hard mechanical grounding (via the carriage rollers) of Japanese SLT turntables, and the soft mechanical grounding inherent to an air bearing SLT tonearm.
I have developed my own opinions, but would rather hear from others first.
Best wishes, Professor Bizzt
Hello everyone,
Another important aspect that has evaded this discussion is the difference between the hard mechanical grounding (via the carriage rollers) of Japanese SLT turntables, and the soft mechanical grounding inherent to an air bearing SLT tonearm.
I have developed my own opinions, but would rather hear from others first.
Best wishes, Professor Bizzt
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Pio1980
AK Member
Definitely something I've contemplated but took a pass on acquiring a ET-2 air bearing LTA to check it out myself, more complications than I really have resources for at this time. The modified Souther SLA-3 LTA is less hassle, shortcomings notwithstanding (Light low mass, soft-ish grounding, ect), and it has been paid for since new nearly 30 years ago.
At least one member has commented on hearing the play in ball-bearing gimbal arms (blurring of ultimate detail resolution IIRC) as a signature sound compared to his ET air bearing LT arm. He has expressed interest in unipivots as the only pivot arms he'd find appealing due to no bearing free play possible. I once owned a Magnapan Unitrack unipivot arm before acquiring the Souther as it's replacement. Each has virtues but the Souther stayed.
At least one member has commented on hearing the play in ball-bearing gimbal arms (blurring of ultimate detail resolution IIRC) as a signature sound compared to his ET air bearing LT arm. He has expressed interest in unipivots as the only pivot arms he'd find appealing due to no bearing free play possible. I once owned a Magnapan Unitrack unipivot arm before acquiring the Souther as it's replacement. Each has virtues but the Souther stayed.
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Pio1980
AK Member
Hello Professor;
Interesting statement on servo LT renovations for best sonic results, thnx for mentioning it. Not many would consider having that done if it all was seeming to work 'normally'. As the Pioneer linear tracking motor is a very special case, do you o'scope the output of the motor's differential power amp for noise as part of the process?
Interesting statement on servo LT renovations for best sonic results, thnx for mentioning it. Not many would consider having that done if it all was seeming to work 'normally'. As the Pioneer linear tracking motor is a very special case, do you o'scope the output of the motor's differential power amp for noise as part of the process?
Plinth physics
Hi Pio1980,
You and I seem to be almost the only people on this thread lately. Where are all the respected engineers responsible for the creation of these interesting machines and the mad scientists who explore the inner workings of them? Oh well, I guess that's asking too much. I guess us amateurs will have to do for now.
I really like your statements on proper plinth design, but please allow me to put this into my own words at the risk of repeating what you have already said. If I'm wrong or have omitted something please tell me. I am only human.
Here are the ideal qualities as I see them without concern for what can actually be achieved or for what is practical:
Plinth:
The plinth (fundamental platform that all components are mounted to) should be infinitely rigid. It should be so rigid that any energy entering it from within or without is reflected back to the source with 100% efficiency.
Since mechanical energy attempting to enter this hypothetically ideal plinth would find no home in it, it would be rejected and reflected back to where it came from. The plinth could not be set into any form of sympathetic vibration whatsoever as it is closed to accepting any energy at all.
The utilization of this perfect material would of course address issues of rigid geometrical relationship of tonearm and spindle. Perhaps a diamond, rhenium diboride, ultrahard fullerite, aggregated diamond nanorod, or some other super-hard material would approximate these ideals.
One should also use this perfect material for the tonearm, headshell, and cartridge body because all mechanical energy should be prevented from traveling any further than the cartridge's elastomer cantilever suspension. This would require a highly advanced cartridge suspension that eliminated or minimized energy reflection back to the stylus via the cantilever as this could adversely impact the already difficult job the stylus has in tracing the record groove.
Why should the plinth have this extreme level of rigidity? Because an otherwise top quality plinth utilizing linear high-bandwidth damping accepting just a portion of a waveform of mechanical energy has already seen the beginning of performance compromise. Under these conditions, it is too late to claim perfection.
Plinth mass, mass distribution, and suspension:
The plinth mass (in conjunction with the suspension) should be large enough so that any mechanical energy of any frequency that the environment is normally capable of generating will be prevented from entering into the infinitely rigid plinth via a suspension tuned to a lower frequency than any frequency normally present in the environment. The plinth mass should also be sufficient enough so as to not react to servo initiated motor torque corrections. The plinth mass distribution should produce a maximum of polar moment of inertia and therefore should be concentrated to the periphery for maximum resistance to torque reactions from within as well as without.
Suspension damping:
The suspension should be damped just well enough to prevent excessive cycles of movement at resonance. Damping further would detrimentally widen the Q of the fundamental suspension resonance and allow more unwanted energy in from the environment.
Suspension linearity:
The suspension should only allow stable, simple, harmonic free, and vertically symmetrical movement of the plinth at fundamental resonance. It should not allow the plinth to move in any manner other than this. Each suspension compliance should not allow frequencies higher than the fundamental resonance to pass through its structure. This often happens with undamped metal springs exhibiting a longitudinal mechanical energy conductance condition at frequencies higher than the suspension/plinth mass fundamental resonance.
Best wishes, Professor Bizzt
Hi Pio1980,
You and I seem to be almost the only people on this thread lately. Where are all the respected engineers responsible for the creation of these interesting machines and the mad scientists who explore the inner workings of them? Oh well, I guess that's asking too much. I guess us amateurs will have to do for now.
I really like your statements on proper plinth design, but please allow me to put this into my own words at the risk of repeating what you have already said. If I'm wrong or have omitted something please tell me. I am only human.
Here are the ideal qualities as I see them without concern for what can actually be achieved or for what is practical:
Plinth:
The plinth (fundamental platform that all components are mounted to) should be infinitely rigid. It should be so rigid that any energy entering it from within or without is reflected back to the source with 100% efficiency.
Since mechanical energy attempting to enter this hypothetically ideal plinth would find no home in it, it would be rejected and reflected back to where it came from. The plinth could not be set into any form of sympathetic vibration whatsoever as it is closed to accepting any energy at all.
The utilization of this perfect material would of course address issues of rigid geometrical relationship of tonearm and spindle. Perhaps a diamond, rhenium diboride, ultrahard fullerite, aggregated diamond nanorod, or some other super-hard material would approximate these ideals.
One should also use this perfect material for the tonearm, headshell, and cartridge body because all mechanical energy should be prevented from traveling any further than the cartridge's elastomer cantilever suspension. This would require a highly advanced cartridge suspension that eliminated or minimized energy reflection back to the stylus via the cantilever as this could adversely impact the already difficult job the stylus has in tracing the record groove.
Why should the plinth have this extreme level of rigidity? Because an otherwise top quality plinth utilizing linear high-bandwidth damping accepting just a portion of a waveform of mechanical energy has already seen the beginning of performance compromise. Under these conditions, it is too late to claim perfection.
Plinth mass, mass distribution, and suspension:
The plinth mass (in conjunction with the suspension) should be large enough so that any mechanical energy of any frequency that the environment is normally capable of generating will be prevented from entering into the infinitely rigid plinth via a suspension tuned to a lower frequency than any frequency normally present in the environment. The plinth mass should also be sufficient enough so as to not react to servo initiated motor torque corrections. The plinth mass distribution should produce a maximum of polar moment of inertia and therefore should be concentrated to the periphery for maximum resistance to torque reactions from within as well as without.
Suspension damping:
The suspension should be damped just well enough to prevent excessive cycles of movement at resonance. Damping further would detrimentally widen the Q of the fundamental suspension resonance and allow more unwanted energy in from the environment.
Suspension linearity:
The suspension should only allow stable, simple, harmonic free, and vertically symmetrical movement of the plinth at fundamental resonance. It should not allow the plinth to move in any manner other than this. Each suspension compliance should not allow frequencies higher than the fundamental resonance to pass through its structure. This often happens with undamped metal springs exhibiting a longitudinal mechanical energy conductance condition at frequencies higher than the suspension/plinth mass fundamental resonance.
Best wishes, Professor Bizzt
Pio1980
AK Member
A dazzling and thorough analysis, thank you for your insight.
Some off-the-cuff musings;
If this 'perfect' system from platter/spindle thru pickup/arm to plinth back to spindle is modeled as a parallelogram structure, the only points of 'give' is the elastomeric suspension of the stylus in a 'conventional' pick-up and perhaps the oil film of the spindle bearing assuming "hard sonic grounding" thru the arm bearings. If a pick-up with an axis pivot wire like an MC, Grado Fluxbridger, or A-T dual magnet, ect, is used there is an even more rigid structure. Going with something very unconventional like a DECCA 'London' "tip scanning" pick-up with no suspension 'give' or cantelever flex to speak of makes things very interesting indeed. Add the very firm grounding that a hard vacuum platter, in combination with a "perfect" LT arm, should give results as theoretically sonically 'rigid' as high-resolution digital recording and playback can afford (if the source material is up to standard) and the differences narrowed to near indistinguishably.
Some off-the-cuff musings;
If this 'perfect' system from platter/spindle thru pickup/arm to plinth back to spindle is modeled as a parallelogram structure, the only points of 'give' is the elastomeric suspension of the stylus in a 'conventional' pick-up and perhaps the oil film of the spindle bearing assuming "hard sonic grounding" thru the arm bearings. If a pick-up with an axis pivot wire like an MC, Grado Fluxbridger, or A-T dual magnet, ect, is used there is an even more rigid structure. Going with something very unconventional like a DECCA 'London' "tip scanning" pick-up with no suspension 'give' or cantelever flex to speak of makes things very interesting indeed. Add the very firm grounding that a hard vacuum platter, in combination with a "perfect" LT arm, should give results as theoretically sonically 'rigid' as high-resolution digital recording and playback can afford (if the source material is up to standard) and the differences narrowed to near indistinguishably.
Pick a Strain Gauge cartridge from Soundsmith for that ultimate system...
Descartridge
Stereos been berry, berry good to me!
Yes indeed, the strain gauge cartridge does sound very nice with the PL L1000. Mine was a rare offering on the bay, via a tip by Prof Bizzt.
Here is some more info about the PX-1 from a bloke who has one:
http://www.audiokarma.org/forums/showthread.php?t=129114
http://www.audiokarma.org/forums/showthread.php?t=129114
I already mentioned it in another PL-800 thread that putting a bit of teflon grease on the tube where V-shape tonearm rides dramatically improves the tracking. The "jerkiness" is no longer visible. No skipping either. Especially after 5-10min warm-up when the tube gets warm.
vbmagus1980
Member
Regarding the PX-1, i did see one in Akihabara last year while i was there. What that pic is missing is the huge power supply that comes with it. In the same store was also the ELP Laser Turntable which i have always wanted to use (and own hehe) but the PX-1 is quite a sight! An absolute monster of a TT. But i do have a PX-2 which has been in storage for over 2 years as the photo interrupters were shot but the Professor has just replaced them for me just recently. So once the Sensor Board is back in my possession, and my PX-2 is 100% Operational, you can be sure ill be making happy posts 
Strain gauge cartridges
Hello Pio1980,
I'm not quite sure I understand what you mean by eliminating the phono pre for a direct drive etc.
In short, a strain gauge phono cartridge is an electromechanical transducer that operates by having its two electrically resistive elements mechanically modulated by the record groove. This creates a varying resistance in the two strain gauge elements.
A strain gauge cartridge requires a small precision external constant current source that in conjunction with the record groove modulated resistance changes, creates a signal mirroring that encoded in the groove.
From what I know (and what do I know?) these cartridges do not typically require much inverse RIAA EQ or other EQ to have flat frequency response. There are many reasons they work so well, but that takes me off topic.
In closing, any patient person should be able to find a mid seventies Panasonic EPC-450C II, EPC-451C, or EPC-460 strain gauge cartridge and use it with a Panasonic SE-405 or Technics SH-400 strain gauge preamp and enjoy a decent introduction to strain gauge cartridges.
Remember the EPC-451C was good enough for John Iverson, Jeff Rowland, and I think a few others once upon a time. And if the EPC-451C was good enough for them, then it should be good enough for us. I know it's good enough for me.
Best wishes, Professor Bizzt
Hello Pio1980,
I'm not quite sure I understand what you mean by eliminating the phono pre for a direct drive etc.
In short, a strain gauge phono cartridge is an electromechanical transducer that operates by having its two electrically resistive elements mechanically modulated by the record groove. This creates a varying resistance in the two strain gauge elements.
A strain gauge cartridge requires a small precision external constant current source that in conjunction with the record groove modulated resistance changes, creates a signal mirroring that encoded in the groove.
From what I know (and what do I know?) these cartridges do not typically require much inverse RIAA EQ or other EQ to have flat frequency response. There are many reasons they work so well, but that takes me off topic.
In closing, any patient person should be able to find a mid seventies Panasonic EPC-450C II, EPC-451C, or EPC-460 strain gauge cartridge and use it with a Panasonic SE-405 or Technics SH-400 strain gauge preamp and enjoy a decent introduction to strain gauge cartridges.
Remember the EPC-451C was good enough for John Iverson, Jeff Rowland, and I think a few others once upon a time. And if the EPC-451C was good enough for them, then it should be good enough for us. I know it's good enough for me.
Best wishes, Professor Bizzt
Reducing the stress of life with strain gauges
Hello there ole buddy,
Wait till you hear the Panasonic EPC-451C with an excellent strain gauge preamp.
Best wishes, Professor Bizzt
Hello there ole buddy,
Wait till you hear the Panasonic EPC-451C with an excellent strain gauge preamp.
Best wishes, Professor Bizzt
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