09-02-09: Hiho
T_bone, I do have an SP10mk2 that spins way too fast, something like 200 or 300 rpm. Is that something I can repair by replacing all the electrolytic caps? Or is that something related to the obsolete chips? Hiho, with my MK2 it was caps, with my MK3 it was a cap that killed an IC. The most common cap in a Technics MK2 causing speed error is the large vertically mounted electrolytic located directly behind the face plate of the outboard power supply. (Wish we could put images into these posts!) Here is a list of the stock values I replaced in my outboard power supply. There are more under the platter. #.....uF.......VDC (1) 100 .......16 (1) 100 .......16 (1) 1000......16 (1) 100 .......50 (1) 100 .......50 (1) 1000 .....80 (1) 22 .......160 (1) 100 .....160 The following are what replaced the list above. I purchased mine from Mike Percy #.....Brand............uF..........VDC (4) Nichicon ..... 100uf......50V ES (NP) (1) Nichicon .....1000uf......25V ES (NP) (1) Nichicon .....1000uf....100V FV (polar) (1) Black Gate ... 33uf....160V standard polar (1) Black Gate .....100uf....160V standard polar Hope this helps, I would check to be sure Technics did not change values from model to model before ordering. This should be a good start though. |
A Technics table gone rogue... |
Yep, that's how fast my faulty SP10 spins! I could have turned that into a lawn mower.
Albert, thanks for the cap info. I used a functional power supply that I know for sure works to connect to the broken SP10 and still had the same problem so I don't think it's a power supply issue. It's something in the SP10 boards.
However, I have two extra bad power supplies that I think I need to recap so your info will come in handy. I copied and pasted it for future reference. Thanks again!
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Hiho, It is quite possible that your speed "error" (if you want to call 200 rpm a mere error) is due to a leaky or deceased electrolytic. The best way to find that out is to replace the lytics with new ones. It really does not matter much what brand you use; all modern lytics will be an upgrade. Panasonic low voltage caps (FC type) are superb and cost a bit less than the ones Albert listed. I would start with the power supply. Disconnect it from the main chassis, turn it on, and measure the DC voltages at its outputs. (You'll need a manual, perhaps.) You should see 140VDC, 32VDC, and 5VDC with very little ripple (less than 1VAC, for example). If the voltages are only slightly off, and if there is acceptable ripple, then the supply is probably not to blame. There are pots inside the PS chassis with which you can re-adjust the DC outputs to conform to the expected values. OTOH, if voltages are way off or if there is significant AC voltage at the outputs, THEN you might change the caps first of all. If you have a cap meter, you can test each cap individually for leakage, or you can empirically change them all, because if they are not detectably bad now, they might soon be. There are only about 8 caps in there. If you can snag a service manual from Vinyl Engine or some other source, you can look up the parts list for the PS and simply order the ones you'll need. I bought my Panasonic caps from Digikey, I think, but there are other vendors, too. There is one high-voltage cap, maybe the 1000uF/80V in Albert's list. I actually used a 2000uF/200V Panasonic TS-ED type, because it exactly fits the clamp. It way outperforms the original. There's no harm in using a higher value in this position, but in other cases it's wise to use the same value in capacitance. The DC voltage rating can be the same as original or higher, but not lower. After you have checked out the PS, then turn your attention to the on-board electronics. This is a crapshoot, because it IS possible that one of the ICs has already blown, in which case you will be searching for it. I think Albert can help you there. |
Hiho, you say you have "a functional power supply" and "two extra bad supplies". Are these all SH-10E(A) original equipment units? Since they seem to be quite rare separate from the tables is why I ask.
If you have anything other than original power supplies, do they supply all three voltages that Lewm identified? |
I have three SP10mk2 units with five original power supplies, two are bad that needs to be repaired. I can take care of the power supplies and I do have a service manual. Since I have experience in building tube amps and judging by the schematic, it's not that complicated. However, I am certainly no expert when it comes to integrated circuits and chips! The one SP10 with speed issue is definitely in the boards inside the SP10 chassis. Yes, it's a crapshoot. An IC might be blown or it could be a bad cap. I will attempt to fix the extra power supplies first and then move on to the bad speed unit. Fingers crossed. It will take some time as I am in no hurry as I still have two other functional units. But I don't even use them that much because I am quite happy with my other turntables right now. Thank you so much for all the information posted here and I really appreciate the help, which makes this hobby worthwhile.
Happy listening and fixing stuff!
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Hi All,
I've got 2 mkii's and one chassis ala Albert Porter. I've replaced all the caps in my PS, but none on the table's boards. Relative to the PS, how critical are the caps on these boards? Also, how difficult/easy is it to access these boards, get them out of the chassis, and replace the caps? Finally, how many caps are there on the internal board(s)?
Another unrelated question... my second chassis is pretty darn ugly. If I wanted to give it a facelift, perhaps make it black, what method would you suggest, within the "reasonable cost" category.
Thanks, Peter S. |
I take the position that any modern electrolytic of recent manufacture (and of proper value and voltage) will be fine to use anywhere in the MkII. Ergo, I use Panasonic FC or TS-ED types, depending upon voltage needed. They are cheap and have vanishingly low ESR, compared to anything that was made back in the 70s and 80s. Others might tell you that they can "hear" the differences among electrolytics in this circuit and would therefore use boutique brands of caps. I don't choose to argue that point either way. IMO, the caps on board the main chassis are every bit as critical as the PS caps, and maybe moreso, since they reside in proximity to the ICs and transistors that function in the servo circuit. Getting at them to replace them looks to be not too bad. I am going to give it a try myself.
If I wanted to restore an SP10 cosmetically, I would have it done professionally by an experienced company. Such a one can be found in the UK; I don't know their web address. Google will find it, I think. Unfortunately, their service is not cheap. Fortunately, the workmanship looks excellent. |
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OK - so I'll go to Mouser and purchase the replacement caps for the boards. I did a quick count from the replacement parts list in the service manual and it looks like there are about 30 electolytic caps on the boards. One thing I just don't get: the specs for these caps are strange. I'm used to seeing capacitance followed by minimum voltage. Why does the service manual show a variety of units for the spec following the capacitance. I see a number of units, examples include: 50WV,50W, but no 50V. What gives???
Also, regarding restoring the deck - I don't think I'm so perfectionist to pay 500 pounds to restore the surface of the deck. I was thinking of something on the order of an auto body place - something where I could tape up everything except the top and side surfaces and have them do a nice job. I know it would be a departure from the original, but this is a second deck - and it wouldn't bother me, as long as it looks good! |
I think all those units really are for voltage.
Re the body shop approach, go for it; it belongs to you. I agree that 500GBP for a re-finish is way too high. That's why I was very fussy about cosmetics when I bought mine. It's quite possible you could find someone to do it well for less money than Vantage Audio. |
"Also, regarding restoring the deck - I don't think I'm so perfectionist to pay 500 pounds to restore the surface of the deck. I was thinking of something on the order of an auto body place - something where I could tape up everything except the top and side surfaces and have them do a nice job. I know it would be a departure from the original, but this is a second deck - and it wouldn't bother me, as long as it looks good! "
My first SP-10 mkII looked real bad. Scratched and oxidized. I stripped all the parts from the alu chassis and carefully sanded it down. Took it to an auto-body-shop and had it spray-painted in jet black 2K enamel. Looked ultra sleek. If you do it properly it will look great.
BTW - You did get the SP-10 mkII in matt black - they are just very rare. My friend has a black SP-10 mkII. I can send a photo if you like. |
Lonestarsouth, What did you do re the on/off button, when you had the chassis painted? Did you leave it in brushed chrome? That would look cool. |
"Lonestarsouth, What did you do re the on/off button, when you had the chassis painted? Did you leave it in brushed chrome? That would look cool."
Yes. I left it original. The Technics factory original black SP-10 mkII also had the button in aluminum finish. |
Peter_s:
You asked, "...how difficult/easy is it to access these boards, get them out of the chassis, and replace the caps?"
Assuming you're asking about a MkII, it's pretty easy, and the boards are old 70's technology, so they're very easy to work on without damaging them.
To get at the boards, you need to remove the bottom cover, which is held on by a bunch of small screws. The boards will then be exposed. There are 4 boards, 3 of which plug into the one in the center. There are 3 or 4 screws holding each board in place, and some brass standoffs. Remove the screws and standoffs, unplug any cables plugged into the board you want to remove, and the board just slides out of the edge connector.
The boards are all pretty rugged and use double-sided copper, so they're pretty hard to damage. Work on the "underside" of the board, i.e. the side opposite the one with the parts on it with a 25-35W iron. Personally, I just use one of those spring-loaded solder suckers and suck as much solder as possible off the pad, then finish the job with solder wick. The part(s) should pop out.
Watch the polarity of the electrolytic caps. Also, I recall that Technics used a "22V16" numbering system on their schematics, which means 22uf and 16V. Something like that.
John L. |
Thanks John,
I've tallied up all (23) of the electrolytic caps for the boards inside the table directly out of the service manual. My list is below. Again, I assume that the "WV" and "W" ratings are all meant to be volts. If I am wrong, someone please let me know before I order them!!! Also, I assume there are no concerns requiring replacing other caps, such as polyester, styrol, etc).
Thanks, Peter
ELECTROLYTIC CAPS FOR TECHNICS SP10-2 CIRCUIT BOARDS (23)
DRIVE CIRCUIT BOARD
C7,8,12,13,14,15,16,17 (8x) 1 uF 50WV
C20 (1x) 2.2 uF, 50WV
C2,4,6,18 (4x) 10 uF, 50WV
LOGIC CIRCUIT BOARD
C201 (1x) 1 pF, 50WV
C230 (1x) 2.2 uF, 50WV
C202, 218, 225 (3x) 10 uF, 16WV
C227 (1x) 100 uF, 16WV
C204 (1x) 330 uF, 10WV
CONTROL CIRCUIT BOARD
C106 (1x) 1 uF, 50W
C103 (1x) 100 uF, 50W
CONNECTIONAL BOARD
C301 (1x) 10uF, 50W |
Are you certain this is a list of electrolytic caps, or is it a list of ALL caps used of any type? For example, I find it hard to believe that they used a 1 pF (that's picofarad) electrolytic. That's a teeny tiny value. Even the 1uF caps are likely to be film types, or film types could be used there. 10uF and above are likely to be electrolytic types. Anyway, thanks for the list. I am about to suck it up and do the work on my Mk II, too. As for the units of "WV", perhaps it will be clearer when you look at the actual caps, which are usually labeled to indicate their voltage ratings. |
Isnt there a proper service manual for the SP-10 mkII on the web? |
I am not certain whether it is available as a "free" download, but you can buy it for a very reasonable sum at Soundfountain. Look in the SP10 section. The Owner's Manual of course can be downloaded at Vinyl Engine. |
Lewm, I am sure I can make a copy of my SP-10 mkII service manual. I got it with the machine in the box. |
Sorry, Lonestar, I thought you needed a copy yourself. I have one already that I bought from Soundfountain. (So it is not in e-format, only a hard copy. Soundfountain sends hard copies from Germany.) Thank you for your kind offer, however. |
There are indeed lots of 1uf 50V (same as "WV") electrolytics on the boards. Remember, this is 70's technology.
SP-10MkII and III service manuals are available for download on vinylengine.com.
John L |
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Re: number of electrolytic caps
The Service Manual for my SP-10 Mk2A identifies 24 'lytics in the main unit section and 8 in the power unit section. So, not much difference from Peter's count except he didn't include the power section which I've been told is most critical for 'lytic replacement. Of course the 2A replaced the multiple boards of the 2 with a single main board so removal should be easier.
Also, all caps are identified by a V, no WV or W.
Now, since I know so little about electronics, is there a consideration for replacing any of the diodes with new (faster) parts? |
The diodes are by and large Germanium types. No one uses those any more except in special applications. They have a low forward voltage drop, compared to some other even more modern types, so probably they should not be "updated" indiscriminately. Schottky diodes, the latest craze, have a low forward voltage drop too, and in one case I know the Germanium types in the PS can be replaced with Schottky's. Bill Thalmann, the guy who serviced my 2A and Albert's tables too, used some Fairchild Stealth diodes here and there. Problem is I don't know where. The only advantage of messing with diodes is possibly lower noise, which is all it takes to make us audio-dudes drool with desire. Bill advised me as a general rule not to worry about it, using the "if it ain't broke don't fix it" approach. You could go crazy and start replacing film caps, if there are any. No real reason to do it.
Has anyone tried any of the various after-market outboard PSs available for the MkII? I know there is one sold via eBay and one sold by Vantage Audio (for much bigger bucks). The VA unit looks really nice, with separate transformers for each PS voltage output, darnit. I could build one but it ain't gonna happen in this lifetime. |
One substitution you could consider for all those 1 uf 50 volt electrolytics are the Panasonic V series stacked metallized film caps sold by Digi-Key (part no. P4675-ND). These are very compact, low dissipation factor, non-inductive construction, and probably last much longer than any electrolytics. |
RE: How about the 1pF electrolytic capacitor?
Just for the sake of others reading this message in the future....
The "1pF 50V" electrolytic capacitor listed in the SP10 MarkII Service Manual (for the Logic Circuit Board) is clearly a typo and SHOULD be listed as a "1uF 50V" electrolytic.
Like Lewm, I was equally confused when I noticed a 1pF electrolytic in the parts list.
The Part No. in the Service Manual (ECEA50V1) is correct, however, and identifies the correct value (1uF).
Chris |
I just re-capped an entire MkII. You are correct. There is no 1pF cap anywhere, but then again I/we have found a few other errors in the Service Manual, most notably in the regulator circuit for the 5V supply in the PS module. One of the transistors is incorrectly designated as PNP type when it should be NPN (or vice-versa?), which caused me to have to give my PS to Bill Thalmann (super tech in Springfield, VA), who found the error quickly and easily. In point of fact, I doubt that a 1 pF cap exists; it is too tiny in value to manufacture with any degree of tolerance and moreover it is too small in value to make much difference. You get much more capacitance by just twisting wires. That's why I doubted its existence in the first place. There sure were a lot of those 1uF/50V caps, however, in the onboard electronic modules. |
DId you replace all the caps or just the electrolytics?
Did you substitute film caps for the 1uF electrolytics (as suggested by Jlin)? I've given this thought but wondered if the (larger) film caps would fit in the same footprint.
Chris
p.s. I've ordered a complete set of electrolytics and will do as you've done as soon as they arrive in the mail. |
I did not bother with the film caps, as per the opinion of Bill Thalmann, who says they tend to last indefinitely unless they are subject to excessive voltage beyond their rating. Also, I refuse to believe that one could "hear" the difference between the stock film caps and boutique audiophile caps, in the context of the tt electronics. One would be better off upgrading the diodes with lower noise parts. |
Hi, for those using wooden plinths, what footers seem to work with the SP10 mkll? Stillpoints, Herbies, Mapleshade to name a few, I would like feedback to form a starting point.
thanks |
Anyone know what are the specifications on the brass rod one would use to drain the vibrations from the SP-10's spindle? Also, how much torque?
Thanks,
Cr |
What a good thread this is! Thank you.
There has been a lot of questioning re. lengthening the cables so as to take the boards outside the plinth. My SP-10 arrived with me with the electronics in an external case connected by about 24" of multicore OCC connected with a normal computer multiway D plug to the electronics. The motor end is connected (soldered) to a tag board attached to the motor.
I can assure you that this modification gives for a far quieter background than when the TT is as standard. Other than replacement of electrolic caps and a few other passive component the electronics are totally standard. I was using for several years a B7 solid obsidian plinth and a 'Plexiglass' armboard which I replaced with a 1" finest grain solid carbon board - Carbon NOT carbon graphite bon. (Arms used include FR 64S (best) Graham (does not suit my very low compliance heavy MCs) and Zeta which is pretty good.
If I could find a big block of solid fine grain carbon here in the UK at a sensible cost I would have the whole plinth made of the stuff...as it is I am now going to use natural slate. |
Rnadelman, Choosing feet is like choosing a way to comb your hair. Everyone has a different idea of what is best. I recently purchased some of those huge feet that TT Weights make for their own Christine turntable. The feet are for sale here on Audiogon. I have not yet had a chance to audition them, but they provide no "suspension" effect, per se. I had a special need for feet at least 2 inches in height so as to clear the lead or iron block I use to drain vibration from the bearing. (Bought it from Albert Porter, so don't know whether it is lead or iron.) Other good feet for heavy tts include cerapucs, symposium roller block, etc., all of which are costly. You might find a used set here on Agon.
Impulse, The only place you might ever see that big a piece of pure carbon would be in a pencil factory (kidding). Can you post some photos of your SP10 with external electronics. Also, can you say how you know that outboarding the electronics results in a "far quieter" background. Have you heard it both ways? Thanks. |
Cknicker, I see now after all these months that I misunderstood your question of 11-07-09. You asked whether I replaced the 1uF electrolytics with 1uF film caps. The short answer is "no". The new Panasonic lytics in 1uF look to be very high quality stuff. On 11-08, I originally responded to your question in the belief that you were simply asking whether I had changed out the film caps per se. Did not do that either.
Impulse, Forgot also to say that just yesterday I read a thread on the French Lenco site suggesting that Panzerholz may be a better plinth material than slate, not that I am about to ditch all my slate plinths. Anyway, on that thread we have a materials science guy who has measured energy dissipation, resonance and damping factor of a number of different plinth materials. Nice data, but we have no way to know he is measuring the "right thing". |
Thanks for the clarification.
I replaced all the electrolytics with panasonics a while ago.
I'm about to mount my sp10 motor in a slate plinth Kaneta style (without the aluminum base). I'm looking forward to hearing the results.
Chris |
Hi Lewm,
Recently, I had the good fortune of listening to a Technics SP10 MkII table, a Technics SP10 MkIII table and a Garrard 301table in my system. All three of these tables were modified by Steve Dobbins of Xact Audio. The plinth for each table was made by Steve and each plinth used a different combination of materials to compensate for the different resonant characteristics of each tables motor. The two Technics tables are direct-drive tables and the Garrard table is a rim-drive table.
After listening to the Garrard 301 at my friends place, Steve Kaufman, I was very impressed with the sound. I have listened to Garrard 301s before. I thought that they had excellent drive but I thought they sounded dry, not much in the way of tonal quality.
The Garrard 301 built by Steve Dobbins did not sound dry at all. Rather, it sounded lush with beautiful detail while maintaining the drive characteristic of most 301s. I talked with Steve Dobbins about why his 301 sounded so good. He said it was a combination of many things but he said in addition to working on the plinth, motor and bearing, he designed a completely new platter. The new platter used three different materials none of which was aluminum. After talking more with Steve Dobbins about the 301, he recommended that I listen to his modified Technics SP10 MkII.
Steve kindly suggested that we listen to the MkII and the 301 in my system. Steve Dobbins lives in Boise Idaho and I live in Fort Collins Colorado. At Steve Dobbins expense, he shipped the MkII to my place and Steve Kaufman kindly brought over his 301 for comparison (Steve K. lives in Fort Collins). Steve Dobbins flew from Boise to Fort Collins to compare the tables. On a Sunday, Steve Dobbins, Steve Kaufman, Grant Gassman (a friend of mine and an audio nut) and I got together to listen to these tables.
To make this table comparison as fair as we possibly could, we used two Schroder reference arms with the same type of wood (jacaranda), both 12 inches in length and cryoed Nordost wiring. Steve D. moved my Soundsmith strain-gauge cartridge from arm to arm to keep the comparison as fair as possible. Steve D. carefully aligned the Soundsmith strain-gauge cartridge each time he moved the cartridge from one arm to another arm. The rest of the audio system was the same.
For reference, my audio system includes an Intact custom-designed strain-gauge phono preamp using a 437A WE triode tube, an Intact custom-designed auto-former volume control, an all DHT amp and a tri-amped speaker system. The DHT amp includes a Telefunken RS241 DHT tube and an Eimac 75TL DHT tube. Most of the iron in the DHT amp was designed and made at Intact audio. The DHT amp drives a field-coil driver designed at Emia by Dave Slagle. The field-coil driver is connected to a Lowther cone and basket. The basket is mounted to a 36 Azura fiber-glass horn designed and built by Martin Seddon. The DHT amp also drives a Fane horn-loaded tweeter. I use two Nuforce amps to drive Klipschorn bass horn units. The bass units are crossed over using a Marchand electronic crossover. Finally, I have a Hsu Research amp with its own crossover driving a Bruce Edgar refrigerator horn sub.
Ok, finally the comparison. We listened to the MkII first and I have to say I was disappointed. It had the usual great drive and rhythm but the tonal quality was dry. It didnt have the nuance that I like. Next we listened to the 301. I thought it was much better than the MKII, great drive and pitch stability along with the lush sound I heard at Steve Kaufmans place. Steve D. said he though I might not be happy with the MkII so he also shipped a MkIII to my place as well. So he set up the MKIII. Remember Steve D. shipped two tables to me and did all the hard work of setting up the cartridge on the arms. After getting the MkIII set up, we listened. It wasnt even close. The MkIII was in another league as Steve Kaufman said (Steve K bought the MkIII we listened to on the spot even though he had just had received the 301, hes using the 301 for his mono setup now). The rest of us though the same thing. The MkIII was substantially better than the 301 and previous to listening to the MkIII, I thought the 301 would be hard to beat. The MkIII and the MkII were worlds apart. The MkIII made the MkII sound ragged by comparison. The MkIII had it all, wonderful nuance and space while retaining the great drive that direct-drive turntables are known for. All four of us have the same opinion. I believe anyone interested in good sound would have heard the same things we did.
Last week, I sent a check to Steve D. for the MkIII he recently build and delivered to me.
John P. |
Hi John P.,
Sounds like a well-controlled experiment and awesome good time! Congrats on the MKIII sourced from Steve...I guess I know where to go for a MKIII :-)
Best,
Sam |
John P,
Thanks for a well-written description of the comparison. Can you tell what you (or others) think is responsible for the difference between the SP-10MkIII's substantially better sound when compared with the modified SP-10MkII?
Was the Mk3 modified as well? What was modified? Were the plinths the same or somewhat/substantially different? |
T-bone,
The MkIII was modified as well by Steve Dobbins. The plinths for each table used different materials to deal with the motor noise created by each table. Steve Dobbins described to me what he did with each of the three tables but I don't remember them all. Maybe Steve D. could weigh in here or maybe you could contact him directly for the information. The work he did on all of the tables was substantial.
John P. |
Dear Johnp,
First of all, thank you so much for taking the time and energy to type out your report and post it here. It seems you took great pains to get valid data relevant to a comparison of these great turntables. But I must confess, there is so much information in your post that one essential element eludes me; were the MkII and the Mk III BOTH mounted in Steve Dobbins' plinths? Also, what platter mats did you use on the Technics tables? One conclusion that I have come to is that the stock rubber mats, supplied with the Technics tables and with my Denon DP80, and with most of the classic vintage Japanese tt's, are suboptimal at best. I found that an SAEC SS-300 metal mat makes both the DP80 and the Mk2A sound much better.
Also, in some respects your report is at odds with what others have told me, mostly in private, which is that the Mk III is better than the Mk II, as one might expect, but that the differences are subtle and of degree rather than of quality. For example, the Mk III was said by one person to have better bass reproduction, period. Another user who owned both tables told me not to bother with a MkIII if I have a MkII, because the upgrade was so subtle. I have also read and heard that the Mk II had a "dry" sound, as you suggest, but I never read a similar comment about a Garrard 301, with or without Steve's platter. The 301 is generally said to sound full and lush, as you say of your Dobbins-modified version. In an unsophisticated solid slate plinth and using the SS300 mat, my Mk2A definitely does not sound dry, but I can tell where that criticism comes from based on previous listening to a totally stock SL1000. None of this is to say that you are "wrong" in any way. It's just to point out how we each may experience the same thing in a different way. The fact that your panel of listeners reached a consensus is very convincing and makes me think my own judgements may be in error or that this is also dependent upon downstream components. Anyway, I now own a Mk III, so I will soon be able to listen for myself. (BTW, if anyone knows how to access the bearing of a Mk III so as to check and replenish the lubricant, please let me know here or in private.) |
Johnp,
great report on the shootout between the Dobbins tt's.
as i own(d) all three of those exact tt's (i sold the Mk2 last year and still have the Mk3 and 301) your report has interest to me.
first a comment; i never percieved my Mk2 with Schroeder Ref SQ arm as 'dry'. audiophile terms are not exact things and one man's dry is another man's 'detailed and transparent'....in any case, the Dobbins Technics SP-10 Mk2 was involving and natural sounding to me. OTOH i've not had a Strain Guage cartridge in my system.
a question; did the Dobbins Garrard 301 use the Loricraft UPS 301 AR power supply? i've only heard mine thru my Loricraft so i'm just wondering about how the presence or not of it might affect things. |
one more thing......thanks for the report on the Dobbins 301 platter. Steve is supposed to be visiting me in a few weeks and he'll be bringing the 301 platter which i'm planning on purchasing. |
Hi Lew,
"But I must confess, there is so much information in your post that one essential element eludes me; were the MkII and the Mk III BOTH mounted in Steve Dobbins' plinths?"
Yes, both were mounted in Steve Dobbins' plinths. However, all three plinths used different materials and construction. Each was designed to reduce noise transfer from the particular motor of each to the armboard and platter of each. Steve tried many combinations.
"Also, what platter mats did you use on the Technics tables?"
The MkIII had a SAEC SS-300 with a sorbathane "like" material on top of it. The MKII had the orignal rubber mat. Since getting my MkIII, I have tried two different mat combinations. First I compared the original rubber mat to a Saec SS-300 with a Herbie's Way Excellent Mat on top of the Saec. The Saec & Herbie combination sounded muffled and dull in comparison to the rubber mat. Next, I compared the rubber mat to the Saec mat alone. I couldn't hear any difference between these two mats. For each of these comparisons, I adjusted the VTA on my arm to get the best sound for each combination.
The 301's I heard previous to listening to Steve's 301 were uninvolving for me, no "juice". The plinths were different so maybe that would account for what I heard, I don't know for sure.
I don't remember all the modifications that Steve did to these three tables, but I know what I heard. In this situation, the MkIII was much better than the MkII but maybe in a situation with different plinths with different modificaitons the outcome may be different. I can only give you the conditions for this comparison and my opinion, for what it's worth, given these conditions.
Best,
John
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Hi Mike,
I not sure what power supply Steve used during the shootout.
Best,
John |
John,
You wrote, "The MkIII had a SAEC SS-300 with a sorbathane "like" material on top of it. The MKII had the orignal rubber mat." Perhaps that had something to do with the across the board superiority of the Mk3. But with quasi-sorbothane on top of SAEC, it would seem that the "sorbothane" would dominate the sound picture, as compared to the SAEC.
But then you wrote, "Next, I compared the rubber mat to the Saec mat alone. I couldn't hear any difference between these two mats." Wow! They sound quite different in my system. The SAEC seems to impart a lower noise floor compared to the stock factory mats on either the Denon DP80 or the Technics Mk2A; on both, I can hear inner detail better in all frequency ranges with the SAEC vs rubber.
I am not touting the SAEC in any way over all other possible substitutes, because it is the only one I have tried. I am curious to try others. Clearly, the mat makes a big difference. However, with the direct-drive tables one must be cautious about using a (metal) mat that is very much heavier (or very much lighter) than stock, for fear of upsetting the operation of the servo mechanism that maintains stable speed. That's how I glommed on to the SAEC. It is less than twice as heavy as the stock rubber mat. |
Hi Lew,
Steve Dobbins was suprised when I told him that I thought the SAEC and Herbie combination wasn't as good as the rubber mat. I think he was also surprised that I though the SAEC alone sounded about the same as the rubber mat. Steve Kaufman has a carbon mat on top of the SEAC mat and really enjoys it, so it looks like there isn't really agreement on mats. I'm not sure why.
John |
Lew, not to muddy the waters but I believe there was more than one mat for the Technics. My Mk2A has the matching mat as the parts list, SFTG172-01. I saw another on a Mk2 that had more circular ribs and seemed to be lighter/less hard. I don't know if that was stock or not.
Also, does anyone have a stock Mk3 mat to compare part numbers against the one above?
I also have an AT-666 stabilizer (metal) mat that Raul recommended. I'm long overdue in trying it due to continued delays with a proper plinth for my Mk2A. Hopefully not much longer now. |
Pryso, I had both a MkII and a Mk2A for a while. You are quite correct; there is a difference between the rubber mats supplied for those two tts. The MkII mat has those fine concentric rings, as you say, and may be more flexible, made of less rigid or thinner rubber, compared to the 2A mat. The Mk2A mat resembles, if it is not identical to, the rubber mat supplied with the Mk3. (I also have the correct original mat for my Mk3; it is not warped, but I expect to be using something more like the SAEC, based on my listening tests with the Mk2A and DP80.) Problem is also that my Mk2A mat is NOS, was never used and therefore warped a bit during storage. There must be a way to flatten it, but that is what motivated me to shell out money for the SAEC mat, which came highly recommended by Raul.
John, This business of piling one mat upon another seems a bit odd to me, unless it is to build up the mass to match that of the stock rubber mat, which is a good idea. I really like the Boston Audio Mat 1 on my Lenco, but it is way too light to use by itself on a Technics, due to possible effects on the servo. |
Lew, wild guess here. On Vinyl Asylum there has been some discussion of boiling rubber tt belts to restore original tension, apparently as recommended by VPI. I'm wondering if you could boil your warped mat in an appropriately sized pan to see if the rubber "remembers" its original shape? You might begin with three minutes in boiling water, then try longer times in one minute increments to see if that does not fully do the job. I can't see how this would hurt your situation and it might help.
Good luck. |
