[lcrim]

John:
I have the KAB outboard power supply and initially it was plugged to the balanced power transformer but I couldn't hear any difference when it went directly to the wall duplex and so it stays direct to the wall.  Francisco (PA) told me to replace the cables that Kevin uses but I never did.  Francisco was always very insistant on clean power.

[TheChairGuy]

Thanks, Lar.  I might try some 'conditioning' as I am still experimenting with the VPI HW-19 and I should have an old DUAL Idler Drive coming (thanks to HurdyGurdyDave)...both of which are AC motors and would certainly seem to benefit from some mains conditioning.

I don't know if the cables on the KAB outboard power supply is removable, but if it is - do it.  No change in wiring was ever so beneficial as the change in the 'umbilical' between my (long sold) MSB DAC and outboard power supply.  It was waaaay more beneficial than any speaker, interconnect, or power cable change ever was (and a couple of those weren't shabby upgrades).

Brad a Revelation Audio Labs makes customs umbilicals for nearly everyone.....just tell him your termination composition and he whips up a length for under $200.00.  The 'cleaner' delivery really helped in every case I've heard of...lowered inductance likely than the stock wiring, certainly less crystal boundaries overall than if Kevin uses basic copper cabling in his, and good shielding from tip to point, too.

Beats me if either use of silver wiring or a cryo process has any value in the outcome  ....I can only attest to the benefit of what I had. The difference was again pretty large on my old Musical Surroundings phono pre and outboard power supply on another length I had Brad make up for me.

Mr. PA/Francisco may indeed have been right again 

John

[hurdy_gurdyman]

Thanks, Lar.  I might try some 'conditioning' as I am still experimenting with the VPI HW-19 and I should have an old DUAL Idler Drive coming (thanks to HurdyGurdyDave)...both of which are AC motors and would certainly seem to benefit from some mains conditioning.

I'm interested in this, seeing as both the Dual and my ROK have AC induction type motors. I'd think they would benefit from both conditioning and voltage regulation. These motors are somewhat susceptible to voltage variations. It would be great to have a device that would hold constant voltage as well as clean voltage.

Dave

[WGH]

Here are the technical service manuals and an excellent scan of the circuit diagram for the Technics tables.

Technics SL-1200 / 1210
Technics SL-1200LTD
Technics SL-1200 Circuit Diagram

[Wayner]

I got off work early today and started doing some measurements on the SL-1200. 2 things still bother me. One is the anti-skating is off by .8. In otherwords, my cartridge is dialed in at 1.5 grams exactly, but to get zero inward or outward tonearm drift (using my blank disc) the skating setting has to be set at 2.3.

The other thing is the now popular VTA setting. That is off by 1.55mm (lower). The specification for the AT440MLa states height from top of mounting plate to stylus is approx. 17.3mm, which should be a 2.3 setting on the SL-1200. It ain't. Back of the arm is too damn high. So I dropped the dial to .75 and with a height gauge, confirmed a very parallel arm tube to record surface with stylus on the vinyl. However, the headshell with it top has a optical illusion with the top surface being tapered, making the cartridge look like it's going down hill. Measuring the mounting surface of the headshell to record surface front and back suggests a slight error. In conclusion, I believe there are some tolerance build-ups in the arm from headshell to arm tube to pivot assembly. It's a BITCH to get all this to come together, but in the final outcome, it is the cartridge top surface that must be parallel to the record surface, the tonearm could be as crooked as a stick as long as it puts the cart in the right spot. Also the ear is the final judge when it comes to VTA. I might go mad before this analysis is over.....

Wayner

[TheChairGuy]

I might go mad before this analysis is over.....
Wayner

Outstanding, Wayner - maybe we can get a two-fer in the Vinyl Wacko Ward together.  Sorry, but, we'll have to check in one here in San Fran...I'm never be whacked enough to live thru Minnesota winters 

John

[TheChairGuy]

I found out I was slightly off in my installation of the Orign Live armboard (washers I put under a part of the armboard instead of on top).  As Origin Live/Mark Baker goes to great lengths to couple and de-couple these armboards for best sonics, I thought it important I get it right.

So, I dissembled the Technics last night and re-installed the washers correctly.

I didn't notice one iota of difference in sound. It still sounds good...tho I keep thinking there is a little annoying stridency with all 3 cartridges I've used thus far.  Is it some geometry issue, something inherent in the Technics...or something else I'm not quite sure yet.

That's my contribution to the bastardization of my Technics today 

John

[Wayner]

I assume you are using the 8.468" stylus to pivot distance as the spacing from turntable spindle to tonearm pivot didn't change? Or, what spacing are you using, me wonders? My logic tells me that the spacing from the original SL-1200 tonearm should be used.

Wayner

[Wayner]

Decided to post photo of my height gauge.

Material list:

(1) 6" steel ruler, (1) 2" dia. mirror, and (1) wad of plasticlay.

I use it to sweep under the cartridge headshell mounting flange. I set the slideable stop so that there is just the minutest amount of gap and see if the gap stays uniform through the lenght of the mounting surface. This gets it really close for setting VTA.



W 

[TheChairGuy]

I assume you are using the 8.468" stylus to pivot distance as the spacing from turntable spindle to tonearm pivot didn't change? Or, what spacing are you using, me wonders? My logic tells me that the spacing from the original SL-1200 tonearm should be used.

Wayner

Mr. Geometry  ,

That is fortunately provided by the Origin Live armboard....precisely fit for all Rega, Origin Live and other Rega-clones or upgraded arms in the market.  I say fortunately for several reason...not the least of which is that I am a Marketing major, not math whiz 

John

[Wayner]

The hum level from my set-up is starting to bother me. One issue is the incredable gain in the phono stage of my Van Alstine T8. The T8 is cranking like a bastard at 9 o'clock volume position and if I have no source playing, I can hear hum when turned up to that level. What does that prove? That when I am not playing a record and turn the volume up...... well, you know. It is amazing that I can hook up my Empire to the T8 and there is almost no hum, even with the T8 at full volume, same with the VPI/Audioquest PT-6. The Rega has some, but the Technics wins the blue ribbon. The goofy thing is that I have hum with everything on the table off and even unplugged. So today I will play musical chairs by table swaping to see if the hum is coming from the amps and/or try some goofy shielding technics. Where the hell can I find galvanized steel on a Sunday..................

Wayner

[richidoo]

440+T8 is no problem as proven with your other TTs. So the loop must be between TT and cart. Probably signal ground is connected to TT chassis, PS or signal output jacks or somewhere inside the TT. If the TT has a 3 prong plug (my Q2 is 2 prong) then you can lift the safety ground with a cheater which might help, but not always. Try to float the signals' hot and ground all the way between T8 and cart. If the cart touches the arm you can use .001" thin kapton insulation sheet made for transistors.

What's the galvanized steel for? Grounding I suppose?  Home Depot has framing joist hangers which are galvanized steel. In that section there are flat pieces too, of varying sizes. But a length of 8ga copper wire would make a better ground buss, especially if you are gonna put signal ground on it too. Steel doesn't sound good.
Good luck!!!
Rich

[Wayner]

I think the problem is solved (for the most part). Using allegator clips on the cartridge leads, I shorted out the + and - of both sides (independantly) of the cartridge and turned the volume up. As I suspected, the noise is from the internal tonearm wiring of the SL-1200. However, I also had a location issue with the electronics (amp/preamp). By moving the table a little further away from the amp helped some, the real hum killer came when I used an allegator clip and tied the two commons together at the cartridge. that's funny since the commons of the cartridge end up connected together in the pre-amp anyway, I think the 2 ground wires paralleling thru the arm created an internal tonearm ground loop. Perhaps the Empire has better wiring or it is twisted internally, I don't know. Anyway, I ended up soldering a short piece of wire between the 2 ground clips. Hum is easily cut by 75% I would guess.

As for the steel or galvanized steel, If all else failed, I was going to make a Faraday shield. That needs to be made out of some form of steel and connected to earth ground. It is an effective EMF stopper if proximity can't be helped. I only thought about galvanized because I wouldn't have to paint it. Now, I don't think I need it at all. Sounds great right now......

Richidoo....you may have to do this to your SL-Q2 if you use the AT440MLa.

[Wayner]

One more discovery to mention here and I guess I do this to inform people if they plan on buying the SL-1200 of some of it's few weaknesses. Of course, back on the hum problem, I never bothered to sweep the tonearm across the record playing area with the volume at elevated levels for hum detection. Obviously, we're not playing a record, in fact the table isn't even turned on to do this test. I notice a slight amount of hum (with volume really cranked) with the arm sitting on it's perch. When I moved it across the mat, I thought the hum would get louder, since the cartridge was in closer proximity to the permenant magnet built into the platter. What actually happened amazed me at first. The hum all but dissappeared! I guess this makes sence, since the magnetic field is mostly in the horizontal plane. and which is why the little bit of hum is detected with the arm on the rest, because it is parked in the horizontal plane. The sloped edge of the platter offers less shielding than the area over the rest of the platter.

To summerize, the hum problem has been resolved and is a non-issue after connecting the negitive of the left and right cartridge leads together as described on an earlier post. The table is not as quite as the Empire 598, but I dout many tables could match that low hum level.

I certainly recommend this table to almost anyone, espically if this is your first. It is not plug and play, however. I feel if you come to understand some of the issues brought up here, your enjoyment will be extremely elevated. cartridge set-up and alignment, as with any table, is well worth the time invested. It also helps to understand geometry and be able to measure (and follow directions). The KAB modifications may be worth the investment. That you will have to decide for yourself. For $500, plus cartridge, I don't see how you could do better and not spend a couple of G's. That's my story and I'm stickin' with it. 

The tone arm is pretty good too.

Wayner  aa

[richidoo]

Thanks Wayner, great and thorough review! I'm gonna try that ground "bonding strap" (what we used to call the 0ga wire that connected two engines in a boat) to see if it improves hum on my Q2/ShureM97/Bellari.
Rich

[Jampot]

Be interesting to see what this fetches-

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=150202707288&ssPageName=STRK:MEWA:IT&ih=005

Not fitted with height adjustment which seems a bit remiss of the original builder...

Jim

[TheChairGuy]

So today I received two additional goodies I'm playing with...a frickin' georgeous Origin Live Illustrious Mk. III tonearm (wow , this arm is purdy) and a WIZ Isotap 'stepped' isolation transformer.

The arm will take some time to set up, but the isolation transformer is an immediate toy...just plug in and play. Even with a very exacting DC Servo motor, isolating the mains and regulating mains is beneficial.  You need not be a golden eared boy to hear the difference immediately.  The notes have a more exacting nature - it's wild - especially notable is the greater definition of the bass notes and strikes. 

I started at 115 volts and now have dropped to 90 volts.  Is it possible that reduced voltages to a DC motor can improve things further (techies and other knowledgeable folks please chime in)?  It's either a very subtle change for the better at 90 volts or I am making myself believe that it is    Which has happened more times than I want to remember.

My suspicion has been on this deck that it was over-loved in a former life and the motor is noisy and making it's way to the stylus.  It's not as well isolated from feedback and vibration as my JVC DD (stuffed with 9 lbs of Plast-i-Clay).  I think, brand new, these Technics 1200's should be pretty well isolated from feedback, but as I read on Kevin/KAB's site, they get noisy over the years.  So, I think mine will need to go to New Jersey for a $300 outboard motor and strobe disabler sometime in the future.

But the isolated transformer and reduced voltages seem to be taxing the motor less severely and it is playing more quietly...which translates to better tunes in here 

I think the Isolation Tranny will prove even more beneficial to the altogether unregulated AC Synchonous motor in the VPI when I get it over there.

John

[TheChairGuy]

The VIZ Isotap 'stepped' Isolation Transformer (RCA also made them).  Quite a handy device as it isolates and steps down voltages so motors run less stressed.  At the very least it regulates the voltage better than it may be streaming from your wall outlet.


Quite a little kick in the pants for $50 spent    It's reassuringly heavy....I'd estimate the mid-sized can weighs 10-12 lbs. It's also very quiet - I haven't listened intently for hum, but I cannot hear it within a few feet (with music off) of it and it is rather vibration free by touch.

[Wayner]

John,

Do you use a VOM to dial in the exact voltage, or just trust the front panel controls?

Wayner 

[TheChairGuy]

John,

Do you use a VOM to dial in the exact voltage, or just trust the front panel controls?

Wayner 

There is a (nicely framed) Bachelor of Science in Business Administration and Marketing from Villanova University on my wall.....I never stepped foot in the Engineering School for fear of contaminating it 

John