Tuesday, February 4, 2014

Spinning Vinyl Again

I've been spinning vinyl again, and loving it.  The sound is pretty much the best I've ever had, with minor issue that will be explained below.

My vinyl spinner is a straight line tracking direct drive table from Japan in 1980, a Mitsubishi LT-30.  My first unit worked fine out of the box, even though the ebay seller had not bothered to remove the platter or secure the linear tracking arm with the factory shipping plates.  The arm makes a very soft tick or bump sound just before it moves while tracking the record.  I have a recollection of a straight line tracking table in the 1980's doing exactly the same thing, and I think it was a Mitsubishi, and the reason I did not buy it, even though way back then I didn't really think it was such a big deal.

Anyway, I spent a week after unpacking the first LT-30 not actually playing music through it, just testing how well it tracked records, and adjusting the user accessible adjustments.  I wanted to be sure it was OK before mounting my Dynavector Karat 17D2.

In fact, the last weekend in January, when I received the first LT-30 on Saturday, was very busy and productive.  As usual, I hosted a discussion and movie party on Sunday from 3-9 PM.  I spent most of Saturday preparing for that by cleaning up the living room, which was filled with stuff I had been working on (including the Sony PS-X800 turntable I had attempted to fix).  I needed to install the new set of UPS batteries in the Pure Audio UPS, move the UPS back into position, and set up the stack of components that rests on top of it (which had been strewn about the living room).  That included exchanging the Acurus A250 tweeter amp (which has waaaaay too much power for my Elac ribbon tweeters) with a Parasound HCA-1000A (which has less power, higher bias, circuit design done by John Curl and approved by my friend Tim as being the best possible, and is direct coupled).  I wanted to set up the Parasound also, but I found out that it wasn't working.  Then I found the problem, a blown line fuse, and recalled the experimentation with the PS Audio Power Plant Premier when I had an APC Smart UPS 1500A on the same multi room AC circuit.  The two power conditioners on the same circuit were fighting each other, my equipment was buzzing, especially the Parasound amp, then the fuse blew.  I don't think there was actually a problem with the amplifier.  Anyway, it turns out the Parasound uses a 3/4 inch line fuse, and all my line fuses were 1+ inches.  After putting more than an hour into the effort of getting the Parasound running again, I simply abandoned that project, but put the Parasound in the new equipment stack anyway, with the old Acurus taken out to my climate controlled storage building called Lyndhurst, where I had also gone to retrieve the Parasound.

With all that, and the party preparation, it was a wonder I even got the turntable unpacked, but I did, and started the testing and setup process.  I was actually spinning vinyl before the end of January, as I had promised a friend at the River City Audio Society meeting, but wasn't actually playing music from it until the following weekend.

I tried to get some answers on the arm ticking/bumping sound from a thread at AudioKarma during the week, but no answers yet.

Then the following weekend I finally got vinyl spinning AND sound playing.  Though it started with another busy Saturday.  I went to computer club meeting and gave a Kurzweil demonstration.  Then I had dinner.  Then I went to the San Antonio Symphony to see and hear a semi-staged production of Rusalka.  Then I went to the supermarket and did the shopping I had been postponing all week.

Finally I got to the actual vinyl playing setup on Sunday.  The first step was getting AC power to the related components (turntable, DB-8HG phono module, and Acurus L-10 preamp).  I though about various temporary solutions, but then jumped right in to what I wanted to do, taking a chance it would work, and it did.  I cut a hole in the back of my drawer/shelf chest, in one of the shelves.  That hole would allow me to put an AC power strip on that shelf, and run all the cords to and from it.  I was initially thinking I'd need a saw, and that would create a huge mess, and I'd have to move all the equipment (lots of it) off of the chest so I could move the chest out from the wall to vacuum up all the saw dust.

Fortunately, it turned out that the back panel of the chest is basically just cardboard, and it cut fairly easily with a utility knife.  I did take all the electronic equipment off of the chest anyway, to vacuum it off, and set it back with even more equipment on top.  But I didn't have to mess with the turntable or the piece of slate beneath it.  (Actually, I had already done this equipment vacuuming and setup BEFORE I was faced with this problem of cutting a hole or not.  So I REALLY did not want to move the equipment off AGAIN.)

Then the next problem was getting power to the power strip.  The hole I cut was not large enough to squeeze the power strip through, and just pushing the cord out from the hole I couldn't get it to go anywhere where it could be pulled out and attached to another cord to be connected to the main equipment strip.

The solution to that problem was cutting a short piece of string, and then attaching a metal object (actually, a cat nail clipper) to the string, and lowering it down from the top of the cabinet, I could then pull the string through the hole.  Then I could tie the string to the power cord of the outlet strip, and pull it back to the top of the cabinet, where I could attach it to another cord (I found the perfect 8 foot 14g cord in my cord box) to reach the sub-strip next to the TV.  THAT second strip connects to the main Monster Power strip that powers all my AV equipment, and that main strip is connected to my 20A dedicated AC line.

It also turned out to be easy to get all the equipment cords run through that hole just by lowering them from the top of the chest.  The plugs almost seemed to magically appear in the opening, and I pulled them in one at a time.  I connected the three things I needed to run right away, plus the three others I will be using in the future: the SAE impulse suppressor (a friend insists I use this when I copy his out-of-print records to digital for him), the Alesis Masterlink recorder (which I use to records LP's and cassette tapes), and the Nakamichi RX-505 cassette deck (which I can use to play cassettes I'd like to copy to digital, or just play cassettes).  So the metal outlet strip is nearly full now.

Once I got everything hooked up to AC power, I had to connect the interconnects.  I didn't use anything too fancy, but I did have a 1.5 foot length of premium OFC interconnects I got at CES in 1989 to connect the DB-8HG phono stage to the Acurus L-10 preamp, which then drives a pair of cables the 25 foot distance to my level-boost preamp, an Aragon 28k, which then drives my MSB PAD-1 analog to digital converter, which feeds AES/EBU to my system Tact preamp.

(And despite all that, despite all the long cables and multiple in-line buffers, all my care in AC connection and cabling shows itself as zero noise and zero buzz when listening to phonograph records).

I first played the Peter Sprague album I had been using for testing and setup purposes (because I considered it expendable).  Actually, this turned out to be a marvelous record, and all my messing around with it (even using the *gasp* cheap phono cartridge which came with the table) didn't seem to have hurt it at all.  Then I tried some Emerson Lake and Palmer.  First, Pictures at an Exhibition, then Tarkus.  I liked the Peter Sprague better.

The weekend ended well.  I texted my friend and she wanted to hear over the cell phone but I was hydrating in the kitchen and missed her call.  While I was hydrating in the kitchen, I used Sonos to pipe the sound from the bedroom turntable into the living room.  The Sonos system in the bedroom takes as input the tape outputs of the Aragon 28K used to amplify all analog sources to suitably high level for the MSB PAD-1 digitizer.  But the tape outputs are at just the right level for Sonos as they are not amplified to that high level.

Actually, before I even started on this project in earnest, something else happened.  I won my ebay auction bit on a Technics SL 1000 system, include SP 10 Mk2A turntable, Obsidian base, and EPA-100 arm.  That is the turntable I hope to use in my living room, with the Lenco L75 as an alternate (for testing or backup).  Since winning that bid, since before winning the bid actually, I've been talking with the seller about the details of packaging.  I had already ordered a shipping plate for the Technics motor on the expectation of winning this table, which has been a dream table for me for decades.

I never believed that direct drive tables, the better ones, are lousy sounding.  My previous favorite table, the Sony PS-X800 is a nice direct drive with wonderful sound.  Likewise my new LT-30.  When I mentioned my belief to an audiophile friend years ago he quipped "so where is your SP 10?".  Well I didn't have an SP 10, and I'd be the first to concede it could be an even better sounding motor than the one in the PS-X800.  So now I will have one, with a fine arm also, and I even believe the Obsidian base has been unfairly maligned--it would take considerable effort to make a better plinth, and the Obsidian can likely be made better without starting over (I hope) mainly by adding bottom decoupling (i.e. damping feet).  Anyway, the motor is superb and the plinth with dustcover will be very convenient until I get another one.  There is no reason to believe the Obsidian base is inferior to the base of the LT-30 or the PS-X800, in fact it's likely to be better than those, with the only weakness being the lack of damping feet.

So I've been very excited about winning my "dream" table.  Meanwhile, I just barely managed to check out the second LT-30 I bought for backup, parts, and experimentation during this weekend.  It was actually Monday afternoon by the time I quickly unboxed it and plugged it in.  And I discovered quickly the turntable didn't even turn on when I flipped the on switch (at the arm holder).  Later on Monday I opened an eBay "case" and sent a message to the seller about the claimed-to-be-working turntable.  But Monday night I took the bottom off the unit, and quickly discovered the problem.  The actual power switch was loose and was not getting enough push from the cam that was supposed to be pushing it.  I tightened the switch, and the turntable worked.  I put a record on it for testing (this time, I chose the Emerson Lake and Palmer Tarkus, my least favorite of the 3 records I played Sunday night) and it worked perfectly.  Despite the arm base seeming even looser than on the other LT-30, and despite the table generally seeming in slightly poorer condition, the arm does not make the ticking/bumping sound that the one in the bedroom does.

Anyway, I'm glad I had the opportunity to take a look at the bottom of the LT-30.  It is far simpler than the PS-X800 and looks like it can be much more easily serviced and experimented with.  I should be able to figure out how to fix that bumping sound.

But I've not heard any ill effect from the arm movement on my speakers.  What did strike me as being slightly wrong were the loud pipe organ bass notes from the Reference Recording of Respighi's Church Windows.  Right now I don't know whether the lumpy bass was caused by the arm/cartridge mismatch (I think the Dynavector 17D2 cartridge needs much more effective mass than the current arm and headshell provide) or by acoustical feedback.  It will be important to find out.  I can fix the effective mass problem by using a heavier headshell, like one of the Sumiko headshells I must have somewhere. I loved those Sumiko headshells, but I was forced to use a lighter headshell in the PS-X800 because it's auto-balance system didn't seem to be able to balance correctly with the Sumiko headshells anymore.

If the problem is acoustical feedback, I'm not sure it can be as easily fixed.  The table sits on a 50 pound piece of slate on the chest.  The chest is very strong vertically but can be made to twist horizontally by a millimeter or two.  If there is an acoustical feedback issue, it is most likely from this horizontal twisting.

It had been sometime during last week that I decided to go for my "dream" SP 10 turntable.  I had been looking at SP 10's and Denons on eBay and in discussion forums for the past month.  Finally, it was the sense that I really need to follow my bliss that got me going.  I'm a serious audiophile, and I take turntables pretty seriously, I think that rotational speed is very important, and I think direct drive is basically the way to go for best performance.  So why did I not have an SP 10 already?

But actually, I've had a number of conflicting feelings.  Not that belt drive is superior, but that perhaps the DC direct drive used by Technics isn't the best.  The audio salon I worked at in the 1970's sold Denon turntables, and pushed the line that Denons were better because they used AC rather than DC motors.  We also said that the DC motors worked on a series of pulses (I now think this part is likely incorrect).  I haven't compared the two myself (we didn't have a Technics in store, we had only Denons and our Mitch Cotter base had a Denon 6000 on it, only now I learn that the official version used the Technics).

But as I was looking at auction sites and reading blogs, it seems that the SP 10 MkII is generally regarded as being better than most Denons including the 6000, and about on par with the DP 80 (which I had never heard of before this month).  The only Denon which might actually be better would be the very very expensive Denon DP 100.

The Technics also has other things going for it.  They sold many of these tables, so service and reconditioning is widely available, and in fact the turntables are easily serviced.  Checking and oiling the bearing is the first think any new owner can do.  Denons are more like closed systems.  You don't touch the bearing at all, in fact it isn't even well known what the Denon bearings are actually like; they're a black box to most people.  So it looks like servicing a Denon would be far more difficult and expensive.

I also like the idea of the separate power supply.  And my newfound thinking, from reading the likes of Arthur Salvatore and listening to idler drive maniacs, is that speed constancy requires good torque.  SP 10 MkII and MKIIa, and MKIII are the torque champions!

I'd also been a little upset to learn that Denon went to using PWM to generate the sine waves used in it's turntables.  I generally think of PWM as an inferior system; it's been poorly used in tuners and amplifiers over the years anyway.

So it was actually only this month that I've moved over to the Technics camp.  Not very long ago, I was  criticizing the use of DC motors as in the Haiku Fan that I returned because it was too noisy.  But then I started learning that DC motors were not so necessarily inferior.  For example, Michell went to DC motors for their latest Gyrodecs, and users say universally and unequivocally that the DC motors are better.

Nevertheless, I had been continuing to look at auctions for the Denons.  Not only have I learned that the DP 80 was a successor to the DP 6000, but also the DP 75, which has better specs than the DP 80 but made to a slightly lower price point.  Either DP 80 or DP 75 would do for a nice contest with the SP 10 MkII.  But by most accounts, the MkII would probably win, and the MKIIA should be even better.

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