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Hulk
11-02-2010, 01:49 AM
A few days ago, I dug out my old Dual CS 528 (http://www.vinylengine.com/library/dual/cs-528.shtml) from storage. The belt has been shredded for over a decade. Now thanks to the power of the interweb, I was able to order a new belt (http://www.turntableneedles.com/Flat-Belt-Medium-DUAL-special-133-Inch_p_3786.html) for $15.95 with free shipping.

Probably nothing special about my old turntable, but I bought it new back in 1981 or 1982. It will be cool to see if I can get it working again. My old vinyl awaits.

I wonder if my needle is cashed, too. I had replaced it a few times over the years. Still has the original Ortofon cartridge, too. How does a person evaluate this?

Hulk
11-02-2010, 02:20 AM
Found the stylus I would need: 542-DEV (https://www.turntableneedles.com/Needle-542-DEV_p_1143.html). Check out the picture I took of the actual needle and cartridge on my turntable. The needle isn't original (although it is correct for the cartridge). The Ortofon/Dual cartridge is the same one that came with the turntable.

Crash
11-02-2010, 08:31 AM
Don't listen to vinyl! It will only ruin your digital listening experiences from that point on. Digital is okay as long as you don't compare it to analog. Listen to records and you will only wonder why you ever let the powers that be steer you towards "perfect sound forever". I'd be all too happy to take all that old vinyl crap off your hands, Matt. :hill:
I just had an epiphany in the last couple of weeks: I replaced the rubber drive belt on my record spinner, first with dental floss and when that experiment seemed fruitful, the floss was replaced with silk thread. Amazing how everything sounded considerably better, something akin to better focusing of a camera lens as well as cleaning the lens some. Just installed some NOS Amperex tubes in both the amp and preamp yesterday for similar gains in listening enjoyment. Old school? Moi? You betcha!! Tell us how the "new" turntable and cartridge sound, Hulk, after you've given the cartridge some break in time. The old cartridge's suspension was no doubt shot, so replacing it and the belt were good things to do.
Happy listening!

60wag
11-02-2010, 09:45 AM
My B&O turntable uses a flat black rubber band to make things go round. I pop the band off the motor and platter when the thing is in storage, (which has been most of the last 20 years.) It's still hanging in there but one of these days I'll be searching for a new belt.

As for the needle replacement, it only wears when you're using it. How many hours are on it? You could look at it with a microscope or and eye loupe to see if it looks worn.

Hulk
11-02-2010, 10:37 AM
As for the needle replacement, it only wears when you're using it. How many hours are on it? You could look at it with a microscope or and eye loupe to see if it looks worn.

I think I replaced it my senior year in college (1987). In the years thereafter, I played a mix of CDs and vinyl. I think I'll give it a try with the new belt and see what it sounds like.

Crash
11-02-2010, 11:00 AM
That a cartridge's stylus is the only wear point is incorrect. The suspension of the cantilever is most usually made of rubber. Rubber deteriorates with time, even if unused. If the rubber suspension is dried up and inflexible, it doesn't make any difference if the stylus has never touched a piece of vinyl.

My B&O turntable uses a flat black rubber band to make things go round. I pop the band off the motor and platter when the thing is in storage, (which has been most of the last 20 years.) It's still hanging in there but one of these days I'll be searching for a new belt.

As for the needle replacement, it only wears when you're using it. How many hours are on it? You could look at it with a microscope or and eye loupe to see if it looks worn.

Crash
11-02-2010, 11:16 AM
Even order harmonics are more pleasing to the ear, expecially second order, not odd order.
Dave, the proof is in the hearing, not in the numbers. Fortunately, I don't have an engineering degree that burdens me to being ruled by hard numbers. ;) Even an engineer could hear the improvement of the silk thread drive belt compared to a fresh factory rubber drive belt. I'll bet, if you tried, you could try the experiement on your own table. You may have to help the platter get up to speed because of the initial belt slippage but once proper speed is acheived, it is maintained. As for direct drive, the specs for wow and flutter are small but the noise and vibration induced into the platter and vinyl by the direct drive motor was huge, in comparison. Numbers in recorded audio have never explained everything about the phenomenon of what comprises reproduced sound that makes us happy and sounds like the real thing.

I should also mention that the belt is exactly why Technics and the Japanese tables went to direct drive. They achieved wow/flutter in the >0.01% region while a standard issue NA or European belt-drive can only do ~0.1%. I'd be surprised if even with a perfectly sized silk drive if your table can come anywhere close to a Technics SL-1200mk3 for speed stability, which could do (if memory serves) 0.005%. My Debut III is spec'd at 0.12% flutter. Point is that a belt drive is not necessarily good or bad, but if it's absolute speed you want then nothing that isn't a feedback direct drive is going to do it. But most people feel that the Technics isn't as 'musical' as the belt drives and it's for the same reason you dislike CDs, the precision is perceived as 'sterile'.

Psychoacoustics of music are interesting. For example when you look at the numbers for tubes they should be terrible, 1% THD, yikes. But being that they are lower order and odd harmonics, so they don't sound harsh and are actually appealing.

Now I agree that 44.1KHz is a difficult limit, but for the sake of argument forget the high frequency sampling artifact problem, just take a 440 Hz test tone for comparison and that you are using a decent DAC that has low slew and no oversampling (thus no additional artifacts). They will both sound the same for all practical purposes, but the analog source will likely sound more pleasing because it sounds more natural. Not even the most gifted singer can hold /exactly/ A above middle-C to parts per thousand and we sorta expect some analog-ness to our music.

60wag
11-02-2010, 11:16 AM
That a cartridge's stylus is the only wear point is incorrect. The suspension of the cantilever is most usually made of rubber. Rubber deteriorates with time, even if unused. If the rubber suspension is dried up and inflexible, it doesn't make any difference if the stylus has never touched a piece of vinyl.


Good point. I thought the suspension was a metal spring. What I know about turntables is 20+ years old - long before rubber cartridge suspensions started to decay.

Crash
11-02-2010, 02:07 PM
Dave, engineering and imagination are what fuel the creation of so many of the products that enhance our lives and that artists use to our betterment. Nothing uncomfortable about that! I'd love to demonstrate the differences between the rubber belt and silk thread to you. It's quite easy as my stand alone turntable motor is moveable making the swap a twenty second task.
Matt, to get this back to your original thoughts, Ortofon celebrated their 90th anniversary in the very recent past and is still a leader in the art and science of cartridge design and manufacturing. In this day and age of digital science advances, it is reassuring that good taste is timeless and that money can still be made from old school thinking. I hope you get the new replaceable stylus assembly - nice feature of a moving magnet cartridge - and hook things up in your system. If you do, let us know your impressions. Don't forget, the cartridge will need some time to break in.

Hulk
11-02-2010, 02:55 PM
Just got a notice that the belt shipped today. :)

Once I get the belt installed and determine that the turntable still works (the motor hasn't seized or something else bad), then I'll plunk down for a replacement stylus assembly. That's this thing, right? Or do I need to buy additional parts?

The place online lists three options:
Needle 542-DEV

Quality Level : D7=Stereo LP tip (0.7 mil Dia.) Downgrade copy $21.95
Quality Level : Aftermarket .3x.7 Elliptical $31.95
Quality Level : Genuine Ortofon DN152E $61.95

Crash
11-02-2010, 03:52 PM
Plenty of info out there regarding the various replacement stylii you mention. The middle priced one would work and the low price one appears to be a conical stylus. Worth the extra $10 if your table is in good shape. Have fun!!

Hulk
11-02-2010, 08:25 PM
So the top one isn't even elliptical? I was confused that they would even offer a non-elliptical needle.

Do you think it's worth the extra $30 to get the genuine Ortofon stylus?

Crash
11-03-2010, 08:01 AM
Get the new belt installed and see how the old Dual works before spending $$ on a replacement stylus would be my advice. Going for the Ortophon stylus at the price Dave found would probably be the best way to go. The reason a conical, on average, creates less wear on a record is because it functions its best without any sort of critical setup. The more exotic stylus shapes can dig more information out of a groove but require careful setup by an experienced hand to function their best.

Beater
11-03-2010, 09:34 AM
i second crash.

it's all a matter of perspective. Take that perspective and add that to the time you will actually be using the turntable, divided by the value you place on that experience.

:)


I know I have one of the closest to tube sounding solid state/digital set ups out there. I only really appreciate it about 20% of the time. The rest of the time it's just there. :(