Nice turntables. Attached picture is an absolute requirement.

[JP]

Also, I think the lowest possible capacitance would help in this case. 100 pF total is possible if cabling is optimized.

(Would be interesting to see the V15V JICO SaS/B with 30k)

I need to measure C end-to-end à la the @SIY method. Present calculation is measured arm cable, measured interconnect, parasitic of the board from the designer, data sheet for the opamp, and some allowance for connectors, rounded up to the nearest quarter nF. The interconnect is only 14”, though STP. Even so, shaving a few inches off isn’t going to matter.

I’ve SAS B, S, R, and Z for the V. Some day I’ll measure them all and play with loading. It just never makes it on to the priority list.

 

[anmpr1]

I’ve SAS B, S, R, and Z for the V. Some day I’ll measure them all and play with loading. It just never makes it on to the priority list.

Is the brush on the Jico Shure replacement stylus oil damped, like the original Shure? Or is it simply hinged? I've been curious about that feature.

 

[LTig]

Since I hadn't used my TD-125 for decades, I decided to clean it up and restore it to its original glory prior to offering it up for sale. The refurbishment turned out so well, and the turntable works so perfectly that I decided to keep it, even though I have no space in my current equipment rack to display it.

View attachment 171549

View attachment 171550

I didn't know that there were records running with speed 16.

 

[Thomas_A]

Is the brush on the Jico Shure replacement stylus oil damped, like the original Shure? Or is it simply hinged? I've been curious about that feature.

Mixed bag. But I have succesfully added som silicon oil to add damping to the JICOs.

 

[Laserjock]

 

[sergeauckland]

I didn't know that there were records running with speed 16.

16 2/3 was used for talking books for the blind, and similar, essentially speech-based, but never became mainstream, As far as I know, it was never used for music.
S

 

[anmpr1]

I didn't know that there were records running with speed 16.

In all my years, I don't think I ever owned a 16 rpm record. But all the old changers had that speed. I think it was mostly for speech and/or audiobook type records. That speed was deprecated, along with 78. However, 16 and 78 was/is important for three reasons:

1) 78 is great for using your Discwasher, saving a lot of time and rotations, before playing your record.

2) Moby Grape's Wow record had a cut at the end of side one (or was it side two?) where the Grape spokesman told the at-home listener to get up and change the speed of the record player to 78. Then, a ukulele tune introduced by Arthur Godfrey, and sung by Skip Spence began. In order to enjoy that bit of ersatz nostalgia, you had to have 78rpm. As far as I know, Moby Grape never cut a tune at 16rpm. But if you did enough LSD, it might have seemed that way.

3) One of Frank Zappa's things, might have been Lumpy Gravy, featured a section of a curiously disjointed tune played at 45rpm speed, but cut at 33 rpm on the actual record. If you knocked it down to 16 rpm, you could hear it at 'regular' speed.

 

[USER]

Nothing to laugh about. Personal anecdote: I owned a Denon DP-75 with their DA-304 (I think that was the model) tonearm. On it's factory birchwood (I think that was what it was made of) base. At the same time I also owned the first version of your DP-30. The one with the S shaped tonearm. Both arms had a plug in universal shell, so you could swap cartridges and compare. Not strictly A/B, but pretty easily accomplished.

The little DP-30 with it's resin base sounded just as good, if not better, than the expensive DP-75. The latter had quartz PLL, special damped platter, a 'sophisticated' separate tonearm with special 'damping', and was certainly nicer to look at. But didn't sound any better, to my ears. If I can attribute it to anything other than imagination, I'd say the 30's resin composite base was less resonant than the wooden 75.

Great story. It's a fabulous turntable and in no way did I mean to imply that it was worse than the others. I'm keeping the DP-35F because of its automatic features, which, day in and day out, are going to keep me using the medium longer. And I simply adore the 1970s industrial aesthetics of the Sony and it seems to be running at slightly better specs than the fancier turntable I sold. Someone is going to be absolutely thrilled with the DP-30L when I finish up.

Did you see these DP-30L measurements here?

Fun with vinyl measurements

Hello, as I posted before, I tried a new approach to measure Wow&Flutter and failed. I used a optical encoder disc with 2000cpr: Setup on a real turntable: But the encoder is not precise enough to obtain noise-free measurements. So in the next step I will try it with a gyroscope, very...

www.audiosciencereview.com

So, so good. I'm a bit above that at around 0.06 RMS% (DIN) with 0.14% quasi-peaks. The test record (Tecet Vinyl Check) is not super high quality (not that there are really any around), but other turntables have shown better numbers on that same test record, so I know something is off. There are some marks on the platter inner wall the turntable reads to keep speed, so I may have to replace it if a good one pops up. Though I think its more than that.

Essentially, when I knew I wanted to replace my boutique belt-drive turntable, I realized that I wanted to go with either a new Technics or an 80s DD classic. The going prices of the former led me to try out several of the latter, which I knew had to be serviced no matter the condition stated on the adverts. I've learned a lot so it has been worth it. I really knew nothing about servicing until a few weeks ago and I have a long way to go.

Keeping these from a landfill--and hopefully preventing them from ever ending up in one--also makes me feel super good about this whole endeavor.

 

[restorer-john]

Here is what is in my home right now, lol.

View attachment 171553View attachment 171554View attachment 171555View attachment 171556View attachment 171557

I sold off an modern boutique turntable and got some older classics that I am restoring. I'll give to friends what I won't keep. Plenty of money left over from the sale too! The Denon DP-35F will be my new turntable. I realized that I have a soft spot for the Sony PS-X50 and so will probably keep it as well. The other is a Denon DP-30L II and the Dual 504 is actually the first turntable I bought back in 2004.

It is fascinating to have an assortment of technology in front of me which allows me to trace the development of what I think is the golden age for this tech. The Dual has only 1 capacitor (!!!) and is pretty brilliant in its simplicity. The 35F has an electronic servo-tonearm.

The Sony is almost ready though I can't figure out how to open the motor in order to clean and lube the bearing. The 30L II is almost there but I am missing something as I know W&F can be much, much better. I think I have the Dual running better than spec.

View attachment 171560

The DP-30L/ or MK2 is very sensitive to the head placement in relation to the mag stripe. I use a business card measured with a micrometre to get the exact gap. Loosen the screws, push up against the business card/ platter and adjust.

 

[USER]

The DP-30L/ or MK2 is very sensitive to the head placement in relation to the mag stripe. I use a business card measured with a micrometre to get the exact gap. Loosen the screws, push up against the business card/ platter and adjust.

Wow. Thank you, John. I just did a quick pass with the first card I found and the measurements improved to the following:

I'll go through the service manual and adjust to the specified gap as well as I can later today.

 

[Twitch54]

VPI Aries3, super platter, perf ring, SDS
Benz Micro Gulwing
Fosgate Signature phono-pre

 

[JP]

Wow. Thank you, John. I just did a quick pass with the first card I found and the measurements improved to the following:

View attachment 171876View attachment 171877

I'll go through the service manual and adjust to the specified gap as well as I can later today.

I was going to buy that test record yesterday. I wasn't able to think of anything else I wanted that'd add $20 to the cart to get free shipping, so I didn't. A lot of people use the pink noise tracks for measuring cartridge FR, and I was curious the accuracy. Just not curious enough.

 

[restorer-john]

Wow. Thank you, John. I just did a quick pass with the first card I found and the measurements improved to the following:

View attachment 171876View attachment 171877

I'll go through the service manual and adjust to the specified gap as well as I can later today.

The fact your two rotations on the polar plot are tracking perfectly likely means you've hit the limit of that test record. It clearly has a very slight eccentricity, but overall really good.

 

[USER]

I was going to buy that test record yesterday. I wasn't able to think of anything else I wanted that'd add $20 to the cart to get free shipping, so I didn't. A lot of people use the pink noise tracks for measuring cartridge FR, and I was curious the accuracy. Just not curious enough.

All the W&F samples I have sent you privately have been measured with it. Its main problem seems to be a big centering issue (though I have gotten better at placing it as best as I can).

This is the best I was ever able to get with that record and a Clearaudio Concept belt-drive turntable.

And this is the DP-35F

The rotation speed matching terrific!!!

Centering the DP-30L better just now led to this, so there's a lot of wiggle room with the measurements. Wish there was a solid test record out there!

 

[JP]

You can also index it for the polar plot. Grab a sample, rotate the record 180, grab another sample. I then zoom-in on the tracks in the DAW to get the exact same starting and export what I want to measure from there. It'll be very obvious what's from the test record, and what's from the motor/bearing.

 

[restorer-john]

@franspambot The DP-30LII head spacing is 0.2mm. After adjustment, spin the platter slowly by hand and listen to make sure the head doesn't contact the inner surface. If there is any bearing play, it will also reflect in the measured results. (often people moved those poor TTs with the platter on...). You can adjust the head spacing with various thickness pieces of card in order to obtain the 7mV peak input and the correct output at the TA-7122 (pin6):

The TCA-955 either works or it doesn't and the caps around it aren't critical IME as long as they in spec.

Also, you probably know this, the 120V version of the TT has a live (mains) motor control and driver stage, isolated via optocoupler to the low level circuitry- be careful if probing waveforms with a 'scope.
The 230V version is totally transformer isolated with a dedicated 100V secondary for the motor- much safer when poking around.

Let me know if you have any other issues, I have several of these TTs.

PS. The PSX-50 rear left hinge crack will break through that lid unless you take it off the spring hinges. The Denons do that too! Makes a huge bang when the perspex lets go.

 

[JP]

@restorer-john, any chance you've a DP-100 service manual stashed away somewhere? TX-1000?

 

[restorer-john]

DP-100 service manual stashed away somewhere?

I think I do. I'll go through the S/M box in the storeroom next time I'm up at my storage units.

Definitely not the TX-1000 sorry.

 

[JP]

I think I do. I'll go through the S/M box in the storeroom next time I'm up at my storage units.

Definitely not the TX-1000 sorry.

That would be absolutely amazing.

 

[USER]

You can also index it for the polar plot. Grab a sample, rotate the record 180, grab another sample. I then zoom-in on the tracks in the DAW to get the exact same starting and export what I want to measure from there. It'll be very obvious what's from the test record, and what's from the motor/bearing.

You mean like this?