Test LP group buy

[lcsaszar]

This is a spinoff from the Turntable speed stability thread. Here we can discuss the technical details and logistics of a future test LP creation and group buy. Especially:

- Signals of the tracks at both sides
- Tools for signal generation
- Selecting the mastering/pressing company
- Organizing group buy
- Options (half speed mastering, etc)
- Any other ideas

We could have a brainstorming what type of test signals are available on other test discs, what of them are useful, what is missing. I believe it should be a measuring tool, so e.g. L/R channel identification and the like are unnecessary.
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Suggestion of tests by Pano
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Track list by luckythedog
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Collaborative folder on Google drive
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Sign-up sheet on Google drive
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Tracklist on Google drive - updated by Pano (see latest version below)
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Test LP Progress Tracking
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Updated tracklist by Pano

 

[davidsrsb]

We could do with a group buy of a new test record. Many of the existing ones are badly mastered or pressed

 

[luckythedog]

Many of the existing ones are badly mastered or pressed

No sign that's the case here.......and, more generally IME, most test records start life fine and good. Perhaps with the exception of attention to hole size/centring.........

LD

 

[scott wurcer]

No sign that's the case here.......and, more generally IME, most test records start life fine and good. Perhaps with the exception of attention to hole size/centring.........

LD

In case anyone is interested 180g hi-quality vinyl costs about $11@ at a min quantity of 100. One might also at least get someone's ear that the hole size/centering is important. If 20 folks are considering buying one test LP at $40-50 plus shipping a group buy of just what we want might make sense.

Just a thought, 20 members each get 5 copies at about $65 or so with postage.

 

[billshurv]

I would have thought Jason might want to offer this in the store? Worth asking him anyway. The setup GZ use New mastering system GZ Vinyl seems particularly useful as you can visualise the grooves before cutting.

But yes I would stump up, given I am too young to have a stash of originals like you 😉

 

[luckythedog]

In case anyone is interested 180g hi-quality vinyl costs about $11@ at a min quantity of 100. One might also at least get someone's ear that the hole size/centering is important. If 20 folks are considering buying one test LP at $40-50 plus shipping a group buy of just what we want might make sense.

Just a thought, 20 members each get 5 copies at about $65 or so with postage.

I'm reminded of the film, 'A Might Wind' where they had a record pressed without a centre hole to save cost on a budget label.............

A Mighty Wind Official Clip - The Record Had No Hole - 2003 | Fandango MOVIECLIPS

But it would be an option to miss out the hole drilling stage, I suppose....😉

For my sins I'm a musician in a band, and last year we had a run of 1000 vinyl records pressed. Mastering was by Pete Norman at Finyl Tweak, and it really was a great job. It matters where it's done and who does it, for sure.

I should have put a few test tones in there..........

On the plus side, I still have 996 virgin copies of the same record for test purposes 🙄

LD

 

[Tiido]

I'd be happy to get my hands on a nice test disc. Freq sweeps, resonance tests, stereo separation tests and other things would be very nice to have. And 45rpm is of great importance to me also, 12" 45rpms <3

One time I talked to a local vinyl manufacturer VinylPlant and I got a quote for 12.16€ per disc for 100 and 4.98€ for 300. Includes DMM stampers, test presses, printed labels and sleeves, packing and packaging etc. The quote was for a nice music release, If fancy color printing and other goodies is to be discarded the cost could decrease a bit. Shipping is pushing the cost per disc to 20...30€ range regardless.

I have no idea about their machines technical specs though.

EDIT: GZvinyl seems to beat everything though, very fancy tech and prices ~

 

[fasterbyelan]

On the plus side, I still have 996 virgin copies of the same record for test purposes 🙄

LD

I suppose the band had the first 4 copies 😀😀

 

[luckythedog]

I suppose the band had the first 4 copies 😀😀

Precisely.......................😉

LD

 

[Pano]

Maybe a DIY test LP is a keen idea. Worthy of its own thread, of course. If we can discreetly get other audio forums interested there should be enough demand to make the price reasonable.

One nice thing about an open source test LP is that we could publish the original signal files, as well as the mastered files - if that's a help.

 

[fasterbyelan]

Maybe a DIY test LP is a keen idea. Worthy of its own thread, of course. If we can discreetly get other audio forums interested there should be enough demand to make the price reasonable.

My own thoughts exactly, l would be happy to promote the Test LP on the Lenco Heaven Forum as I have been quite active there.

I think most of us have at least 1 test lp so the one we hope to produce need not repeat phase checks, tracking torture tests ect ect. Something very well made is essential (with an accurate spindle hole position!) My own initial thoughts on the tracks would be -

3150 Hz test tone for speed testing and cartridge setting up

Pink and White Noise tracks, the latter to overcome the -10db per decade decrease in energy of the former.

20 - 20Khz Sweep x 2, one with equal energy per octave, one with equal energy per hz.

Silent Track

Those better qualified than me will tell me if the above are possible but my thoughts are for a test lp that can be used for testing cartridge output and frequency response as well as TT and arm performance. Whether there is any benefit to be had from using 45rpm as the LP's speed, again others can comment. (1 side 33 rpm, the second 45 rpm?)

 

[scott wurcer]

3150 Hz test tone for speed testing and cartridge setting up

Pink and White Noise tracks, the latter to overcome the -10db per decade decrease in energy of the former.

)

All tracks could be generated by computer and verified and exact digital versions could be available as a download. There also should be a pre-discussion of things that were not possible in the past like setting exact crest factors on the noise bands or the possibility of including complex multi-tone signals. Though I suspect the fidelity of anything unusual will disappoint.

 

[spaceistheplace]

Maybe a DIY test LP is a keen idea. Worthy of its own thread, of course. If we can discreetly get other audio forums interested there should be enough demand to make the price reasonable.

One nice thing about an open source test LP is that we could publish the original signal files, as well as the mastered files - if that's a help.

Cost can be quite reasonable, even for ~500-1000 units.

When I was doing it RTI was known as the better of the US providers, but they also had a long wait list.

Now that I consider it I find it odd no one has attempted this before.

I think it would be easy to fill up a group buy, especially so if we offered it on Lenco Heaven as well.

Depending on various fanciness I couldn’t see it exceeding $20 or so, which is still less than half some of the modern test records go for.

 

[Pano]

Though I suspect the fidelity of anything unusual will disappoint.

It would be worth talking to the disc mastering engineers about what they see as stumbling blocks to cutting clean test signals. They should have a good feel for what will work and what won't. Cutting heads aren't perfect.

 

[davidsrsb]

Half speed mastering would allow accurate sweep up to about 30kHz. Nothing currently available is accurate to 20kHz.
I was at a HiFi show in KL a couple of years ago and the Ellipson test disc sold in hundreds

 

[anatech]

L/R channel identification is handy to have in a test situation, then there is how much isolation between channels that can be measured.

 

[scott wurcer]

There are several members here that have already dealt with small run LP's and I would hope we could find an engineer that would lend a sympathetic ear toward an obsessive requirement for centering of the hole.

As for tracks one that exists on no test LP's is a reference frequency in one channel and a once per rev pulse in the other. I would recommend a single raised cosine pulse that stays inband since there are simple algorithms to place it in time exactly.

 

[Pano]

Yes Chris, I'd like to have channel ID and crosstalk tests.

I have no idea how much channel separation can be cut into the LP, so we'd want to ask the mastering house about that, and include that info with the test LP.

 

[Pano]

As for tracks one that exists on no test LP's is a reference frequency in one channel and a once per rev pulse in the other.

For the speed polar plot, right?

 

[anatech]

Isn't the standard frequency for speed and W&F test 3 KHz?

-Chris