If you check 3150 is a perfect integer common denominator at 33 1/3 rpm. There are some easily overlooked issues with interleaving the tracks with respect to both rotational and radial velocity.
I was wondering why my test record used that one.
How about a noise track or sweep with a linear frequency response before RIAA equalisation, to allow direct cartridge measurement without equalisation errors?
I was also wondering about equalized vs not, but that should be discussed with the mastering house. Since they are the ones normally applying the equalization, they would know how easy it is for them to leave it out.
We (Scott) could apply a perfect RIAA curve to the files before they are sent to mastering, but would that mess up their signal flow?
We (Scott) could apply a perfect RIAA curve to the files before they are sent to mastering, but would that mess up their signal flow?
Not sure about that, most cutting heads do not have flat frequency response and use EQ in addition to the RIAA cutting EQ to flatten out their frequency response or more correctly perhaps bring the overall system response into conformance with the RIAA cutting requirements. More likely you would want a mastering house that could tell you what their conformance to the standard actually is, and select on that basis.
Yes, there would be value in asking for the RIAA to be turned off and providing an exact RIAA digitally. I know there are things that have to be corrected in the mastering lathe but I still think in lower audio BW's this is a better solution.
As for high frequencies the STR120 claims 50kHz response and it's a legacy test LP. They must be able to do this now.
Hi Scott,
Yes! 3,150 Hz is it. I still have a 3M flutter meter that I restored. Don't ask me why I did that, 'cause I don't know. I used to use a Leader W&F meter. It would be nice to have it right now.
45 rpm on the flip side? I don't know. Maybe use that for extended distortion tones instead. Give you time to actually do an adjustment for a change.
-Chris
Yes! 3,150 Hz is it. I still have a 3M flutter meter that I restored. Don't ask me why I did that, 'cause I don't know. I used to use a Leader W&F meter. It would be nice to have it right now.
45 rpm on the flip side? I don't know. Maybe use that for extended distortion tones instead. Give you time to actually do an adjustment for a change.
-Chris
I like the idea of a group buy test LP very much.
Besides the price and the content the most important issue is the hole size en centering of the hole.
What kind of specification would be required?
I do life in the Netherlands and have two pressing plants relatively close by that I can ask questions on those details.
We can also consider to make it a double album. As far as I can see their pricing this would result in 50% cost price increase only.
From the second hand record market we can perhaps make use of some interesting distribution options.
To increase the Group Buy size we could post the opportunity in a next stage in the Group Buy development at other websites like Vinylengine and Lencoheaven. Keeping the technical/content discussion here at diyaudio
Regards,
Michiel
Besides the price and the content the most important issue is the hole size en centering of the hole.
What kind of specification would be required?
I do life in the Netherlands and have two pressing plants relatively close by that I can ask questions on those details.
We can also consider to make it a double album. As far as I can see their pricing this would result in 50% cost price increase only.
From the second hand record market we can perhaps make use of some interesting distribution options.
To increase the Group Buy size we could post the opportunity in a next stage in the Group Buy development at other websites like Vinylengine and Lencoheaven. Keeping the technical/content discussion here at diyaudio
Regards,
Michiel
I wonder about that, I can't imagine that every CD-4 discrete quadraphonic release was half speed mastered. Bandwidth requirements for CD-4 playback require response out to at least 45kHz. (The carrier frequency is 30kHz)