Riaa curve

Hi Atmasphere
good points you make, Raul will have a field day :-)

This also means, there is no way, but NO way, to do this RIAA circuit other then by a most tedious hand selection and soldering in/out process. In the case of your cutting lathe I've no problem, after all it the one that sets the 'standard'.

But as to phono-pres it means 'bespoke' only! --- and well that just about killed 98% of all phono-pres by then.

Food for thought...

I don't know how good the cutting equalization is...that's why I asked. Atmasphere might know.

If you can hear a 0.1 (or 0.01) dB boost over the range above or below the RIAA break frequency (1000 Hz I think) who is to say that the boost is bad? It might even compensate for error of the speaker (although 0.1 dB would not be enough to do that).

Raul...Your efforts to achieve perfection are an excellent example of overdesign. Overdesign is a common fault of engineers...I know: I am one.

Remember the saying...

"In every program there comes a time to shoot the engineers and get on with the job".

Eldartford, when dealing with calibration of a cutting lathe, the speakers are not part of the equation. To answer your question to Raul though: we are, 'we' meaning the people who make this stuff to standards like this. 'We' say its bad when there is a boost or a roll-off that does not conform to the curve. Its not a matter of over-design either. You *can* find parts that a close enough in tolerance that they will do the job.

Atmasphere...What is cut in the vinyl is heard through speakers...the "equation" for what is heard most certainly includes speakers, and a lot of other stuff, and the cutter.

You say that you can find parts that are "CLOSE ENOUGH" to "DO THE JOB". Right on!! That philosophy indicates you don't overdesign.

I am still waiting to hear the frequency response of a typical cutter. and its "pre-emphasis" module.

Eldartford, the unit that I use has bandwidth out to just shy of 30K. The electronics have a bit more than that, but not much (they were designed in the late 60s). I don't think you could say that there is a 'typical' cutter, as they are all designed (like anything else in this world) to meet certain parameters that the designer felt was important.

I chose the unit I did based on hearing the LPs that it was know to have made, and also for the fact that I can get our amplifiers to drive the cutter as well- resulting in the first vacuum-tube transformerless cutter system.