Riaa curve

Eldartford,
you mentioned the cutting lathe and applied (inverse) RIAA.

I would like to know about % deviation found with well regarded 'commercial' phono-pres (not boutique audio).

Looking at the few test graph showings in audiophile’s measurements --- "With all this going on, extreme accuracy of the RIAA equalization seems unnecessary to me." --- it seems some more manufacturer sharing this opinion.

We all know that accuracy will be nice to have in deed, but is it THE prime design parameter I seem to hear it is? Aren't there other much more important ones?

In other words: will it render another product much inferior just because it does not go to the ultimate in this RIAA matter?

Again, (yes, my system sux) listening to my 390S CD and then to the same on LP, I can hear NO colouration with a +/- 1% spec. We also know there are units out there with more than 1% deviation (and not too cheap either).

Eldartford, you are right about that process, but the producer of an LP would never have the EQ of the RIAA messed with! Usually the issue is a private studio and producer have made a recording. They want an LP, so they send the tape to someone who can do that. Usually they also send a tape of test tones made on their tape machine, so the LP manufacturer can set his tape playback to match the calibration of the original tape machine. Then he makes the LP.

The producer then gets a test of the LP and listens to it. He may ask for changes in the tape playback calibration (this is something *very* different from EQ, BTW) in order to get the LP to sound more like it did when the recording was made.

If the LP is being pressed in a different country, this process is often broken. That is one reason why it is so important to get an LP that is pressed in the country where the recording was originally made!

It is a tricky process, no doubt, and full of errors, but one thing that no-one ever seems to mess with is the EQ curves. For the most part, there is a very genuine effort to get the LPs to sound like the playback of the master tape.

Atmasphere...Agreed that no one would deliberately screw with the RIAA equalization. My original point was that 0.1 dB is readily obtainable and more than adequite. 0.01 dB is a waste of effort. IMHO.

Eldartford, it might be, but in the world of high end, the difference between HIFI and the ability to sound like real music exists in the nuances. That is why there are Teflon caps, high precision resistors, care in grounding layouts, spec-ing out the gear octaves beyond human hearing, use of high purity wires, balanced operation (in our case anyway), non-ferrous chassis, *tubes* and whatnot.

We are trying to make it sound real. All designers probably have a blind spot, usually a focus on what they think is important :) so you will see a wide variation in designs as a result. It is the mark of a good designer to know what specs are 'negligible' and which ones are really important that *look* negligible. I don't think I am in a position to really judge exactly what that might be, because like everyone else, I have my blind spots too. In the case of EQ, we can spec the EQ components within 0.05% pretty easily, so I don't think hitting 0.01% should be all that much harder.

Dear Eldartford: +++++ " original point was that 0.1 dB is readily obtainable and more than adequite.... " +++++

adequite?, for whom?. Certainly your " goals " are really different that the ones in other people like me.

How do you know what is adequite and what is not if you never had the opportunity to compare about?, your statement make no sense.

IMHO the mediocrity that surround the audio industry has its origins ( between other things ) in the mediocrity of the whole audio industry goals, there is almost no attitude to be better and why to worry in be better when the customers don't ask for more.

Fortunatelly there are designers like Ralph, my self and others that still care to growing up making better designs out of the mediocrity of the whole audio industry in where the customers are the main part.

I respect your attitude in the RIAA subject, it is an easy one where you don't really cares about where you don't ask for anymore where you don't ask for a better audio items and that attitude is fine with me and fortunatelly does not affect my spirit to improve and be better.

Regards and ejoy the music,
Raul.