Why do we use RIAA?
To kick off, and this is a response to forum user “Roggies” request for a schematic for a budget quality tube pre-amp for MC cartridges.
Unfortunately MC never has a cheap solution and that’s the bottom line. MM may be getting better but phono die-hards are still going to have to dig deep if they want to belong to the elite.
We won’t get into a debate about which is better, tube or SS but on a spec level there are some incredible op-amps around which do an incredible job to amplify low level signal from vinyl but of course we have the tube purists.
The RIAA signal is part of the recording/playback process:
- Pre-emphasis, amplifying the high frequencies and attenuating the low frequencies on record.
- De-emphasis, amplifying the low frequencies and attenuating the high frequencies on play back.
This equalisation reduces groove width on record and playback which then reduces wear. Pre-and de-emphasis is found in magnetic tape recording and FM transmissions/receivers as well.
As a rule, and I found out the hard way, *one tube pre-amp is not necessarily the same as the other. Especially when it comes to vinyl reproduction. In some cases the most expensive part to any pre amplifier is the design of the phono input which has a very low signal or voltage level with high input impedance. This gives rise to all sorts of unnecessary noise, hiss and hum. Which modulates the best of signals.
Tube pre-amplifiers are quoted as being the best for vinyl, often due to their marriage many years back. This may be true of course. A lovely design I think is from Bruce Heran – the Groovewatt. The power supply needs to be good but moreover, follow the author and builder’s guidelines – they are atypical of using common sense and good practices.
A good quality pre-amplifier is going to burn a hole in your pocket. *Best to listen to a high quality MC/MM pre-amplifier first and then decide on what steps to take. See Trichord Dino. I have listened to vinyl through various amplifiers through the years, all fit and able but one day I just happened to be in the presence of some Bose Bosem Buddies (bullshit baffles brains – the BBB or triple B) and they had a Trichord Dino+ and my heart burst. Well of course they had excellent presses and wow did they sound different to what I was accustomed to. And this was just the other day. 🙂
And maybe that’s the solution – don’t make comparisons, you may already have all that it takes. Reaching for the sky means reaching below, getting out the wallet. Good quality vinyl reproduction is not just an art or science – it becomes very expensive.
So unfortunately there you have it – unfortunately there’s nothing like a cheap good quality phono system.
Great read here: