Nobody said it was impossible. It just isn't a particularly effective approach and it makes a mockery of your stated claim to use "as few additional passive as possible". In order to come up with something new it often helps to understand what has gone before.
BTW, there was article as far back as 1994 that used a MC head amplifier in conjunction resistor I/V for a CD output.
BTW, there was article as far back as 1994 that used a MC head amplifier in conjunction resistor I/V for a CD output.
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How close to an inverse of the actual onboard RIAA network do you think it will be?
So why the he-- are you mucking around with the phono inputs on your preamp ?
Or do you just want to put the horse behind the cart ?
Seriously I cant think of a worse way to get a cd players signal into a preamp.
Maybe also try i/v with OPA602, OPA604, OPA1611, AD8597
Tda i GUESS can work into 10ohm, it will just sound lethargic, it is all there in Broskie text
A phono could be transformed into a inout iv machine with substantial modifications, just would not be worth it , gut it completely, reuse the tube sockets???
Tda i GUESS can work into 10ohm, it will just sound lethargic, it is all there in Broskie text
A phono could be transformed into a inout iv machine with substantial modifications, just would not be worth it , gut it completely, reuse the tube sockets???
Do you have some constructive info you can share or do are you just bored and trolling for self amusement?
Ummmm... Nope. I am not going to trash my Convergent Audio Technology preamp. I'm curious not crazy.
There
A MC head preamp is just an amplifier configured for relatively small voltages. In this case it was used for amplifying the small voltage produced by the i/v resistor used with the dac.
Me I'd use a T-switch and a line level input but each to their own.
Reverse RIAA EQ.
https://hifisonix.com/wp-content/uploads/2016/12/Accurate-Inverse-RIAA.pdf
Reverse RIAA EQ.
https://hifisonix.com/wp-content/uploads/2016/12/Accurate-Inverse-RIAA.pdf
You posed a question with incomplete information.
I am trying to find that missing information.
The provided information makes me ask, just what are you trying to achieve.
Incomplete info results in incomplete results.
Summary.
you want to take a cd players output, modify it through a reverse riaa equalisation network, plug it into a preamps phono input, that applies a riaa equalisation curve.
But you say you want the best possible most direct signal from the cd player to the preamp.
In short, your trying to reinvent the wheel, possibly without understanding the basic concept of a wheel.
I'm trying to help you in the most efficient way possible, if that makes me a bored troll, then so be it.
Did i miss something ?
You can purchase that CAT preamp boards for 30$ for diy audio, I do agree that with a name like that commands a premium price...
There was a French company, some time in the 80-ies, which manufactured a box to be placed between a CD player and a phono stage. Obviously an anti riaa with an attenuator. I recall significant enthusiasm in the audio press at the time.
Digital used to sound so godawful in those days that extending the signal chain in such a ludicrous way might have indeed masked some digital nasties with sweet analogue distortion 🙂 Dithering in reverse.
Today? Dunno really. People seem to really dig adding distortion/noise generators to their digital rigs, so a phono stage can easily be the ticket.
Digital used to sound so godawful in those days that extending the signal chain in such a ludicrous way might have indeed masked some digital nasties with sweet analogue distortion 🙂 Dithering in reverse.
Today? Dunno really. People seem to really dig adding distortion/noise generators to their digital rigs, so a phono stage can easily be the ticket.
Looking at the opening post and the thread title, I have the impression that the signal is to be taken straight from the TDA1541's current output rather than from the voltage output of a CD player. That is, this circuit and the phono amplifier replace the current-to-voltage converter and analogue reconstruction filter of the DAC.
I doubt the signal would reach properly due to the ground return is used to settle the current out,
This will cause the dac to have problems, the IV should be as close as possible to the chip out.
This will cause the dac to have problems, the IV should be as close as possible to the chip out.
I don't know how accurate the RIAA correction of the phono preamplifier is, but the circuit I posted will be rather inaccurate for three reasons:
1. It will be hard to get that 0.1 ohm accurate
2. The component values are for now estimated rather than calculated
3. I tried to add a second-order Butterworth roll-off above 40 kHz, which causes a loss of about a quarter of a decibel at 20 kHz
You can do what I did.
Build a passive reverse RIAA circuit and drive it from your phone. Then listen to the phone mp3 files through the phono vs AUX.
I built mine to tune the RIAA EQ to the AT-VM95ML cartridge. But it will work for this as well.
Build a passive reverse RIAA circuit and drive it from your phone. Then listen to the phone mp3 files through the phono vs AUX.
I built mine to tune the RIAA EQ to the AT-VM95ML cartridge. But it will work for this as well.