if you want to build it yourself, you can either use the paper I believe Nelson Pass wrote.
The circuit is basically a standard circuit which is also the same scheme used on the ONO/XONO MM section for instance.
I would indeed recommend to substitute the OP AMP with the Dexa Discrete module
DEXA Technologies Discrete Audio Op-Amp
I had an impressuive result. Maybe you can try it out and give me your feedback as well
The circuit is basically a standard circuit which is also the same scheme used on the ONO/XONO MM section for instance.
I would indeed recommend to substitute the OP AMP with the Dexa Discrete module
DEXA Technologies Discrete Audio Op-Amp
I had an impressuive result. Maybe you can try it out and give me your feedback as well
Tanks for the imput
I have built V2 beta with IRC resistors (tanks FDW)
and I have done the best I could to match the RIAA parts 1%
Transistors are the best closest I can get with running a batch of 1000 on a curve tracer (same problems with "toy" calibration and PNP here)
For Bulk and Imput I have used Panasonic FM so what wuld be better?
Yes I like the idea of Battery still same Jhonson noise there (LAC) and the bughers never charge at same rate so one end up with offset on suply rails.
I trust Joachim with the servo and to replace that with a discrete is way out of my cabalities.
I have built V2 beta with IRC resistors (tanks FDW)
and I have done the best I could to match the RIAA parts 1%
Transistors are the best closest I can get with running a batch of 1000 on a curve tracer (same problems with "toy" calibration and PNP here)
For Bulk and Imput I have used Panasonic FM so what wuld be better?
Yes I like the idea of Battery still same Jhonson noise there (LAC) and the bughers never charge at same rate so one end up with offset on suply rails.
I trust Joachim with the servo and to replace that with a discrete is way out of my cabalities.
Interesting point regarding the Offset on the rails.
I Haven't found that to be a big issue on final sonic performance.
Try it yourself and you will see.
For the Discrete op amp, you don't have to do anything other than having a little socket on the op-amp and buy the module I have linked. It is pin-drop replacement so you just need to put it on and verify that everything works just fine and you are then good to go.
For capacitors, here my recommendation is: if you are using the regular transformer/bridge combination, use blackgates or Panasonic FC (I have never tried the FM vs FC).
Use 0.22uF Auricap Bypass on the bulk and on board as bypass and bypass the heavy capacitor on the signal path.
Other thing as if you are using battery, I recommend to use a 1/2uF Teflon/Film cap there, the difference is pretty significant.
Just a disclaimer: I have discover that Film cap on the PSU are going to yeald to a good result ONLY if the circuit is extremely good.
In other words I test this to evaluate performance on my audio circuit as well.
If circuit accepts this last mod, it is the paradise!
The servo deals with close to DC...and is shielded benhind highimpedance mirrors... Can't imagine that any discrete opamp would make any change... Also the riaa is backwards...where induction normally gives treble loss, here it gives treble boost... So I believe that you should be kind of carefull in throwing big money into things... Better may not be better at all.
Resisters arround the input may be changed to low noise types. Best is bulk metal foils, but going up as size to 1 or 2 watt may lower noise just as much.
Resisters arround the input may be changed to low noise types. Best is bulk metal foils, but going up as size to 1 or 2 watt may lower noise just as much.
Makes quite a difference, compared to something intended for AC.
(Stefanoo may need a servo for his servo)
I guess trying doesn't hurt.
The module are only $80, and can be re-used for other project as well.
Miib: have you tried to change caps on the RIAA to assest your statement?
It sounds like you already tried to compare good quality cap and medium and found no difference at all.
If thst is the case, then I wouldn't even bother in trying.
FM is better ESR than FC as far as I konow so no problem there
OK plenty of space on botom of boards for By pass so that is a possible one only snag I see with using designer caps there is that they work quite well as microphones.
(Try to tap a M cap Supreme ?)
What Capacitor on signal pat? only thing I see is R12 the rest goes down to ground.
HOT HERE SO Much happening while I am tiping
OK plenty of space on botom of boards for By pass so that is a possible one only snag I see with using designer caps there is that they work quite well as microphones.
(Try to tap a M cap Supreme ?)
What Capacitor on signal pat? only thing I see is R12 the rest goes down to ground.
HOT HERE SO Much happening while I am tiping
Don't be fooled by the fact that the capacitor goes to GND.
It is acting on the input signal, thus it can be considered on the signal Path.
Quality there should matter, but again, I will leave all this consideration to the designers of this circuit and put my off my comments until I get the board and had time to try it out several solution.
NOW THIS make loads of sense to me
Some like this ? http://docs-europe.electrocomponents.com/webdocs/00a6/0900766b800a602a.pdf
Stefano.. please don't be such a wise guy...
I have built 3 different versions of this circuit, I have developed most of it after Joachim's intial concept... I can asure you that i works in at totally different manner than most other circuits. primarily because the RIAA is a shunt and works in parallel to the signal and not as ordinary circuits in series with the signal.. because of that what we're seeking it also different. So unless you have tried this circuit, don't be so sure you're statements are valid..
A also the servo works different compared to normal servos as its integrated in the main CCS delivering current to the system.. The servo has less influence than the resistor setting the current.
I have built 3 different versions of this circuit, I have developed most of it after Joachim's intial concept... I can asure you that i works in at totally different manner than most other circuits. primarily because the RIAA is a shunt and works in parallel to the signal and not as ordinary circuits in series with the signal.. because of that what we're seeking it also different. So unless you have tried this circuit, don't be so sure you're statements are valid..
A also the servo works different compared to normal servos as its integrated in the main CCS delivering current to the system.. The servo has less influence than the resistor setting the current.
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bksabath...
some like this.. Cost you an arm and a leg though...
http://www.vishaypg.com/docs/63140/var.pdf
some like this.. Cost you an arm and a leg though...
http://www.vishaypg.com/docs/63140/var.pdf
NOW THIS make loads of sense to me
Some like this ? http://docs-europe.electrocomponents.com/webdocs/00a6/0900766b800a602a.pdf
Never seen those, anyway, they have high TC so I wouldn't use them on a high gain circuit.
bksabath...
some like this.. Cost you an arm and a leg though...
http://www.vishaypg.com/docs/63140/var.pdf
Yes just the ones I was dreaming about (no kiding ask Brian)
they make same with coating so they don't breack as easy
Big question is still where?
The 33 R on the imputs Most probably
The 120 on the mirrors Maybe.
Now considering that Just the 16 for the imputs cost more than my cartridge which cost more than my arm and TT combined this need same serious consideration
(how much screaming can I take if she finds out and is it worth it?)
would same similar at half the price or a quarter go hand in hand with diminishing return?
bksabath...
some like this.. Cost you an arm and a leg though...
http://www.vishaypg.com/docs/63140/var.pdf
I would even consider the lower end Naked TX2352 they run 1t $6-$8 each but in the right spot they can make the difference.
Stefano.. please don't be such a wise guy...
I have built 3 different versions of this circuit, I have developed most of it after Joachim's intial concept... I can asure you that i works in at totally different manner than most other circuits. primarily because the RIAA is a shunt and works in parallel to the signal and not as ordinary circuits in series with the signal.. because of that what we're seeking it also different. So unless you have tried this circuit, don't be so sure you're statements are valid..
A also the servo works different compared to normal servos as its integrated in the main CCS delivering current to the system.. The servo has less influence than the resistor setting the current.
woo woo....let's take it easy please
I asked you a simple question:
have YOU tried different quality capacitors and resistors to assure that your statement is correct?
I understand it works totally different but have you tried it?
You can have the equation of how it works but you don't have the equation of that equates to the final sound quality.
At the end I am sure you are right.
I try a lot of things anyways although solution seems to be obvious, and quite a few time I have been proved wrong thus I have learned not to be sure of things that I can't prove with a clear equation.
That is the interesting part of the development of an audio circuit.
The ear is your final judge and unless this is not fully understood, we will see commercial product going around for a lot of $$ which sound is not cutting edge.
Yes just the ones I was dreaming about (no kiding ask Brian)
they make same with coating so they don't breack as easy
Big question is still where?
The 33 R on the imputs Most probably
The 120 on the mirrors Maybe.
Now considering that Just the 16 for the imputs cost more than my cartridge which cost more than my arm and TT combined this need same serious consideration
(how much screaming can I take if she finds out and is it worth it?)
would same similar at half the price or a quarter go hand in hand with diminishing return?
What cartridge/turntable/arm do you have?