Hi,
Just try finding the 3.3n Ones and use 3 pcs to make up the bigger cap. It makes the search for cap's easier, you only need to find one value, a small one and you need already 8pcs at least, so it makes buying easier...
Ciao T
Just try finding the 3.3n Ones and use 3 pcs to make up the bigger cap. It makes the search for cap's easier, you only need to find one value, a small one and you need already 8pcs at least, so it makes buying easier...
Ciao T
PartsConnexion has them
Reliable RTE Capacitors
aswell as Percy Audio
http://www.percyaudio.com/Catalog.pdf
Best,
Reliable RTE Capacitors
aswell as Percy Audio
http://www.percyaudio.com/Catalog.pdf
Best,
Hi,
Reliable offers tinfoil. LCR still makes Alu/Polystyrene which you can get for Farnell/Newark.
I have a collection of Tinfoil / Polystyrene Cap's including east german mil spec stuff and various 47n, 62n and 180nF ones, plus a truckload of them old Philips Tin/Leadfoil & Polystyrene ones, that got nixed by Epcos ages before ROHS...
For bragging rights I am still looking for these copperfoil & polystyrene Cap's the Japanese majors used to use in the late 70's and early 80's in their top line gear (including RIAA). I have some 100pF, which don't get me far.
Ciao T
Reliable offers tinfoil. LCR still makes Alu/Polystyrene which you can get for Farnell/Newark.
I have a collection of Tinfoil / Polystyrene Cap's including east german mil spec stuff and various 47n, 62n and 180nF ones, plus a truckload of them old Philips Tin/Leadfoil & Polystyrene ones, that got nixed by Epcos ages before ROHS...
For bragging rights I am still looking for these copperfoil & polystyrene Cap's the Japanese majors used to use in the late 70's and early 80's in their top line gear (including RIAA). I have some 100pF, which don't get me far.
Ciao T
For loudspeakers I really like tinfoil/polypropylene capacitors.. they are calmer and have more resolution than any other Cap..I know off and could not think of using anything else in my loudspeakers..
I will also use them here as output cap....Think I'll look for the REL-caps for the Riaa network...
Still have to sort the better transistor choice for the VAS stage and cascodes...pls forgive me.. I enter into this with not much analog electronics experience..as my background is mechanical engineering (vibration and material) and design...So my knowledge of transistor names and their more specific data is rather limited...
But I do think it's cool to make a circuit, get it to work in simulation and then in implementation...sort of like a new ballgame for me, very full filling to get something in unchartered water to work...
I will also use them here as output cap....Think I'll look for the REL-caps for the Riaa network...
Still have to sort the better transistor choice for the VAS stage and cascodes...pls forgive me.. I enter into this with not much analog electronics experience..as my background is mechanical engineering (vibration and material) and design...So my knowledge of transistor names and their more specific data is rather limited...
But I do think it's cool to make a circuit, get it to work in simulation and then in implementation...sort of like a new ballgame for me, very full filling to get something in unchartered water to work...
The round Blues or the square Yella ?
(me is old record player : www.komponenten.es.aau.dk/fileadmin/komponenten/Data_Sheet/Generelle/KS429.pdf )
I don't want to omit the coupling cap.. I do believe that it is much better than a servo.. as I see the used servo opamp as being part of the circuit... although the placement of the servo you suggest is rather apealing...
All the best amps i have heard contains coupling caps...
Now looking at this.. I do believe that the nature of this transconductance circuit is much stronger than other combinations of a head amp and a following 2. stage...
Funny circuit....but it fits the riaa curve like a match made in heaven.. because the riaa curve compensates for the flaws that a non feedback design usually haves..The gain profile of the riaa makes the otherwise limited circuit..into a high bandwidth low distortion.. circuit with at low component count and a low(lowish) noise.....Looking at it this way makes it understandable why integrated circuits based on feedback will have inferior performance....
On the other hand this circuit need a goooood supply as theres no feedback to up the pssr.. Salas type shunts are one way to go.. Another could be stacked R-C cells like I have in my schematics...I tend to lean at the latter...
A pure passive supply with Schottky diodes plenty of capacitance and a chain of R-c cells..
All the best amps i have heard contains coupling caps...
Now looking at this.. I do believe that the nature of this transconductance circuit is much stronger than other combinations of a head amp and a following 2. stage...
Funny circuit....but it fits the riaa curve like a match made in heaven.. because the riaa curve compensates for the flaws that a non feedback design usually haves..The gain profile of the riaa makes the otherwise limited circuit..into a high bandwidth low distortion.. circuit with at low component count and a low(lowish) noise.....Looking at it this way makes it understandable why integrated circuits based on feedback will have inferior performance....
On the other hand this circuit need a goooood supply as theres no feedback to up the pssr.. Salas type shunts are one way to go.. Another could be stacked R-C cells like I have in my schematics...I tend to lean at the latter...
A pure passive supply with Schottky diodes plenty of capacitance and a chain of R-c cells..
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I do not know if the plan is still to use this circuit also as MM. If so, the BF862 has the advantage of much less input capacitance Ciss of 10pF against 75pf of the 2SK369. The 2SK369 has a higher early voltage though. Your circuit does not suffer much from speed problems so this difference in early voltage should not play a big role i think.
Attachments
Real life JFETs
Did you try to mismatch the input JFETs so that the circuit will use more realistic Idss/Vp/etc variations as they will in real life?
That can/will affect THD and DC offset.
Always good to do before prototyping.
To sweep temp can also be enlightning.
/S
Did you try to mismatch the input JFETs so that the circuit will use more realistic Idss/Vp/etc variations as they will in real life?
That can/will affect THD and DC offset.
Always good to do before prototyping.
To sweep temp can also be enlightning.
/S
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