Allen uses Rel Caps in the Sonics speakers he makes in Berkeley designed by me.
Unfortunately i have not heard the new versions so far. Last time i was in the states we had a prototype playing that i had build with Brian for the CES show. Both Brian and Allen say that the series production speakers sound much better without changing the circuitry i designed but using choosen parts. Also Stig called me up from Japan and told me that the "new" spaekers sounded just fine. I know these guys since 2o years and i trust them. I myself gave up a long time ago to "measure the sound of passive components". I hear diffences and i know that they exist but i simply did not find a set of measurements that tells me how they sound.
Unfortunately i have not heard the new versions so far. Last time i was in the states we had a prototype playing that i had build with Brian for the CES show. Both Brian and Allen say that the series production speakers sound much better without changing the circuitry i designed but using choosen parts. Also Stig called me up from Japan and told me that the "new" spaekers sounded just fine. I know these guys since 2o years and i trust them. I myself gave up a long time ago to "measure the sound of passive components". I hear diffences and i know that they exist but i simply did not find a set of measurements that tells me how they sound.
I decided to set up a listening test. I am designing a high input impedance, high speed, low distortion buffer at the moment anyway. So i will use a silver contact switch and 2MOhm resistors. This goes into the buffer. The cap value will be 10nF so this forms a high pass with a -2dB frequency of 10Hz.
More later as John whould say.
More later as John whould say.
Shemp never gets any respect.
There's a reason for that.
Ok, Joachim, let me go on, as an example of dialogue between one audio designer and another: Joachim, to get a quick and easy evaluation of what a Rel RT polystryrene cap would do in your application, just get Allen to order 2 or more .01 uf RT caps from Michael Percy, and have him send them to you. They should cost about $3.50 each, matched to 1% of each other. (abs value, within 5%).
These caps may be old stock or new stock. Old stock used Beyer polystyrene (clear)
New stock uses Chinese Polystyrene (amorphous and opaque) Both are good. Certainly close enough for this test.
Volume purchases can be done directly with the factory, but that is another story.
These caps may be old stock or new stock. Old stock used Beyer polystyrene (clear)
New stock uses Chinese Polystyrene (amorphous and opaque) Both are good. Certainly close enough for this test.
Volume purchases can be done directly with the factory, but that is another story.
Ok, i will get me a pair. I talked to the Rel designer on the last CES and he was very friendly and open so i may get some samples from him or i buy them from Percy.
Anyway, thanks for this sugestion. If i can get better sound that way i am even more happy.
Anyway, thanks for this sugestion. If i can get better sound that way i am even more happy.
Hello John
>Volume purchases can be done directly with the factory, but that is another story.
Do you have contact details of a good polystyrene capacitor manufacturer in China.
Regards
Arthur
>Volume purchases can be done directly with the factory, but that is another story.
Do you have contact details of a good polystyrene capacitor manufacturer in China.
Regards
Arthur
No, I'm pretty sure they exist, but usually I replace Chinese caps with American or Japanese ones. I know that the replacements are OK.
No, I'm pretty sure they exist, but usually I replace Chinese caps with American or Japanese ones. I know that the replacements are OK.
Hello John
Do you know of any current Japanese companies who supply polystyrene capacitors.
Regards
Arthur
However, the USA has a number of cap manufacturers that are OK with polystyrene, I'm pretty sure. REL is probably still the EASIEST to get paid for samples of, from Michael Percy. Just do it, if you want to know if there is any difference. I usually specify Japanese electrolytic caps, and they are very good, especially Nichicon or Black Gate. Everything else is suspect, for me.
This is what i am building right now. It is a high quality buffer i supply from batteries.
Before the buffer is a 4 position switch and a bypass switch so i can compare 4 pais of caps at a time against "zero". The caps are loaded by a 2Mohm Dale 0.1% metalfilm, nonmagnetic.
The first row shows a 10nF COG-NPO made from 10 x 1nF in parallel, blue 10nF 100V non magnetic Silver Mica, CD 1000V 10nF Silver Mica with steel wires. The second row shows a 10nF 100V Epcos MKT, a 10nF Röderstein 100V MKP 1837 new production in grey case, a 10nF LCR extended foil Polystyrol and a 10nF Styroflex, old style with steel wires of chineese production. The third row has a Mundorf Silver-Oil 1200V polypropylen and a NOS Röderstein KP1832 film and foil 12,2nF 1500V. I will also try to get me 10nF Rifa PPS and REL Polystyrol. I hope i can find some teflons too.
Before the buffer is a 4 position switch and a bypass switch so i can compare 4 pais of caps at a time against "zero". The caps are loaded by a 2Mohm Dale 0.1% metalfilm, nonmagnetic.
The first row shows a 10nF COG-NPO made from 10 x 1nF in parallel, blue 10nF 100V non magnetic Silver Mica, CD 1000V 10nF Silver Mica with steel wires. The second row shows a 10nF 100V Epcos MKT, a 10nF Röderstein 100V MKP 1837 new production in grey case, a 10nF LCR extended foil Polystyrol and a 10nF Styroflex, old style with steel wires of chineese production. The third row has a Mundorf Silver-Oil 1200V polypropylen and a NOS Röderstein KP1832 film and foil 12,2nF 1500V. I will also try to get me 10nF Rifa PPS and REL Polystyrol. I hope i can find some teflons too.
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When it is copper and tin and they are new and not NOS the only company i know of that builds that is LCR in England.
When it is copper and tin and they are new and not NOS the only company i know of that builds that is LCR in England.
They are not new and they were produced in the Czech Republic. Still possible to get them - best caps for freq. compensation.
There is a company in Germany, called Opperman that sells a lot of Styroflex Surplus from Siemens and others, also from the Ex. GDR and East Europe.
I use parts like that for DIY but never for commercial products.
I use parts like that for DIY but never for commercial products.
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