A question regarding Ono

[giolight]

I have made the Ono and it has been for me a really interesting experience about components choice, in this case caps. I have mono power supply and I used r-core trans.I started with polycarbonate 10uF caps, Ero 1810 , and micas in the rria network. My previous phono was tubes kind and at first the Ono seemed a big improvment with incredible tight and rich bass really impressive but after a while I recognized a disturbing mid-high and high sandy effect. I just remembered those story about ss sound. I took away the Ero from signal circuit, it was just one 10uf capacitor since I used PD tips for the output cap, and I switched to polypropilene Arcotronics, the kind used with motors as suggested from some big head. I was again shocked at how much difference one single cap can make in such a complicate system as mine , active xo quadriamped horns. It was mellower than my previous phono valve and the bass just hanging around without control. So I decided to take a new step because I was feeling the circuit potential I thought it was a matter of tuning. I bought Rel cap PPMX the 10uf and rtx in the rria.
I have spent quite a lot but I must admit they are completly another class from my previous caps.
Now I have sold the tube one and I really enjoy the Ono fantastic resolution and sound, control deep of stage and grain free are the most distinguished characters.

[jcarr]

Peter:

>What would you recommend for the RIAA caps to start with?<

The RIAA caps that I normally use are teflons in hermetic packaging. US manufacturers include CRC (Component Research Corporation) and Hi-Rel Capacitors. I haven't tried the Russian teflons yet.

>Some people claim that silver mica is best for that, but I don't believe it.<

I've used silver mica in the past, and some of the older Connoisseurs contained these, but today I stay as far away from them as I can. Certainly they sound very, very different from the teflons. Subjectively they appear to add a treble "spice" that can help juice up a system of low resolution, but I find this quality obnoxious on more neutral-sounding systems. They also add a sort of sparkling grain to the sound, like someone was sprinkling fine metallic powder into the soundstage.

>MIT RTX.<

I think that we did RTXs for some of the "Crosby" modded Spectral DMC-10Z preamps, while other DMC-10Zs got the PPFXs. As you say, the RTX is a rather large part. After we established that the Teflons sounded better, I didn't try to go back and establish a precise hierarchy for the RTX nor PPFX. I sometimes use the MITs in DC servo applications, but don't have any particular emotions regarding them, either for or against. I don't think that these are too bad, but they definitely can be improved on.

I agree that knowing of an affordable, compact RIAA cap of high-quality would certainly be useful!

regards, jonathan carr

[roddyama]

Originally posted by jcarr
Peter:

...>Some people claim that silver mica is best for that, but I don't believe it.<

I've used silver mica in the past, and some of the older Connoisseurs contained these, but today I stay as far away from them as I can. Certainly they sound very, very different from the teflons. Subjectively they appear to add a treble "spice" that can help juice up a system of low resolution, but I find this quality obnoxious on more neutral-sounding systems. They also add a sort of sparkling grain to the sound, like someone was sprinkling fine metallic powder into the soundstage...

regards, jonathan carr

Hi Jonathan,

What about the polysyrenes?

[Peter Daniel]

Originally posted by jcarr
They also add a sort of sparkling grain to the sound, like someone was sprinkling fine metallic powder into the soundstage.

I like that description, and this is what I noticed too

I sometimes use the MITs in DC servo applications, but don't have any particular emotions regarding them, either for or against. I don't think that these are too bad, but they definitely can be improved on.

I have a similar view on MIT. While pretty neutral somehow they don't sound completely natuaral. I tried bypassing them with silver foil caps, but although it seemed to be better in the beginning, in a long run proved even worse.

I'm recently very content with Siemens MKV caps and so far I found them to sound most natural, especially in trebles. But again, they are pretty large.

[jewilson]

Peter,

The Teflon CRC caps are very good they have the best DA of all caps I've tested. We used these caps in high speed sample and hold circuits because of the DA and there low leakage. Also, I have found that they are great in a phono RIAA filter.

Telfon circuits board are very close mounting the components in air. If your using high impedance parts the PCB can effect the circuits performance Teflon is superior here. Also, PCBs can have lots of distributed capacitance which can make thing worst just as a poor solder mask can. The Teflon PCBs are a pain to work on, the traces don't hold, but they are great for high temp and high impedances.

[Peter Daniel]

Originally posted by jewilson
The Teflon CRC caps are very good they have the best DA of all caps I've tested. We used these caps in high speed sample and hold circuits because of the DA and there low leakage. Also, I have found that they are great in a phono RIAA filter.

Where are you get them from?

[jewilson]

http://www.crcfilm.com/welcome.htm check them out.

Also, I still have a bunch around.

[thoriated]

Wish I knew who made teflon films under 1000 pF, though.

[GaryB]

www.crcfilm.com/welcome.htm - check them out.

Will they sell in small quantities to the DIYer or do you have to buy a minimum quantity. And any idea of the ballpark price?


---Gary

[Panelhead]

The company I used to work for used these in high temp well logging equipment. The application became outdated when the instruments went from analog to digital.
These are still available surplus around Houston for a dollar or two each. John Tucker of Exemeplar had a box full when he lived here I sold a bucket full to someone for 200.00 couple of years back.
But one warning, they have steel leads. They were welded to the circuit boards.
I used to stuff these in everything. But I think they are far from neutral.
A lot of the surplus caps had H numbers printed on them. These were the stocking numbers at my previous employer. Most were Custom Cap or TexCap branded, but may have been made by CRC.
If they now make them with copper leads these would be awsome. But the model shown on the website are far from state of the art sonically. They were made to work in a 600 degree environment, not offer special electrical characteristics.

George