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Old 16th January 2009, 05:41 PM   #661
iko is offline iko  Canada
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Oh yeah, thanks salas, I'm totally psyched up now.

Hey, Rcruz, point to point can be quite easy if you strip a thin wire and solder the parts along it, if they belong to the same network branch. I'm not in the mood to etch a board so I'm pretty sure I'll use some of the fine silver wire I got cheap from fleabay and I'll probably stay with ptp. Nothing wrong there.

jonners, can't wait to hear more about the sonics.
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Old 16th January 2009, 07:51 PM   #662
RCruz is offline RCruz  Switzerland
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Quote:
Originally posted by jonners
Teflons - 2 in parallel for series RIAA caps.

Quote:
Originally posted by salas


What a coincidence! I just came back with a couple of those! I want to try them for inter stage coupling in the RIAA. You are appointed as the official burn in authority and sonic compatibility reporter before I remove the CCCP Polysterenes and try those. Please let me know if I must do the operation doc!
The pictured caps indicate different values...

In the schematic C1 = 100nF, in the first case we will have 116nF and in the second a little less then 100. Does it mean we can modify C1 value ?
What should be the effect ?

Ricardo
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Old 16th January 2009, 08:11 PM   #663
Salas is online now Salas  Greece
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With 100nF the roll off is nicely low. The phase won't twist that early.
In case there is a superior capacitor to try, I would advise no less than 33nF for a little less than 10Hz turn. Essentially the same question has been discussed also in posts #597,599. Jonners can tell us if there is any subjective impact, negative or positive, if he will disconnect one 56nF.
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Old 16th January 2009, 08:35 PM   #664
RCruz is offline RCruz  Switzerland
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Thank you Salas

So it is a coupling cap.

I did not know if it would modify the RIAA curve.
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Old 17th January 2009, 01:47 PM   #665
jonners is offline jonners  United Kingdom
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Quote:
Originally posted by salas
With 100nF the roll off is nicely low. The phase won't twist that early.
In case there is a superior capacitor to try, I would advise no less than 33nF for a little less than 10Hz turn. Essentially the same question has been discussed also in posts #597,599. Jonners can tell us if there is any subjective impact, negative or positive, if he will disconnect one 56nF.

Minor cap-ectomy operation was performed as proposed. No audible or measurable loss of bass as a result. Conclusion: Patient is happy and healthy with just 56nF in series.

Dr Jonners
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Old 17th January 2009, 03:19 PM   #666
Salas is online now Salas  Greece
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Expected medical theory result confirmed by field surgeon.
56nF does safely low for frequency and phase turn in our 1MegOhm second stage load. 56nf turn the phase only by 8deg @ 20Hz. 33nF by 14deg. Both acceptable but 56nF is more correct. If anyone is buying, better look for the 56nF. Also the K71-7 120nF green PP metalized foil and Polysterene separator CCCP military cap that I already use is really good, amongst best metalized caps but cheap. Going to upgrade for K72P-6 too. This film and foil Teflon is even better.

Regards.
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Old 18th January 2009, 03:39 PM   #667
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Default mods

I have some idea to rebuld the AC cable...

for now I have mod one mains distribution blocks ,were are the phono and TT motor

delete the cheap emi filter
delete the cheap thermal brake ,better than fuse but ring ......
add new 0.47mf X2- murata diff/Comm Mode coke-0,1mf X2 for phono

unfiltred for motor

after the stealt mod my test sibilance LP sound a little pronunciate now are ok

can I put this Emi for motor ? (are in my previous amp )
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Old 18th January 2009, 08:19 PM   #668
Salas is online now Salas  Greece
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I know that it can help amplifiers, I am not sure for motors. I know that isolation transformers help AC motors by experience. You must try and tell us. Best such circuits use common mode choke though.
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Old 18th January 2009, 11:09 PM   #669
RCruz is offline RCruz  Switzerland
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I was waiting for this oportunity for some time now!

"Filter the motor psu with a common choke."

Hope it works as it is very easy to implement.

My 500VA toroid "Maggeddon" is direcly fed from the mains and feeds 110v (initially220v) to the motor.

Very rewarding as is but I would like to know if filtering the motor psu should bring more noticeable benefits.

PS: Cart loading tests:
After using 464r, 1k 27k and after combining 27k with 4700pf 3300pf 560pf 330pf 120pf and no cap on the cart load, I finally settled on 37k without cap for loading the Benz M. Maybe it likes 47k after all.

VTA is so evident right now ... unbelieavable... (must decide between 15 or 16 cards height )

Ricardo
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Old 19th January 2009, 12:26 AM   #670
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the filter idea are only for isolate better amp/phono to motor and 220v wire from pick up rfi ....

but yes can helps the motor , side effect



Jon Risch emi filter

link
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