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Old 25th December 2008, 09:04 AM   #551
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OK I did the mods you guys mentioned- thanks. Q4 fet in shunt much cooler now- just warm to the touch.

I lowered the Rload to 180 ohms and changed the 2 82k's to one 43k. Base has improved; still not quite like the SUT hook up; but better.

What I am hearing is more articulate base. The SUT 'seems' to have slightly more cohesion- or it could be that the jfet RIAA is separating the instruments out better...! I need to do more listening, probably after xmas passes. I will also try it with a buffer. Sadly many of my old fave records have a lot of sibilance- comes from being played at a college radio station TT with 5 gram carts!
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Old 25th December 2008, 09:41 AM   #552
AndrewT is offline AndrewT  Scotland
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Salas,
what difference does changing 82k//82k up to 43k make?
@20Hz how many dB? or is it ~tenths of a dB?
Just what level of bass adjustment has Kst heard?
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Old 25th December 2008, 09:56 AM   #553
Salas is offline Salas  Greece
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Merry Christmas Andrew! For Kent's RIAA changes see posts #496,497 page #20. He was off a bit from what I have tuned due to practical tolerances with his capacitors. Also he damped differently and more properly his MC cart now. This is hands on stuff Andrew. The analogue rigs can learn you their points of interest only if you mess enough with them, difficult to predict only by proper electronics design. He will still be impressed more when he will substitute his 43K with Shinko or AB resistors. Its bugging for planing but those things do matter in the end. He will also need a buffer. And that simple 150% Idss one proved transparent to Jonners. But I have given a B1 type earlier too. Also sibilance, is tell tale not only of worn out records, but also of something slightly wrong with geometry. Maybe 2 degrees of nose up VTA adjustment and protractor check can yield impressive results. This phono really shows.
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Old 27th December 2008, 07:13 PM   #554
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for tonearm ground better put a caps in series?
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Old 28th December 2008, 01:07 PM   #555
Salas is offline Salas  Greece
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Not really. Why just AC couple the tonearm ground? Having a low noise floor FFT measurement set up can show the course of such grounding experiments if there is a specific loop to solve. In general it is not needed to mess too much with the metal parts grounding of a TT.
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Old 28th December 2008, 02:50 PM   #556
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the arm ground was not connect in this past 6month, no problem but this days I dont now why, when I touch the arm lifter there is a soft hum from speakers ......

all connector look ok
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Old 28th December 2008, 03:23 PM   #557
Salas is offline Salas  Greece
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See if your arm tube has continuity all the way to the ground post on your phono with a multimeter. Maybe your fifth (grounding) wire has lost continuity?
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Old 28th December 2008, 03:44 PM   #558
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good suggestion Salas ,all are dual mono , arm wire broke the isolation and touch the arm..? I will try ,better disconnect the cartridge ....if I do I need change the pin for new and the cartridge screws are not so tight.....
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Old 29th December 2008, 05:36 PM   #559
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Default Charge-transfer circuit

http://www.diyaudio.com/forums/showt...97#post1675297

Salas look good....


http://www.diyaudio.com/forums/attac...amp=1229076984
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Old 29th December 2008, 08:10 PM   #560
RCruz is offline RCruz  Switzerland
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Quote:
Originally posted by nicoch46
I play with Rload , 3k close to much the sound , usally I like 23k , but in my system i think 8-15k range are optimal
(a switch // r for two setting, soft or racing )


Pacific+ dl160+P3 compete with last Pedja dac.....not so bad!!!

Quote:
Originally posted by salas
The Denon has 160 Ohm Zout, so 1.5k upwards is fully testable for system tonal matching.
I know I am late and did not build the Salas RIAA "yet" but I am already preparing the "stage". The new RIAA wil be used on my RD80 + Maggeddon + Benz ACE M.

In also want to keep my actual pre so I recently revived a JVC belt drive and installed a DL160... It is a really powerfull cart but I would like to tame its high freq response. (In my MM riaa, the load is 47k and the highs are too forward)

How low (in value) can I set the load resistor ?

I would not like to loose any of the thunderous bass the DL160 is providing

Regards

Ricardo
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