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Old 20th August 2011, 07:37 PM   #6701
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Pearfarmer

Ittok have the same effective mass than Ekos so medium mass, I use my Lp 12 + Ekos + Denon DL103R nude adding a little of mass with oustanding success married with Salas RIAA 58dBs.

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Old 21st August 2011, 09:50 PM   #6702
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Default line preamp

Thanks, Salas and Merlin.

I had seen a post in the F5 power amplifier thread which states the the F5 does not need a preamp, depending on the input. Is the problem that there really isn't a defined standard output range from phono stage, line stage power stage, etc.?

I just did a calculation, and it looks like the F5 needs 2.43Vrms input for 25W output into 8 Ohms. Perhaps the F5 does not need a preamp when using a high output DAC or CD player.

At any rate I am looking at building the Pumpkin preamp, because I do like some volume occasionally.

Also, Thanks, Salas for pointing out the hyperlink in thread number 1. I had missed this before. I'll post my FET values soon, so that I can get started.

Andy
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Old 21st August 2011, 10:12 PM   #6703
Salas is offline Salas  Greece
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60dB to 63dB is what is used by majority for Low MC and keeping hiss and internal transient over load at bay. That leads to 250-350mV RMS from a 0.25mV cart. Records do have modulations to track near enough some CD recordings for same volume position and ~300mV 0dB phono, mind you. Especially with 45RPM wide dynamic records. Its either you will make the pre-pre and HOMC combo from the PDF for 63dB but one more stage, or I can recommend you a quad K170 60dB gain one. With the Pumpkin it will suffice.
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Old 24th August 2011, 10:40 PM   #6704
orelli is offline orelli  Italy
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Default Simplistic JFET RIAA balanced

Hi all, none thinked to a balanced version? Of course interesting only MC users.
Balanced items are always more dinamic, open soundstage and more silent (best
CMMR),but ... never simpler.
Any suggest?

Best
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Old 24th August 2011, 11:34 PM   #6705
Salas is offline Salas  Greece
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Merlin did once!
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Old 25th August 2011, 12:59 AM   #6706
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Quote:
Originally Posted by orelli View Post
Hi all, none thinked to a balanced version? Of course interesting only MC users.
May I ask why balanced phono pres would only be interesting to moving-coil cartridge users? A moving-magnet cart still has a coil to generate the signal... can this not be wired in balanced configuration with all of the CMRR benefits that come with?
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Old 25th August 2011, 11:51 AM   #6707
orelli is offline orelli  Italy
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sincerly , I don't know

@ merlin
how do sound the bal version? It' s worthy of the extra work?
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Old 25th August 2011, 12:25 PM   #6708
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Quote:
Originally Posted by orelli View Post
sincerly , I don't know

@ merlin
how do sound the bal version? It' s worthy of the extra work?
All depends if the rest of your gear is full balanced or not?
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Old 25th August 2011, 12:26 PM   #6709
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Quote:
Originally Posted by taniknight View Post
May I ask why balanced phono pres would only be interesting to moving-coil cartridge users? A moving-magnet cart still has a coil to generate the signal... can this not be wired in balanced configuration with all of the CMRR benefits that come with?
MM users also can do balanced, as MC all depends rest of stuf if it's balanced or not.
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Old 25th August 2011, 04:49 PM   #6710
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Hi all,

I finally had the parts arrive to enable me to start my phono. I'm using 60dB gain version with 45V supply and 8.5-8.7mA Jfets.

I've tried initially with a 36V supply from a Salas shunt, the LEDs initially light up but then dim and go off after a couple of seconds. I get no sound/hum and nothing is getting hot. Any ideas please?
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