Simplistic NJFET RIAA

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Precisely my problem. Pearl 2 is @ 55 dB. And it's rather low with DCB1, TSSA and 89.5 dB speakers. On the longer run I plan FS which can provide extra gain. Would SH be even worse then respectively?

SH should be the bit worse one normally bcs of more coil turns. But I have no specific info on it maybe they have tackled it very well. Better ask them their opinion. Big output can overload phono stages or at least increase their THD noticeably when you plan to keep the same gain setting.
 
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Hi Salas,

Thank you for your support.

Your questions put me on the track! A rookie mistake, I am ashamed for telling you the truth.

Well, it is working like a charm.

It needs now a beautiful case, because (sorry for the quality of the pict):
An externally hosted image should be here but it was not working when we last tested it.

Congratulations. What are the pre-regulation boards? Have you listened to it carefully yet, and for what cartridge is it made for?
 
Congratulations. What are the pre-regulation boards? Have you listened to it carefully yet, and for what cartridge is it made for?

The pre-regulation boards are the SR50 Variable Shunt Regulator from analog metric. But I do not recommend them they run too hot. So I use them only as bridge rectifier and cap filter. I plan to improve this part before the final implementation.

My cartridge is an Ortofon 2M red.

I did not listened to them carefully yet.

I had previously the "Aikido Phono Riaa" (Aikido Phono Riaa Verstärker für DIY Projekte. FET Phono Fertig u geprüft. | eBay).

As a quick comparison, the simplistic NJFET RIAA has a bit less bass. But the medium and high are much better defined.

I will also try to play a bit the C4, i am using today a simple Mundorf Mcap, and would like to try something more fancy.

Thanks again for your support.
 
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SH should be the bit worse one normally bcs of more coil turns. But I have no specific info on it maybe they have tackled it very well. Better ask them their opinion. Big output can overload phono stages or at least increase their THD noticeably when you plan to keep the same gain setting.

Just asked Benz guys about their opinion. I can up the gain to 65 dB on my phono, but that still leaves me guessing. Will there be enough gain with a 0.4mV cartridge in my whole chain dynamics wise.

I can also get the Glider SM for 100 eur extra. But that doesn't look worth it or feasible for me at the moment.
 
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The pre-regulation boards are the SR50 Variable Shunt Regulator from analog metric. But I do not recommend them they run too hot. So I use them only as bridge rectifier and cap filter. I plan to improve this part before the final implementation.

My cartridge is an Ortofon 2M red.

I did not listened to them carefully yet.

I had previously the "Aikido Phono Riaa" (Aikido Phono Riaa Verstärker für DIY Projekte. FET Phono Fertig u geprüft. | eBay).

As a quick comparison, the simplistic NJFET RIAA has a bit less bass. But the medium and high are much better defined.

I will also try to play a bit the C4, i am using today a simple Mundorf Mcap, and would like to try something more fancy.

Thanks again for your support.
Riaa curves may differ between phonos, coupling caps values can influence also (here we go for almost flat) so for tonality some could be bit bassy, bit toppy. Since the definition is higher that is good news. VTA can influence the tonality if you can play with the arm easily on that aspect. The treble trim cap can help also of course.
I am at Vgeorge's place now, visiting for a couple of days, tonal consistency of the FSP seems spot on with his AT ART9 on SME IV. Big four way half active horn system with 15 inch subs hides no spectral weaknesses if there.
 
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Just asked Benz guys about their opinion. I can up the gain to 65 dB on my phono, but that still leaves me guessing. Will there be enough gain with a 0.4mV cartridge in my whole chain dynamics wise.

I can also get the Glider SM for 100 eur extra. But that doesn't look worth it or feasible for me at the moment.

You could calculate the output level and then apply test signals or pad down your CDP at that expected level and pre-evaluate. George has a Subbu 3 DAC and 63dB on his cart. Its a 0.5mV cart at 47k spec. On normal 180 Ohm load it should be about 0.4mV. He switched from Subbu to phono at a point and there was no change in level, maybe the TT was bit stronger if anything.
 
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Yes, RMS, you are right.
Any tests, useful observations, shootouts, conclusions, impressions after visiting Rhodes and that spectacular system of George?

Its Poros relatively near to Athens, Rhodes is far away in the South East Aegean and much bigger, has a medieval knights castle even.

George had done a lot of work since last time I visited. Had added the DBX Driverack PX controller, the IR class D amp, and the smaller sealed cubes for the 15 inch Lambdas instead of the enormous triple reflex boxes he had. That's the new gear for the bass route. He had also added the 6V6 cathode follower preamp with SSHV2s instead of the #26, the SME IV arm with the AT-ART9 cart on the VPI Aries plus the Falcon AC motor PSU with Roadrunner hall effect tachometer controller, and a nice rubberized cork black mat. He had moved the TSSA amp in a bigger box with populous rows of PSU filter caps. On the digital side he had added the Subbu 3 on Reflektor-D at 400mA 5V PSU fed by a Shigaclone transport. Some ceiling and back wall absorber frames, more side walls media storage selves providing some scattering were new also.

Basically the system was working well without noises or problems. On first listen I found it somewhat misaligned in the HF though, I was remembering the Fostex bullet supertweeters better integrated and the midbass more fleshed out since we last implemented the crossover. The answer was that the right hand side one had been moved forward unconsciously during some dusting maybe, we restored that. We also bypassed series resistors to the double 12 inchers semi horn boxes that were good on the fat power range Shelter 901 but no longer needed with the neutral ART9. The HF Z alignment to the Great Plains drivers on Azurahorns and the lower mid crossover got reset to original in other words.

Comparing to the older visit the sound was obviously better controlled in room for bass and reverberation (DBX provides EQ bands also, was running a 100HZ 24dB Butterworth low pass we confirmed preferable in this blend). The rest of the spectrum was cleaner, wider, deeper, more informative, majestic. Sense of pitch and rhythm was feeling more defined. With very good cuts on the platter the big stage and low distortion dynamics in wide bandwidth created a persuasive enough musical event. The digital route was almost same spectral tone but was lacking in liveliness vs the TT, good in flow and not fatiguing, but less exciting by a good margin. Better than his older SONY CD player though, not as dark.

We also tested a Krell KAV-300iL in place of the TSSA from 100Hz up after we leveled the gains in the DBX but it was below par, the tone loosened and lost enough naturalness vs the CFA class A diy amp, the HF got lost in space for focus when some mid forwardness and a stage flattening was apparent, he will relegate it to TV audio duty in the living room.
 
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TSSA vs Krell. DIY pwns:)

Its a very specific task where the power advantage plays no role and the DIY amp shines. They got better amps that can control difficult inefficient speakers, this small (by their standards) integrated can do that well enough also, but tone its not its best attribute. In such a system at least. George no longer needed the McCormack power amp for the subs and he did well to swap it for use in the living room since the KAV has remote controlled integrated facilities and 200W power to go on its own in a slim well made box.
 
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When summed up, George has made quite some improvements to his system. He's a steady developer. It's not a race, but I feel slow in comparison.

Indeed. Now it feels much developed. He surely has some bug for the next creative season already though since the "what you miss in the speakers" questions were more than suspicious.:D
 
I feel slow in comparison.

I have putted my blue pcb's on a piece of paper, aligning the physical design in the box:)

Well I have worked over a month with some adjustable passive xovers. And now I ripped out my workbench and started installing a monster with built in multi psu's, everything screened, mains ripple filtered etc. Puh.

Well one DIY enjoyment is to suck the caramell as long as possible. I'm good at that:)