Simplistic NJFET RIAA

Works sweet
i use an old autanator
try with a 10k pot if you have one lying around

Have tested the values when i break in mine 0.3mV cart

10Kohm between earth and line in
4 Kohm betwen line out and earth
13 Kohm between line in and line out

I see. We have the same thing but just a different methods...
I have 1.6mV on mine.
 

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Better twisted pairs. Good luck building.

Hi Salas.

Now I have a few old MM's that sounds all right with the right rod.

Sonus Blue Gold
AKG P8ES Supernova

If you know these old high compliant carts maybe you have it in your head what changes I need to do to get the best out of them. Very good carts both of them - they take control and make you listen instead of writing good posts... :)...

Regards
 
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Hi Salas.

Now I have a few old MM's that sounds all right with the right rod.

Sonus Blue Gold
AKG P8ES Supernova

If you know these old high compliant carts maybe you have it in your head what changes I need to do to get the best out of them. Very good carts both of them - they take control and make you listen instead of writing good posts... :)...

Regards

They just need a ULM arm. Best from the oldies I remember liking was Shure V15 VST-V. Stanton 881s was alright too. The P8ES was more mediocre but competent. Ortofon 2M Black is excellent between the current ones but pricey at ~500 EUR. Can play well on medium mass arms though. MMs are not prone to treble glare due to roll-off which needs good needle & set up in MC to avoid.

If you talk FSP changes you would just need to reconfigure it for 40dB gain based on the guide info. And to load them with just the TT cable capacitance first before try adding Cx loading judiciously.
 
I'm finally up a running. My wife said it best, "that's the best piece of equipment you've ever added to your system". I'm loving the details and wishing I had vinyl instead all these CDs.

I am still confused on one point. Do we want,

a) TP1/TP2 to be as close to 3.6V even if VR2x is cranked all the way
or
b) Leave VR2x somewhat in the middle and live with 3.6V +/- 1V?

Great job Salas and Teabag!!!!
 
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Congratulations. Post some pics if possible.

Leave VR1 in the middle and try for TP1-TP2 ~3.6V with VR2X. Revisit after well warmed up. Engage VR1 only when difficult to set or the rails in the channels end up more than 1V apart.
Cold to hot TP1-TP2 1V travel is normal.
 
Fy faen as we say in Norway........

Replaced the C4 Mudorf ZN 3,3uf for a Clarety Cap MR 3,3uf.

1/2 hrs burn in before testing time.....

Damn its good :)

-The bass is less plump
-The mids is more forward and much more detailed
-the 3D is much better
-and the soundstage is bigger.

An hour or so with music and the sound is getting better and better,

Have some sibilants but i guess the temporary RCAs must take the blame,
Bulletplugs to come

Next possible upgrade is a Clarety MR for C3
 
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I have had a couple of very busy weeks at work, but this weekend I finally finished testing a few things with the FSP and got it in my system. So far it sounds good, but I have only played a couple of LP's. John Coltrane's "Giant Steps" was very nice, very revealing of his amazing tone. A bit of Jimmy Cliff revealed a loose screw in one speaker which was resonating on some very low notes!

However, I had a bit of misfortune, too. I installed my Ortofon MC15 Super Mk II cartridge, balanced the tonearm, aligned the cartridge, removed the stylus guard(*), and re-balanced the tonearm. One "feature" of the Rega RB300 is that you cannot really zero the anti-skate, so the arm swings outward when near balance. As it was swinging I reached for the finger lift with my left hand, and at that instant the tonearm glanced off the rest and bounced straight up. My finger brushed the stylus instead of the finger lift. Good-bye cantilever! :bawling:

I have a back-up LOMC cart, a Sumiko Premiere LMS (spherical tip), so I'm using that. Almost identical output level and impedance to the Ortofon, but I am shattered. In 40 years of doing this stuff (including a few working in hifi shops where I installed dozens of cartridges) I have never broken a cartridge before. I guess I'll see what Ortofon's exchange program is like. I am so disheartened that it is hard to get excited about the Sumiko, but I still have to say that it sounds better than I expected.

Back to the FSP: with my Mezmerize DCB1 at full volume I can hear a bit of hum and hiss near the speakers, but at normal listening levels it's dead quiet (just a hint of hiss if ear next to tweeter). Nothing untoward, and imaging is certainly very good (of course, with independent circuits and power supplies, it should be as good as the phono cartridge can give!). The sound is very clean, no obvious distortion. There may be a hint of sibilance, or it may have been one particular track; I'll give it a while to decide whether I need to trim C2Y. While the unit was on my "bench" (aka dining table) the hum from the raw supply was quite obtrusive, but now that it's on the floor behind the AV stand it's fine.

Time to play more records!

*I would have left the stylus guard in place, but I bought it used and the previous owner appears to have put the guard back on upside-down, so even when "up" it was almost touching the record surface.
 
Hi Salas,

A few pages back there was a comment about using wire-wound resistors for Source resistors (in place of metal films) improved the sound. :confused:

Given that the Source resistor merely sets the current going through the JFET - and is not in the signal path (as there is NFB) - I am curious to know how the type of Source resistor affects the sound.

Are you able to explain? :)


Thanks,

Andy
 
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Hi Salas,

A few pages back there was a comment about using wire-wound resistors for Source resistors (in place of metal films) improved the sound. :confused:

Given that the Source resistor merely sets the current going through the JFET - and is not in the signal path (as there is NFB) - I am curious to know how the type of Source resistor affects the sound.

Are you able to explain? :)


Thanks,

Andy

It moderates the bias & creates local feedback, of course has its tech and materials current noise in addition to its Johnson value. So it plays a little role. I am not sure of how many could pick a difference there from a good metal film but those are the things it does. Wire wound and bulk/Z foil got minimum current noise (any type's residual is exaggerated by more voltage drop so most susceptible is R13).
 
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@ nezbleu

Sorry to know about the cantilever accident. That RB-300 has a spring for the weight dial which is dodgy. In my back up Systemdek IIX 900 which carries one such Rega I saw the aberrant VTF system behavior and I firstly turned the dial full out beyond the 3g mark, then I set the weight with the Shure scale by moving the counterweight only. Without needing to zero balance on air due to having the scale, I just had the magnetic antiskate to minimum. When it was set for VTF I looked for an antiskating that won't carry the needle inwards or outwards on a wide empty track. The HFNRR test record has some locked spaces which I found handy, although they are not there for that purpose. The high modulation bias tracks felt OK after that for channels shared THD near max dB. Else the wand felt resistive to the hand, also unreliable for scale marks, and was changing Vs. the antiskating along the record. Sometimes it would suddenly pull back when I was trying to cue. Luckily it did not lead to an accident before I realized I had to better try the scale with the VTF coil out of the picture.

Anyway, a bummer. Do you like Denon carts? Sometimes there are good prices on DL-103R online, a cart that will never sound unmusical or thin if a bit non refined Vs. expensive ones.
 
It creates local feedback and has its tech and materials current noise in addition to its Johnson value. So it plays a little role. I am not sure of how many could pick a difference there from a good metal film but those are the things it does. Wire wound and bulk/Z foil got minimum current noise (residual is exaggerated by voltage drop in any type of resistor so more susceptible is R13).

Aah, OK - thanks, Salas. :)

Andy
 
Sure, I like Denons. Before I bought the Ortofon I was considering a DL110 high output mc. The 103R is one I would consider. Also, Ortofon have a new line of MC carts coming out, or already out I guess. Maybe there will be some deals on the older ones, or maybe I'll try one of the new ones. Cadenza is out of my league. It's too bad really, I always thought the MC10-15-20-30 series punched above their weight, and i was looking forward to the MC15. Oh well...
 
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Sure, I like Denons. Before I bought the Ortofon I was considering a DL110 high output mc. The 103R is one I would consider. Also, Ortofon have a new line of MC carts coming out, or already out I guess. Maybe there will be some deals on the older ones, or maybe I'll try one of the new ones. Cadenza is out of my league. It's too bad really, I always thought the MC10-15-20-30 series punched above their weight, and i was looking forward to the MC15. Oh well...

Have a look in AT33EV and AT33PTG/II also. EV is tapered duraluminium cantilever & elliptical tip, PTG is boron rod & line contact tip. Bit smoother Vs. bit preciser transcription choice.
Good prices when importing from Japan. Although a step up more expensive than 103R.