Simplistic NJFET RIAA

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Without the follower Zo is almost equal to the last gain stage's drain resistor. You make your decisions from there regarding a specific next stage's input driving ability. In case it sounds weak compare with adding the buffer in JFET types you got. Don't mix types in the follower, this is like a B1 buffer. Needs same and matched. But not super matched like in a DCB1 because its AC coupled so you don't need to super null their mismatch degree resulting DC offset.
 
Hey Folks,

Just about finished with my Simplistic NJFET RIAA phono amp. I going to use the "Clarity Cap 0.1uF 630Vdc, CMR Series for "C3" and the "Clarity Cap 2.2uF 400Vdc, CMR Series for "C4". I am going order them from "Parts ConneXion" .

The 0.1uF is out of stock. As an interim measure I would like to use a cheap Cap. I see lots of people use the "Mundorf EVO Supreme' but they are $40 for two of them. I hate to buy them and then replace them with the Clarity Caps.

Could I use "Solen 0.1uF 630Vdc, SM Series, Polypropylene Film & Tin Foil Capacitor" until I could get some Clarity Caps. How about this one "Obbligato Capacitor 0.1uF 1000Vdc Rose Gold Ultra Premium Film Capacitor".
These are just the two that I found, any other suggestions for a cheap Cap????

Thanks,

Ty

Just to clear up any confusion, I will have the Clarity 2.2uF in place​

 
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Was listening to a big Pass amp at a friend's today. He tried components matching the day before. Found him enthusiastic on how the UFSP and DCG3 are ultra synergistic with this amp's character according to his trials. I wasn't there the other day for more to say but I took a photo today.

System Pass X350.5.jpg
 
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Like many here, I'm using 5 pin XLR plugs for my plugs on the power umbilical. For the female chassis mount jacks, I used Neutrik NC5FD-LX-B. They have a small ground tab, I see how others have done the connections on the cable end, on it's ground plug, but saw no mention of using the one on this female jack.

Reason I ask is, the body of this jack is metal, and there is continuity between it and this small ground tab, so it is effectively grounded to chassis.

Is this in any way a problem, and should I see if they have a 5 pin plug made of that plastic like material they use on some of their other connectors?

Thanks,

Russellc
 

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There is no problem for a two box configuration. The 5th cable (the shield) should be connected into one chassis and we concluded that it's better to the phono chassis.
What is important is to not connect the shield in both ends i.e. chassis to chassis).

So since the 5th cable will go eventually to the chassis I think there is no problem (I assume that this socket is for phono chassis)
 
Was listening to a big Pass amp at a friend's today. He tried components matching the day before. Found him enthusiastic on how the UFSP and DCG3 are ultra synergistic with this amp's character according to his trials. I wasn't there the other day for more to say but I took a photo today.
I think it's the balanced version, right ?
Pass Labs amps working in Greece, brave man your friend and the sarcasm is not directed to him. For everyone else, you will stop winning about gas/electric bill price when you come to Greece, you will suddenly thank your lucky starts that you are a foreigner.
Could not resist. Now back to the thread, i think there is some chance you can bring DCG3 to your liking playing with it's PSU. For FSP changing the capacitors didn't bring so much difference. Maybe it's PSU but I'm guilty of not completing UFSP yet so no first hand experience between the old and the new version.
 
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Thanks. My question is more about the female chassis mount part I showed. Is that ground tab used?

Looks like umbilical shield only soldered to phono board end, not on power supply box.

Seemed odd it had a ground tag on back side, but had continuity to it's metal case. (And thus the chassis)

Russellc
 
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As I understand it. It is only connected at the Power Supply end. Yes, the ground tab on the female chassis mount at the power supply end is connect to Ground. The Male connector that plugs into the Power supply has the shield soldered to the ground tab
the shield is not connected to the ground tab on the male plug on the phone pre box.

I looked at lots of pictures in the thread:cool:

I am finishing my UFSP as well, bout 2 weeks out.
 
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I think it's the balanced version, right ?
Pass Labs amps working in Greece, brave man your friend and the sarcasm is not directed to him. For everyone else, you will stop winning about gas/electric bill price when you come to Greece, you will suddenly thank your lucky starts that you are a foreigner.
Could not resist. Now back to the thread, i think there is some chance you can bring DCG3 to your liking playing with it's PSU. For FSP changing the capacitors didn't bring so much difference. Maybe it's PSU but I'm guilty of not completing UFSP yet so no first hand experience between the old and the new version.
Yes it's the balanced DCG3. Twin boards. Standard DCSTB PSU. Tells me it mates with other gear easily. He tested several sources & amps around it already. So he must have a point.

He liked Nelson's big X amp a lot and he was about to keep it. But it wasn't meant to be. The seller suddenly called it back to be part of a package deal for someone else. Frustrated, but he escaped 500W idle consumption on the other hand.

UFSP proved better than FSP mainly due to the SSLV1.3S. The updated UFSP board design must have contributed too.

That friend has built both versions and the Valve Itch. He loves the valve unit, he spent a lot in rare NOS tubes and Sowter step up transformers. Its delightful and has few dB more gain. But as he moved up the cartridges, power amps, and loudspeakers performance ladder he concluded the UFSP wins in spread and accuracy.
 
@Russelic and @A321Drvr, TeaBags says that he didn't noticed any difference connecting the 5th cable to either sides.
@A321Drvr, I've connected my 5th cable the other way, to the Phono chassis/ground, while you say you have it on the PSU ground/chassis. The important is to NOT connect it in both side and of course if you don't connect it anywhere is useless.

@Salas. great info. I think I better do an A/B with the old and new regs.
Yes I agree for top circuits the job is to have the best synergy, you are individuals and have our own taste.
I set aside Magnepans and testing box speakers and I'd love to hear how UFSP/FSP perform with them.
I won't be surprised if it turns out to be chameleon. and anyway I've kept it so many years aside my Audionet PAM and that's says it all.
 
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As I have listened to his system, key aid in his choices is the increased midrange resolution and presence of the ATC monitor speakers. There's an SVS closed box sub in a corner too. He started to discriminate gear more apparently for their pros & cons with the ATC.
 
By the way, turntable is Bauer Audio DPS3 with the Bauer unipivot tonearm, cartridge is Dynavector DRT XV-1t.
It's a great setup for any demanding listener. I don't figure out the speakers, SCM19 ?

He liked Nelson's big X amp a lot and he was about to keep it
I guess the XAs Class A monos. I heard they have different character than their Xs Class AB amps, having more texture and staging, maybe better match with FSP ?