Pass Pearl PCBs and related parts

[luvdunhill]

Great work Marc! I have a few observations/questions.

What unregulated psu clamps/cap are you referring to (the 10k uf caps?? Aren't those mounted on the pcb?). How would using the stock 10k and 3.3kuf caps be cutting corners? Is there evidence that more capacitance is needed here/beneficial... based on rules of thumb, or precedent from other similar projects? Any downsides to putting in bigger psu filter caps?

the first thing on the PCB is a series resistor. So, you'll need either 1 cap off board, or remove this resistor and use the first cap on the board as your first smoothing cap. There is a separate schematic in the service manual that shows this.

More or less capacitance is not an argument I'd like to have. I did double the capacitance in my Xono clone and it had a positive effect. Not as much as tweaking the RIAA circuit or even bypasses on the main board. Downsides would be more inrush current to deal with, and some people think that things don't sound as "quick"... YMMV, but there are 2 options and feel free to go either way. If you want something else (like the 2" tall stuff) just send me part numbers.

Can we include a nice power indicator led or two? Blue or violet color

sure, I can throw some in, or pick from Digikey. I'd place it and the necessary resistance after the first cap on each psu.

Three values of loading resistors/caps (at least the most popular ones 1k, 47k, other? 0pf, 100pf, other?) along with selector switch(es) for that purpose? Could be done manually in the box if necessary. Just a thought.

sure thing! You can do things Manley style, have at it I use dip switch box (for lack of a better term) on my Xono which works well, but in my case you have to open up the enclosure. Using selector switches would be pretty nifty.

Is the diode bridge a soft recovery type? Can it be? Does it matter?

no, I chose this bridge because it's easy to mount and has fast-on tabs. If you want to go with individual diodes like the CREE zero-recovery Schottky, or Fairchild Stealth, do it... they don't need to be heat sinked, but you'll have to build out a little PCB for them to sit on.

Will any of the 1.5" tall heatsinks fit/work? Trying to fit into a 2" tall case, if feasible. Same comment for the large caps.

Cheers

Pete

I don't see why not, but you may need to add some holes in the top and not stack the boards. Feel free to shoot me any part numbers you're interested in and I'll add them to the list!

[luvdunhill]

This leaves the JFETs, coupling capacitors, capacitor clamps for unregulated PSU cap, RCA jacks, earth binding post, and resistors.

So $153.50 for your recommendations for this part of the order? Would this complete the parts needed?

no I can only do so much my friend. I don't think we could have gone cheaper on the case or toroids. Just choose the simpler PSU version option and I'll continue to try and hit your cost target.

[grawk]

ok, so 116.50

[luvdunhill]

PMs sent out for Digikey parts.

[luvdunhill]

PartsConnexion part list:

RCA jacks			(2)	CONNEX-68140

earth post			(1)	VAMPIRE-55449

capacitor clamps		(2)	CLAMPS-58847

coupling caps              (2)	MUNDORF-71340


R1				(1*2)	<user value>

R10				(1*2)	PRP-50038  	22K    	0.25 Watt

R12				(1*2)	PRP-50026  	4K7	0.25 Watt

R13				(1*2)	PRP-54542  	1K5	0.25 Watt

R14				(1*2)	PRP-70167  	1K0   	0.25 Watt

R15				(1*2)	PRP-50051  	100K 	0.25 Watt

R27				(1*2)	PRP-50045	47K	0.25 Watt

R28-R31				(4*2)	PRP-50001	22R	0.25 Watt

R4,9				(2*2)	PRP-70165	221	0.25 Watt

R5				(1*2)	PRP-53818	3K3	0.25 Watt

R6,R7,R11,R16,R17,R18,R20,R21	(8*2)	PRP-50032	10K	0.25 Watt

R8,R25				(2*2)	PRP-50000	10R	0.25 watt

I think this could be considered a minimal list. Cost including a few dollars shipping for each individual is $3 (shipping to me) + $16.80 (resistors) + $17.30 (capacitors) + $25.25 (jacks) = $62.35 * 1.03 (PayPal) ~= $65.

** Don't send me any money yet, as I'm waiting to see what goes on sale at PartsConnexion on the 1st and we will see if we can save a bit more. **

I also have some Russian teflon bypasses to throw in as well. Parties interested in other coupling capacitors, contact me.

All that remains is the 2sk170BL / 2sk389BL. I'm considering just offering a matching service and giving you 2 matched pairs and 2 matched quads of the Linear devices, or 2 of the can LSK389 and you can play lead twister. I can either sell the new Linear devices to you (I'd probably recommend getting 20 or so) or you can buy matched Toshiba devices from Jack (see somewhere in the thread). I should also have some matched Toshiba devices if you wanted to get them from me, but I'm going to charge about the same he does (minus shipping of course). Matching the quad is not necessary, but should improve noise and if you wanted to lower the ballast resistors you probably could get away with it.

What does the peanut gallery say?

Sorry if my initial estimate wasn't spot on. I tried my best. If you'd like to source these parts yourself, feel free. No pressure, just trying to make things easier for people.

[swt61]

^^^

This peanut says that I'll get you to explain it better to me this weekend.

Honestly I do much better when I just get a bill that says "this is what you need, and this is what you need to pay".

Will the diodes be pretty and color coordinated?

[DigiPete]

PartsConnexion part list:

RCA jacks            (2)    CONNEX-68140

earth post            (1)    VAMPIRE-55449

capacitor clamps        (2)    CLAMPS-58847

coupling caps              (2)    MUNDORF-71340


R1                (1*2)    <user value>

R10                (1*2)    PRP-50038      22K        0.25 Watt

R12                (1*2)    PRP-50026      4K7    0.25 Watt

R13                (1*2)    PRP-54542      1K5    0.25 Watt

R14                (1*2)    PRP-70167      1K0       0.25 Watt

R15                (1*2)    PRP-50051      100K     0.25 Watt

R27                (1*2)    PRP-50045    47K    0.25 Watt

R28-R31                (4*2)    PRP-50001    22R    0.25 Watt

R4,9                (2*2)    PRP-70165    221    0.25 Watt

R5                (1*2)    PRP-53818    3K3    0.25 Watt

R6,R7,R11,R16,R17,R18,R20,R21    (8*2)    PRP-50032    10K    0.25 Watt

R8,R25                (2*2)    PRP-50000    10R    0.25 watt

I think this could be considered a minimal list. Cost including a few dollars shipping for each individual is $3 (shipping to me) + $16.80 (resistors) + $17.30 (capacitors) + $25.25 (jacks) = $62.35 * 1.03 (PayPal) ~= $65.

** Don't send me any money yet, as I'm waiting to see what goes on sale at PartsConnexion on the 1st and we will see if we can save a bit more. **

I also have some Russian teflon bypasses to throw in as well. Parties interested in other coupling capacitors, contact me.

All that remains is the 2sk170BL / 2sk389BL. I'm considering just offering a matching service and giving you 2 matched pairs and 2 matched quads of the Linear devices, or 2 of the can LSK389 and you can play lead twister. I can either sell the new Linear devices to you (I'd probably recommend getting 20 or so) or you can buy matched Toshiba devices from Jack (see somewhere in the thread). I should also have some matched Toshiba devices if you wanted to get them from me, but I'm going to charge about the same he does (minus shipping of course). Matching the quad is not necessary, but should improve noise and if you wanted to lower the ballast resistors you probably could get away with it.

What does the peanut gallery say?

Sorry if my initial estimate wasn't spot on. I tried my best. If you'd like to source these parts yourself, feel free. No pressure, just trying to make things easier for people.

Looks good. For R1 how about 47k and 1k? For coupling caps I would like Auricap-62341 10.0uf 200v (unless there is a better cap at the $25ish price point, open to ideas here).

Matched pairs and matched quad service would be much appreciated.

Cheers

Pete

[luvdunhill]

For R1 how about 47k and 1k?

good idea. I'll add those.

[luvdunhill]

Looks good. For R1 how about 47k and 1k? For coupling caps I would like Auricap-62341 10.0uf 200v (unless there is a better cap at the $25ish price point, open to ideas here).

this is really a taste issue. I find that bypassing the reasonably priced Mundorf M-Cap (or perhaps even better, the biggie box caps like Rifa PHE450 (yum) or Wima MKP4 / MKP10) with something nice is a reasonable option here, hence my default recommendation of the M-Cap with Russian teflon bypass. Depending on the Zin of your preamp / headamp, you can go with something lower than 10uF as well, so keep that in mind.

I've also used Black Gate N (flame away for using a electrolytic as a coupling cap) with good results.

The Auricaps are a good recommendation, as are Multicaps, or the Zen capacitors from North Creek's going-out-of-business sale.

Outside of the above recommendations, I don't have much to offer

[DigiPete]

this is really a taste issue. I find that bypassing the reasonably priced Mundorf M-Cap (or perhaps even better, the biggie box caps like Rifa PHE450 (yum) or Wima MKP4 / MKP10) with something nice is a reasonable option here, hence my default recommendation of the M-Cap with Russian teflon bypass. Depending on the Zin of your preamp / headamp, you can go with something lower than 10uF as well, so keep that in mind.

I've also used Black Gate N (flame away for using a electrolytic as a coupling cap) with good results.

The Auricaps are a good recommendation, as are Multicaps, or the Zen capacitors from North Creek's going-out-of-business sale.

Outside of the above recommendations, I don't have much to offer

Ok, I'll stick with the M-cap and teflon bypass. I could always pickup another cap later if I really get the itch

For my PSU caps please use P6692-ND x8 and P11249-ND x8

For heat sink I'll use HS-131-ND.

Also thinking... should we include diode snubber caps?

Can we include 100pf silver mica (or whatever is very good here, and whatever is a common value for input loading caps) for extra input load caps?

That should do it.

Cheers

Pete

[luvdunhill]

Ok, I'll stick with the M-cap and teflon bypass. I could always pickup another cap later if I really get the itch

For my PSU caps please use P6692-ND x8 and P11249-ND x8

For heat sink I'll use HS-131-ND.

Also thinking... we should included diode snubber caps?

Can we include 100pf silver mica (or whatever is very good here, and whatever is a common option for input loading caps) for extra input load caps?

That should do it.

Cheers

Pete

Thanks Pete. I use around 150 ohms for my LOMC cartridge. A maximal set of values would be something like:

47, 100, 470, 1k, 10k and 47kΩ

0, 100, 270pF, 370pF and 470 pF

Perhaps you can check around and see what other phono stages use?

For the type, either mica, or the same Panasonic ECQP(Z) caps would be fine. What do you prefer?

If you want some snubbers, I can do that. I usually use BC Mono-Kap and probably have a strip laying around somewhere I can include if that's okay with you.

[DigiPete]

Thanks Pete. I use around 150 ohms for my LOMC cartridge. A maximal set of values would be something like:

47, 100, 470, 1k, 10k and 47kΩ

0, 100, 270pF, 370pF and 470 pF

Perhaps you can check around and see what other phono stages use?

For the type, either mica, or the same Panasonic ECQP(Z) caps would be fine. What do you prefer?

If you want some snubbers, I can do that. I usually use BC Mono-Kap and probably have a strip laying around somewhere I can include if that's okay with you.

I think 47k, 10k, 1k and 470 should be plenty, as well as 100pf and 270pf Silver mica. Please send some snubber caps if you can.

Awesome!!

Thanks,

Pete

[luvdunhill]

a few things. First, the 35mm diameter caps are too big to allow proper airflow around the R2,R3 resistors that will be dissipating some heat. I'm going to have to change to 30mm caps for those with the upgraded kit and I'll keep the 35mm 22,000uF cap for the off board smoothing cap.

Also, Digikey is out of 2 important parts, namely C12 and C13 for the RIAA circuit. Part numbers are P3864-ND and P3884-ND (Panasonic 1% polypro caps). I'm not sure where else you can even order these parts, but I'd like to keep the 1% tolerance if at all possible. I have everything added to a cart so we need to decide what to do about these important, missing parts.

Looks like they are expecting them to be in stock around 08/28/2008...

[DigiPete]

"Looks like they are expecting them to be in stock around 08/28/2008..."

Maybe order from Mouser?

[Pars]

How about 2%? Digikey has the BC 416 series (Morsel likes these alot)

BC2068-ND for the 0.047uf

[luvdunhill]

Pars:

Thanks for the recommendation!

All:

So, I ordered the parts tonite. Total order was around $800.

I had to add heat pads for the TO-220 devices to our order and I'll throw in the nuts, bolts, isolation shoulder washers and lock washers...

I also decided to use something else for C4 and C6. Since some people are using larger capacitors, it would be nice to scale up the bypasses. Also, the speced capacitors don't fit very well, so I decided to use BC1626-ND for C4 and BC1631-ND for C6. I think MKT will be fine here. If anyone objects, I have some of the Panasonic P capacitors in various sizes and can put something together for you.

After talking with customer service, they are going to hold the order until I tell them to release it. They say that P3884-ND should be in stock "any day". This is the only back order item. I also got the remaining 5 or so P3864-ND (1%) and added enough P3473-ND to match the remaining value for this spot in the RIAA circuit.

Time to sit back and wait for PCx to announce their specials and wait for the parts to arrive at Digikey.

[DigiPete]

Awesome!!

Thanks for all the great work you are doing.

Much appreciated:prettyprincess:

[luvdunhill]

I think 47k, 10k, 1k and 470 should be plenty, as well as 100pf and 270pf Silver mica. Please send some snubber caps if you can.

Awesome!!

Thanks,

Pete

So, 47k will just be no loading resistor. I still recommend including a 100 ohm option.

I'd recommend a quick read of this for everyone:

Hagerman Technology LLC: Cartridge Loading

Also, I forgot to include the RIAA resistors in the above BOM for PCx and it seems that PRP doesn't carry some of these values. Some are available in Holco though. Another option would be some Roederstein Resista from Percy, or perhaps he has the required values. I'm still investigating this. Main issue seems to be the 500R R19 value.

[luvdunhill]

a quick update. The toroids have arrived. The cases are in powder coating right now, and they expect to ship the middle of this week. I've contacted Digikey a few times and they are in the process of expediting the order from Panasonic for the P3884-ND parts. They will contact me today or tomorrow with a new ETA. I also sent everyone information for the remaining order at PartsConnexion, but they have not announced any discounts yet. Perhaps they will after their holiday (today).

Thanks!

-Marc

[luvdunhill]

Also, I'm very much leaning towards using the Toshiba parts. I have plenty on hand and it would allow this group buy to get finished up sooner, as there won't be a dependency on the other group buy.

I'd like to charge $20 for the 12 2sk170BL and they will be grouped into 2 quads and 2 tightly matched pairs.

[DigiPete]

Also, I'm very much leaning towards using the Toshiba parts. I have plenty on hand and it would allow this group buy to get finished up sooner, as there won't be a dependency on the other group buy.

I'd like to charge $20 for the 12 2sk170BL and they will be grouped into 2 quads and 2 tightly matched pairs.

Marc,

Sounds reasonable to me.

Pete

[luvdunhill]

PartsConnexion order shipped today. Since it was a large order in $ terms, it was upgraded to UPS. I'll have it soon. Now to annoy DigiKey some more...

[luvdunhill]

Last night I got all the resistors and such sorted into kits. I also received the Russian teflon bypasses and had a chance to try them out on some other projects and I am very impressed. I don't think they will disappoint. No updates from Digikey, they're still trying to get a ship date from Panasonic. I have a bit of soldering to do for a couple people, and then I'll start in on the JFET matching this weekend. Once I get the JFETs matched and the cases arrive, I'll probably just break down and go with the lower tolerance part from Digikey so we can get the parts shipped and the show on the road.

[swt61]

[luvdunhill]

I also got the cases today.

Did I say it was going to be a tight fit?

Basically, I think there is only a single good config. The toroid mounted against the front plate, and the 2 caps and bridges mounted to the bottom panel, right up against the front plate. Thus the PCBs will be moved to the back corner, away from the IEC inlet. It will be close, but it should fit. Remember that diodes emit RF and should be placed away from any input / output lines, and of course the same applies for AC lines.

I really like these cases for the money. They look kinda crappy, until you get them assembled... then they are nice and sturdy. With a nice front panel made from wood, I think they'll be very nice. Also, it's about a small as you can get this project, in terms of case volume... trust me