A New Take on the Classic Pass Labs D1 with an ESS Dac

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opc

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Hi Guys,

Schematic is finalized, and the BOM is finished as well. You can find them both attached below. I've put the parts in as what I would select if I were building this as a "Sensible Audiophile".

The most expensive parts are the polypropylene film output coupling caps at $10 each, followed by the Caddock resistors at $3.50 each. I would imagine many will want to use their own coupling caps, but these fit nicely, and they're what I'll be using.

I'm having trouble sourcing the 400 ohm Caddock MP930 1%, and the DK number on the BOM for that part is made up. 400R is listed on the datasheet as a standard value, so if anyone knows where to get it, let me know. Maybe with a GB we can get all the Caddock parts at once and save a little cash.

Otherwise, all the parts are listed with DK numbers, so feel free to look things up and make comments or suggestions for anything you feel could be improved. $52 resistors are not going on my short list, however.

I took a look at the Linear LT317/337, and they look like they'll drop right in for anyone who would like to spend a little more on regs.

One final issue I'm having is finding any 0.200" pitch inline board to board connectors. I've looked all over Digikey, and I can't find anything. I needs connectors to go between the bottom of the Buffalo II (spacing fixed at 0.200") and the top of my board (also space at 0.200" to match the Buffalo). I don't really want locking ones since it's completely unnecessary for this application. I basically want your standard 0.1" header/socket but with 0.2" spacing. If anyone knows where to get these I would appreciate it! I need a 2 pin, 3pin and 5pin version, although the 5 pin could be replaced with a 2 pin if needed.

Cheers,
Owen
 

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they arent 52 anywhere sensible. they are 14 singly normally and thats ridiculous, I did a full double take when I saw that insane price at mouser

the LT1083/LT1033 should drop right in as well and these are much better

0.2" board connectors aree rare as hens teeth, just use the 0.1 and remove every second pin. i'll find the stacking headers, but I dont know that DK has them, both ELFA and mouser have them though, perhaps a GB because they are a bit unreasonable
 
Last edited:
Member
Joined 2009
Paid Member
Hi Guys,

Schematic is finalized, and the BOM is finished as well. You can find them both attached below. I've put the parts in as what I would select if I were building this as a "Sensible Audiophile".

The most expensive parts are the polypropylene film output coupling caps at $10 each, followed by the Caddock resistors at $3.50 each. I would imagine many will want to use their own coupling caps, but these fit nicely, and they're what I'll be using.

I'm having trouble sourcing the 400 ohm Caddock MP930 1%, and the DK number on the BOM for that part is made up. 400R is listed on the datasheet as a standard value, so if anyone knows where to get it, let me know. Maybe with a GB we can get all the Caddock parts at once and save a little cash.

Otherwise, all the parts are listed with DK numbers, so feel free to look things up and make comments or suggestions for anything you feel could be improved. $52 resistors are not going on my short list, however.

I took a look at the Linear LT317/337, and they look like they'll drop right in for anyone who would like to spend a little more on regs.

One final issue I'm having is finding any 0.200" pitch inline board to board connectors. I've looked all over Digikey, and I can't find anything. I needs connectors to go between the bottom of the Buffalo II (spacing fixed at 0.200") and the top of my board (also space at 0.200" to match the Buffalo). I don't really want locking ones since it's completely unnecessary for this application. I basically want your standard 0.1" header/socket but with 0.2" spacing. If anyone knows where to get these I would appreciate it! I need a 2 pin, 3pin and 5pin version, although the 5 pin could be replaced with a 2 pin if needed.

Cheers,
Owen

The MKP can be purchased at Parts Connexion: Axon MKP 22uF 250V (D: 28.5mm x L: 43mm) at 4$64 each instead the Epcos a 10$60 each

AXON True Cap Metallized Polypropylene Capacitors

Q1-4 at Mouser 1€21 = 1$66 instead 1$94 at DK
 
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they arent 52 anywhere sensible. they are 14 singly normally and thats ridiculous, I did a full double take when I saw that insane price at mouser

the LT1083/LT1033 should drop right in as well and these are much better

0.2" board connectors aree rare as hens teeth, just use the 0.1 and remove every second pin. i'll find the stacking headers, but I dont know that DK has them, both ELFA and mouser have them though, perhaps a GB because they are a bit unreasonable

Hi

The LT1033 is now obsolete unfortunately. LT recommend LT1185 as a replacement, which is crazy as it's a 5 pin reg!!

LT337 should be good enough for the negative reg do you think? And LT1086 is the positive 1.5A version and is cheaper than LT1085. Very very good regulators.

It may worth getting them direct from LT.

http://www.linear.com/pc/productDetail.jsp?navId=H0,C1,C1003,C1040,C1019,P2050

http://www.linear.com/pc/productDetail.jsp?navId=H0,C1,C1003,C1040,C1055,P1358
 
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forget farnell and RS, both are ripoff!! sumumu are def my favorite thin film and mouser has a good range of them in stock. I prefer mouser mainly because of the free international fedex 2 day shipping after 200 dollar order ;). of course there is the SMD zfoil range, but they are like 14 dollars a pop, though I still may choose 1 or 2 positions worthy of them ;) just because. of course I just made a 400 dollar order with mouser yesterday, but I usually make a regular order every 2 weeks; hows that BOM going Owen?

qusp:
Can you share what you consider the worthy positions?
Any further thoughts on how to use with Acko's board?
Nice suggestion on the headers ;)
Best
Bob
 
Hi

The LT1033 is now obsolete unfortunately. LT recommend LT1185 as a replacement, which is crazy as it's a 5 pin reg!!

LT337 should be good enough for the negative reg do you think? And LT1086 is the positive 1.5A version and is cheaper than LT1085. Very very good regulators.

It may worth getting them direct from LT.

Linear Technology - LT337A - Negative Adjustable Regulator

Linear Technology - LT1086 - 1.5A Low Dropout Positive Regulators Adjustable and Fixed 2.85V, 3.3V, 3.6V, 5V, 12V

I have 1085/1033 here; I think you'll find that PCX has the both 1085/1033 still. this is an annoying thing about linear, that they will often have what are suposed to be complimentary devices in utterly different packages.

just woke up, will have a look in a couple hours, flocchini. we have an open house in 45 mins :(
 
indeed they do, bit pricey there though. I already have all the power R's and even film caps that I can reuse, but I would really like to do without them, so am looking for simple effective servo circuits. if the DC offset is constant then it should be easy enough to just feed the output to LPF (to separate signal from DC)->inverting input of opamp or other IC->output to remove it. this is one position where really an opamp is the best part for the job and its not in the signal path really.
 
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Joined 2004
Paid Member
Adding a board for me. Owen - thanks for all the good work.

habsrock93 1
compressit 1
CeeVee 2
flocchini 1
RichLund 1
Nikola Krivorov 1
Greg Stewart 2
qusp 2
frozen wing 1
neb001 2
merlin el mago 2
lauret 2
igwt 2
pidesd 2
ichiban 1
DaveM 1
fitzfish 2
Yunick 1
DiyFan 1
Jacques Merde 2
stephen1212 2
dggs 1
NicMac 1
pierrequiroule 1

Total 35 boards
 
Member
Joined 2009
Paid Member
Hi Guys,

Just a quick note to mention that I'm out of town for the weekend, so I'll be reading but probably not responding until Sunday or Monday.

Cheers,
Owen

Nice wek-end Owen,

Are you sure the heatsinks can be enough to 250mA, I tell that because I'm using the same voltage in my Salas Low Voltage Shunt Regulator +45Vout 500mA to feed my Simplistic Salas NJFET RIAA & I'm using a big one 1ºC/W:

ABL HEATSINKS|345AB1000B|HEAT SINK, 1°C/W | Farnell España

14€76 each!!!!
 
totally different requirements for a shunt regulator, I expect also that you need to have a much higher input/output differential which is all burned off as heat in the shunt element. discrete shunt regulators are notoriously inefficient, where I can put out 500ma at nearly 19.7v with 20v input and only PCB copper traces with a linear LT1763 in soic8 package, no heatsink at all. its the input output Dif thats important and the fact its a linear supply not shunt
 
Adding a board for me. Owen - thanks for all the good work.

habsrock93 1
compressit 1
CeeVee 2
flocchini 1
RichLund 1
Nikola Krivorov 1
Greg Stewart 2
qusp 2
frozen wing 1
neb001 2
merlin el mago 2
lauret 2
igwt 2
pidesd 2
ichiban 1
DaveM 1
fitzfish 2
Yunick 1
DiyFan 1
Jacques Merde 2
stephen1212 2
dggs 1
NicMac 1
pierrequiroule 1

Total 35 boards

-1 :(
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.