Hi Guys,
Sorry for the slow down on this project... I'm at the rather painful prototyping/measurement stage which is very time consuming. I'll post some early measurements when I get them done.
I was thinking I would just fire off the boards untested, but going to three layers really increases the cost, and I don't want to end up with 50 useless boards because I didn't take the time to build and test each circuit. Even thought they're essentially the same as "The Wire" it's better safe than sorry.
All three versions and the PSU are finished in terms of layout, so it shouldn't be long now.
If there is anyone interested in these boards or kits, feel free to post up your requested quantities as nothing has been ordered yet, so the list is still open. I'll update the list later on today since I haven't done that in a while.
Thanks again to everyone for bearing with me... these things always take longer than expected to complete.
On a fun side note, I had about 2 square inches of board space left over, and I have a really kick-*** phono preamp that just might fit there. It's also in prototype stages, but I might be offering it up here if it works out as well as I think it will. It's all jfet, fully differential, two stages with low impedance RIAA, only three components in the signal path (including the jfets) and it only needs a single +40V supply. If you're into vinyl, I think you're going to like it! I'll be feeding the output directly into the new BAL-BAL headphone amp for a fully differential system from the pins on my DL-103, to the transducer terminals of my AH-D2000 headphones. If anyone has any questions, send me a PM to prevent this thread from going too far off topic. I'll open a new thread when I've got more details.
Cheers,
Owen
Sorry for the slow down on this project... I'm at the rather painful prototyping/measurement stage which is very time consuming. I'll post some early measurements when I get them done.
I was thinking I would just fire off the boards untested, but going to three layers really increases the cost, and I don't want to end up with 50 useless boards because I didn't take the time to build and test each circuit. Even thought they're essentially the same as "The Wire" it's better safe than sorry.
All three versions and the PSU are finished in terms of layout, so it shouldn't be long now.
If there is anyone interested in these boards or kits, feel free to post up your requested quantities as nothing has been ordered yet, so the list is still open. I'll update the list later on today since I haven't done that in a while.
Thanks again to everyone for bearing with me... these things always take longer than expected to complete.
On a fun side note, I had about 2 square inches of board space left over, and I have a really kick-*** phono preamp that just might fit there. It's also in prototype stages, but I might be offering it up here if it works out as well as I think it will. It's all jfet, fully differential, two stages with low impedance RIAA, only three components in the signal path (including the jfets) and it only needs a single +40V supply. If you're into vinyl, I think you're going to like it! I'll be feeding the output directly into the new BAL-BAL headphone amp for a fully differential system from the pins on my DL-103, to the transducer terminals of my AH-D2000 headphones. If anyone has any questions, send me a PM to prevent this thread from going too far off topic. I'll open a new thread when I've got more details.
Cheers,
Owen
What are the dimensions of the new PSU board? Any chance you could post an image of the layout? I'm doing a bit of planning for the my next case.
Also, when do you estimate the kits will ship? I'm moving across the country in late August (off to college) and I don't yet know what my new address will be.
Keep up the good work
Thanks,
Nelson
Until OPC do the hard job we can discuss about parts.
As for part recommendation what do You think about using tantalum resistors? It is said they sound similar to the Vishay bulk metal ones. Not many high quality SMT resistors are available but I saw this IRC (mfg.) PFC series SMT resistors looking good. As always it is not easy to find a dealer in EU, but at Farnell they cost about 1-2$ each which is below my (upper) price margin. Anyone heard them?
The datasheet is here:
http://www.irctt.com/file.aspx?product_id=161&file_type=datasheet
Oh, and they have 0.1% tolerance.
As for part recommendation what do You think about using tantalum resistors? It is said they sound similar to the Vishay bulk metal ones. Not many high quality SMT resistors are available but I saw this IRC (mfg.) PFC series SMT resistors looking good. As always it is not easy to find a dealer in EU, but at Farnell they cost about 1-2$ each which is below my (upper) price margin. Anyone heard them?
The datasheet is here:
http://www.irctt.com/file.aspx?product_id=161&file_type=datasheet
Oh, and they have 0.1% tolerance.
I might try out the phono, which jfets? 40v seems a bit high for the usual suspects.
yeah i've used the IRC resistors, pretty decent, i usually stick with high grade susumi, vishay PAT or pnm series and of course for highest grade signal path the zfoil smd at about 7-8 dollars each. in general i dont like tant resistors, i dont believe they are similar to foil at all.
hey we have our own forum in the main section now!! well done mods
yeah i've used the IRC resistors, pretty decent, i usually stick with high grade susumi, vishay PAT or pnm series and of course for highest grade signal path the zfoil smd at about 7-8 dollars each. in general i dont like tant resistors, i dont believe they are similar to foil at all.
hey we have our own forum in the main section now!! well done mods
1. Do you prefer a board only, or a full kit? Board only.
2. Would you rather have a PSU included or not? PSU board incluaded.
3. Would you be interested in a fully balanced version (bridged output with two LME49990) or the existing version? Existing version (BAL - SE)
4. How many units are you interested in? 1
2. Would you rather have a PSU included or not? PSU board incluaded.
3. Would you be interested in a fully balanced version (bridged output with two LME49990) or the existing version? Existing version (BAL - SE)
4. How many units are you interested in? 1
I've found something else I'm going to use, sorry. Please remove me.
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Owen, whats up mate?, i think you are losing everyone to the O2. imo your amp is the better of the 2 (and the O2 doesnt offer balanced in or out, which is imperative to me) speaking just of amp circuits (the O2 has a pretty interesting psu), obviously the O2 is the more complete portable package and does seem to be a good design, me, i prefer to use higher performance parts and without caps in the signal path, regardless of whether i can hear the difference, it makes me feel better
without contact or movement here they will continue to depart and tbh mate i cant say i blame them. we know you are busy and i totally understand that, you gotta pay the bills, but probably best to not take on these projects if you cant find the time to complete them.
without contact or movement here they will continue to depart and tbh mate i cant say i blame them. we know you are busy and i totally understand that, you gotta pay the bills, but probably best to not take on these projects if you cant find the time to complete them.
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