you have nothing to worry about. the LM317/337 are floating regulators and have npo ground pin, as long as you do not short them to ground, they have no idea what voltage they are being fed, all that matters to them is the input/output voltage differential; which is WELL within spec. you could feed them 600v as long as you wanted 560v or more output
Normaly Caddock has not the 390R value.
See here the Datasheet:
http://www.caddock.com/Online_catalog/Mrktg_Lit/MP9000_Series.pdf
I hope you get really the right resistors.
390R is ok. You get 2,6% less audio output level.
I would say, the non-inductive-design is important for the circuit performance.
then you can take a low or non inductive Ohmite, Caddock or Bournes.
I also think the quality of the C28, C29, C51, C52 is very important.
The best capacitor is no capacitor. I would take a good capacitor and bridge them with a little silver mica (Glimmer).
regards
Horst
there is indeed 390R caddocks, yes, by geeves you may be onto something, the output caps are important??... hehe just joking, but yeah they are indeed. I eventually will be using some jantzen superior bypassed with VCAP CuTF (already have 2 spare, need to pick up another pair) first up i'll just use some cheaper AVX polypropelenes I have on hand. all of this until I get around to playing with a JFET servo. owen any ideas on a servo? did you consider it for this build and if so what turned you off, lack of simplicity?
no problems guys. will let you guys know when they arrive. they wont be here straight away because they have to take a detour through floccini's place due to them not shipping direct to OZ. also queried mouser about the ohmite thin films and was quoted 18 weeks and 500 piece minimum order 
so the search continues. i'm also going to check out the price on the TZ220 Zfoil power resistor for the 400R, but know they wont be cheap. theres only a couple of places to bling this build up, and I figure this is one of them.
opc, have I got the right email for you mate? sent you another email last night to let you know a couple of things and clarify my bill.
so the search continues. i'm also going to check out the price on the TZ220 Zfoil power resistor for the 400R, but know they wont be cheap. theres only a couple of places to bling this build up, and I figure this is one of them. opc, have I got the right email for you mate? sent you another email last night to let you know a couple of things and clarify my bill.
Hi Guys,
Congrats on organizing the FET group buy. There seems to be quite a few people who were having trouble sourcing the fets, so it's good to see that there's a resource if need be.
I'm getting very close to having my board up and running, so I'll let you all know as soon as I do. I'll toss in a few pictures when I'm done. I was up way too late working on it last night...
For those who haven't built up a mixed board like this before, make sure you solder the every SMD part before you do anything else. It's tempting to solder on all the big parts first, but it will make the SMD parts impossible to do.
qusp:
Sorry for the delay in getting back to you... I was up quite late soldering boards and didn't put any time into this yesterday. I'll get you the circuit I used for matching my fets, and tell you exactly how I did it. You'll need a heatsink for the fet, a few voltmeters (you can me due with one, but it's more difficult) and an adjustable supply. Otherwise, the test circuit looks a lot like one branch the actual circuit, which is a good thing.
NicMac:
As qusp mentioned, absolutely every SMD part that is on the board in included in the SMD kit. I did it this way to minimize shipping size and keep my costs down.
richluvsound:
I'm going to guess that there will be at least one or two more people dropping out, so you can probably still get a board. There are a few people on the list who put their names in early, and I haven't heard from them since. I'll give it a few more days, then I'll send out emails to those who haven't paid.
You're second on the wait list, and I'll let you know soon if you've got a board or not.
Felipe:
Thanks for catching that omission on the list... I know you had asked, but it slipped my mind. Just to be clear, you want both your board cut right?
I'll update the list accordingly.
Regards,
Owen
Congrats on organizing the FET group buy. There seems to be quite a few people who were having trouble sourcing the fets, so it's good to see that there's a resource if need be.
I'm getting very close to having my board up and running, so I'll let you all know as soon as I do. I'll toss in a few pictures when I'm done. I was up way too late working on it last night...
For those who haven't built up a mixed board like this before, make sure you solder the every SMD part before you do anything else. It's tempting to solder on all the big parts first, but it will make the SMD parts impossible to do.
qusp:
Sorry for the delay in getting back to you... I was up quite late soldering boards and didn't put any time into this yesterday. I'll get you the circuit I used for matching my fets, and tell you exactly how I did it. You'll need a heatsink for the fet, a few voltmeters (you can me due with one, but it's more difficult) and an adjustable supply. Otherwise, the test circuit looks a lot like one branch the actual circuit, which is a good thing.
NicMac:
As qusp mentioned, absolutely every SMD part that is on the board in included in the SMD kit. I did it this way to minimize shipping size and keep my costs down.
richluvsound:
I'm going to guess that there will be at least one or two more people dropping out, so you can probably still get a board. There are a few people on the list who put their names in early, and I haven't heard from them since. I'll give it a few more days, then I'll send out emails to those who haven't paid.
You're second on the wait list, and I'll let you know soon if you've got a board or not.
Felipe:
Thanks for catching that omission on the list... I know you had asked, but it slipped my mind. Just to be clear, you want both your board cut right?
I'll update the list accordingly.
Regards,
Owen
cool, not sure what the spread is on these parts normally, but having already got a few enquiries and wanting to keep a fair chunk of matched devices myself, I may not be able to guarantee many more matched sets, especially lots of 8. 100 doesnt go all that far normally.
i'll still have some devices, but at some point will not have the time or the ability to supply matched sets. I did this mainly so myself and flocchini could have some and fill in a gap for you guys too, but have no desire to make a little business out of matching devices, I already have my hands full. as I said in my post on the matter initially, I will do a small number and after that will sell some unmatched until I only have what I want to keep left.
just wanted to make sure I was clear so there are no misunderstandings. it may turn out that the spread is not so wide and is easier, but will only know that when I receive them
excellent mate!! looking forward to the pics
absolutely, the biggest hint there is, start with lowest and work your way up, do that and you'll be fine. oh and flux, make sure you have some good tweezers and some flux
no problem mate, mainly just wanted to make sure I still had the correct address as I had not heard from you and seeing the list fill up with my name still not paid doesnt feel good, even though its all on the level and i'm just waiting for your go ahead. so dont rush on my account mate, just checking.
cool on the test jig, just let me know. I only have one meter that I would use here as my other one is just a trashy one I use to keep a rough eye on the power supply when working on signal or vice versa, but can organize a second; really should be getting myself another one anyway with the F5 coming up. have everything else in spades
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