I think I ought to be building this preamp, looks like it sounds great.
I can't find answers to a couple of questions... does the SMD V4 mean there are SMD components ? Looking at the board, I can't see any and the essentials kit is all through hole ... but the abbreviation might mean something else in this case ? The 2sk370s I've seen are through hole, maybe they're now SMD ?
Is there a BOM ?
Thanks
I can't find answers to a couple of questions... does the SMD V4 mean there are SMD components ? Looking at the board, I can't see any and the essentials kit is all through hole ... but the abbreviation might mean something else in this case ? The 2sk370s I've seen are through hole, maybe they're now SMD ?
Is there a BOM ?
Thanks
I'm exceptionally biased... but I kinda like it.
As ZM noted... they're there, but they're wee tiny. Placement is indicated below (one example). The kits come with those components pre-soldered and tested.
Everything you need should be in post #1 (and links from post #1). If not, just shout.
I have had both versions of this preamp before and after SMD. I think that I am using the before SMD version now. Anyway, in my experience I found them to be identical. So that really means these both are some of the better sounding equipment that I have ever owned. I think that this due mainly to the transformers used in the build as well as a solid design behind them. For me, the sound is a bit forward and that is exactly what I want in my system because some of the other components don't bring themselves out to that degree. As always, this is a system sound for me and not just the preamp all by itself.
Said it before, sayin it again: Iron Pre with the M2X is amazing in my system.
If only I were capable of stopping at that....
🙃
If only I were capable of stopping at that....
🙃
Congrats and enjoy. I concur.
Pearl 3—>Iron Pre—>M2X (Ishikawa 1st; 8 boards left to try) sounds awfully good out of LX-Mini or Zu DW speakers. Unfortunately, or is that fortunately, i can’t stop either. Looking at building speakers and open to suggestions….
Pearl 3—>Iron Pre—>M2X (Ishikawa 1st; 8 boards left to try) sounds awfully good out of LX-Mini or Zu DW speakers. Unfortunately, or is that fortunately, i can’t stop either. Looking at building speakers and open to suggestions….
Many thanks, have found BOM and have Iron Pre SMD balanced essentials and a M2X in basket... plus speaker protection, soft start, transistor mounting pads and some jfets. Already have plans..... could built an integrated amp.
signal iron in IPre doesn't like vicinity of big mains donuts
go figure
build it as other Boyz, in dedicated case
more fun possible, you'll not stop building amps
preamps too
go figure
build it as other Boyz, in dedicated case
more fun possible, you'll not stop building amps
preamps too
Hi all,
I finally got round to make the V4 SE iron pre kit and unfortunately got some magic smoke.
Using 18v parallel PS, measuring 18.5v both sides when powered.
Using a new solder, Stannol Kristall 511, that im not too good at using yet (have always used Cardas previously which was much easier to work with)
Attempt 1:
All seemed good, powered up, no smoke, proceeded with setting voltage.
Left channel measuring 0.67V, trimmer not affecting it.
Right channel measuring 19.3V, trimmer no affecting it.
Decided to reflow all joints before xformers.
Attempt 2 (magic smoke):
After a reflow I noticed I had missed J1 so used a piece of wire to bridge it.
Power up - then a small noise and some magic smoke near the relays.
Then Q2 appeared to be smoking too.
After lifting the board there was a resistor leg hiding under the board near the relays which could possibly have shorted something (I know massive d'oh!).
Any suggestions on how to move forward would be hugely appreciated?
Silly boy Jules
I finally got round to make the V4 SE iron pre kit and unfortunately got some magic smoke.
Using 18v parallel PS, measuring 18.5v both sides when powered.
Using a new solder, Stannol Kristall 511, that im not too good at using yet (have always used Cardas previously which was much easier to work with)
Attempt 1:
All seemed good, powered up, no smoke, proceeded with setting voltage.
Left channel measuring 0.67V, trimmer not affecting it.
Right channel measuring 19.3V, trimmer no affecting it.
Decided to reflow all joints before xformers.
Attempt 2 (magic smoke):
After a reflow I noticed I had missed J1 so used a piece of wire to bridge it.
Power up - then a small noise and some magic smoke near the relays.
Then Q2 appeared to be smoking too.
After lifting the board there was a resistor leg hiding under the board near the relays which could possibly have shorted something (I know massive d'oh!).
Any suggestions on how to move forward would be hugely appreciated?
Silly boy Jules
In modushop the zen mod panel shows what looks like four stamped cut-outs for two pairs of XLR output but it's too blurry to read the label, PCB only shows one output. Is this correct as the 6L6 build only shows one output ?
Thanks, that's what I was going to try, but given the work and effort that's gone into the design, I thought it was a bit simplistic.
if you had smoke around Q2 ....... there is a drill
all Q2 surrounding components - check for shorts, replace what's Dodo; if in doubt for any part - pull it, measure, replace if needed
or
without actual checking - replace:
D3, D4, R1, R5, R6, Q1, Q2
now, for future, when writing - always measure, write down and report:
positive rail value, negative rail value , buffer Iq , buffer DC Offset
all Q2 surrounding components - check for shorts, replace what's Dodo; if in doubt for any part - pull it, measure, replace if needed
or
without actual checking - replace:
D3, D4, R1, R5, R6, Q1, Q2
now, for future, when writing - always measure, write down and report:
positive rail value, negative rail value , buffer Iq , buffer DC Offset