correct + inside of cap symbol circle
ignore that one outside of circle
pic from post #1, tnx to IAIMH
ignore that one outside of circle
pic from post #1, tnx to IAIMH
ZM is that for SE board only? Or also balanced? I don’t see the same silk as IAIMH screen shot in BAL boards
sorry, I didn't look at pic of your boards
you're good
omission is on SE boards......
as written by IAIMH:
edit: in short, covering all boards:
- if plus marks are same pin orientation in and out of cap symbol circle - obey it
- if plus marks are different pin orientation in vs. out of cap symbol circle, obey inside one, ignore outer one
you're good
omission is on SE boards......
as written by IAIMH:
edit: in short, covering all boards:
- if plus marks are same pin orientation in and out of cap symbol circle - obey it
- if plus marks are different pin orientation in vs. out of cap symbol circle, obey inside one, ignore outer one
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If anyone is building one of these (like me) using the Slagle $300 AVCs, I have four extra pairs of PCBs for mounting the AVC with an Elma 04-1133-20 switch. I've been using these for the past year or so in a passive preamp and they work great.
I'm building a dual passive/active Iron Pre with AVCs, and I dug up these up as it seems they may be of use to people given the popularity of this project.
(H/T to @nautiboy who originally designed this PCB and was kind enough to share the design with me -- more details in this thread https://www.diyaudio.com/community/threads/slagle-intact-autoformer-volume-attenuators.330822/)
Cost will just be actual shipping from the US to wherever you are. Just PM me with your shipping address.
I'm building a dual passive/active Iron Pre with AVCs, and I dug up these up as it seems they may be of use to people given the popularity of this project.
(H/T to @nautiboy who originally designed this PCB and was kind enough to share the design with me -- more details in this thread https://www.diyaudio.com/community/threads/slagle-intact-autoformer-volume-attenuators.330822/)
Cost will just be actual shipping from the US to wherever you are. Just PM me with your shipping address.
Thanks for the interest -- all four sets are now spoken for!
Where can I find a pair of switches? elma switch 04-1133-20
The only place that has them online is in Germany, I don't know if they'll ship to the USA.
Banzai Music
The only place that has them online is in Germany, I don't know if they'll ship to the USA.
Banzai Music
The 04-1133-20 switches are available from both Don Audio and HiFi Collective -- I can confirm both ship to the US!
Don't forget stop screws to stop the switch from turning past the max volume on the AVC: https://www.don-audio.com/Elma-Type-04-A4-A47-Switch-Stop-Pin-Screw -- not critical to proper functioning, but nice to have (and these screws are not something you can just pick up at Home Depot)
Don't forget stop screws to stop the switch from turning past the max volume on the AVC: https://www.don-audio.com/Elma-Type-04-A4-A47-Switch-Stop-Pin-Screw -- not critical to proper functioning, but nice to have (and these screws are not something you can just pick up at Home Depot)
Has anybody tried 0dB of voltage gain on their Iron Pre? Wondering what it might sound like as a buffer.
some posts back, I posted graphical how to
saving precioussssss iron for something else, if you don't need gain
how is it going to sound - as good buffer, how else?
saving precioussssss iron for something else, if you don't need gain
how is it going to sound - as good buffer, how else?
I haven’t tried it on the Iron Pre, my boards aren’t mounted yet. I do have a protoboard version of the B1R2 with a shitty PSU, But doubled up high IDSS JFETs for more current and xcon, and lower Zout (12,5 ohms) and - like the IP - no series output resistors. Sounds extremely natural and punchy, and with enough gain. Now, that transferred to the IP with it’s superb PSU etc, would definately be worth trying if one does not need more gain.
That said, I perhaps think that the lowest gain setting with a Cinemag had a tiny bit more drive than without. Then again, that may have been just the added gain and my ownn biases providing that drive
I don't believe putting signal through a 1:1 transformer is going to the same as taking the output off the buffer. If someone has tried it, great, it saves me the experiment. One could even generate balanced output that way, using the center tap.
