Any time. For clarity, you were originally asking whether to fuse both line and neutral. That doesn't mean you can't use a single pole switch at all. I just wanted to be sure we're talking about the same thing. Also, in "Schurter speak" don't confuse fuse holder (part of the PEM "body") with the fuse drawer (the part that holds the fuses and slides out). I've seen that cause people to want to throw things... Also for some models, the drawer is an option / separate purchase. 😉Thanks Patrick. It looks like you could use either a single pole or a double pole switch. In the U.S. double poles are usually used for high voltage devices (240V) as it's a safer way to disconnect from the mains when you bring in two 120V lines to an appliance.
Thanks for all the information.
John
Some Options -
Single pole switch - Single Pole Fuse Holder
Double pole switch - Single Pole Fuse Holder
Double pole switch - Double Pole Fuse Holder - Single Fuse with Optional fuse drawer with neutral bridge
Double pole switch - Double Pole Fuse Holder - Dual Fuses
Cheers,
Patrick
It's been a year since I built my balanced version, and during that time only the single-ended were used. Yesterday I hooked the Iron Pre up to my balanced Mark Levinson and it sounded fantastic, and quiet, even though it was placed literally 4" behind the amp which has two enormous toroid transformers. I could detect no induced hum at all, even when I lifted the Iron Pre directly over the ML.
I built another for a friend last year, and he only wanted the single-ended jacks connected, but I think it's really a handy feature to connect at least one position for balanced use.
I built another for a friend last year, and he only wanted the single-ended jacks connected, but I think it's really a handy feature to connect at least one position for balanced use.
And it's done!
Thanks for all the help and inspiration.
Looking good, what does the knob do on the front panel?
Did you enjoy "releasing" your preamp on us?
I don't need you "us" to be in permanent state of joy

@SkyPirate No issues at all with Frank's MUSES setup on a balanced setup or Academy Audio on a single-ended version. Both are great. I honestly can't remember where I got those knobs.
Have fun!
Have fun!
Hi all - I had to take a break from this project. 1) I screwed up the twister board and boneheadedly got the leds backwards. I think the selector actually works but resistor and leds are kaput. Can another be procured? 2) Board measured beautifully and jumper headers finally installed but 3) when twister moved to input 1 (only one I’ve tested) preamp plays full volume on left channel when volume pot full CCW then full volume right when full CW then both channels full volume when 12 o’clock. I know I have red heat shrink on the left cable, bad form. I’ve been reading the threads but cannot find the other instances of this happening. Any help appreciated.
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Can you just cut off the backwards LEDs, desolder the leads, and put in new LEDs the correct way? LEDs are cheap. This is what I used and they worked great with the Modushop chassis.1) I screwed up the twister board and boneheadedly got the leds backwards.
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