Sorry Tom, I've just go through e-mails, and I see that I did sent you all necessary info and I was sort of waiting for you to decide are you going for one or two stereo sets
Anyhow, will reply pronto with another e-mail
as written in my sig here - If I didn't reply on PM or e-mail, just repeat, and don't be mad
Anyhow, will reply pronto with another e-mail
as written in my sig here - If I didn't reply on PM or e-mail, just repeat, and don't be mad
Working on it
though, xperience with various generations of SissySIT, sound difference is not big at all
only if you compare two gens directly, but even then difference between Silmic in signal path vs. DC all the way is smaller than possible difference in crucial OS parts ...... SIT in case of SissySIT, LU in case of LuDEF
though, xperience with various generations of SissySIT, sound difference is not big at all
only if you compare two gens directly, but even then difference between Silmic in signal path vs. DC all the way is smaller than possible difference in crucial OS parts ...... SIT in case of SissySIT, LU in case of LuDEF
I'm wondering if the LuDEF would be happy driving a pair of 16 ohm speakers? ..Anyone have experience of this? I'm thinking of trying mine on some vintage Goodmans drivers.
Hey! Why would we ever avoid the most amazing speaker cables the world has ever known?avoid high capacitance speaker cables


For those without context... I LOVE the LuDEF. I had a big scare though. It performed flawlessly on the bench and with test speakers. When I put it into my main system, I heard the most awful distortion. I thought I'd fried something in my speakers. After a day of panic / gnashing of teeth and (of course) guidance from ZM... I swapped out my 30+ y/o audiophool speaker cables for something a bit more pragmatic; et voila... no more crazy distortion; just beautiful music.
As a side note - those cables would find a new owner, but I can't stomach the thought of someone paying more for them than the copper value.
YMMV.
Can I drive the OS with Iron SE ? or other your amp ?LuDEF is happy driving anything, and the other way around
exception being, as is for all amps I made having Square Law OS and no feedback - avoid high capacitance speaker cables
they're drek, anyways
You can direct drive the VAS transformer with an AmpCamp plus pre, also the Salas DC coupled one.. It was @tombo56 who covered this before..
https://www.diyaudio.com/community/threads/ludef.369990/page-35#post-6845895
Interested to learn if a Pumpkin/ Iron pre can replace the VAS transformer and input buffer
https://www.diyaudio.com/community/threads/ludef.369990/page-35#post-6845895
Interested to learn if a Pumpkin/ Iron pre can replace the VAS transformer and input buffer
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calculus is simple
SQ OS, as in LuDEF is having zilch voltage gain
Iron Pre SE is having either 6 or 12db, so 2V/V or 4V/V
consider regular 2Vrms from source, that's 8Vrms max, which is (P=Urms^2/Rload) 8W@8R
see Booh and Pooh for more inspiration
https://www.diyaudio.com/community/threads/the-marriage.390965/#post-7140686
SQ OS, as in LuDEF is having zilch voltage gain
Iron Pre SE is having either 6 or 12db, so 2V/V or 4V/V
consider regular 2Vrms from source, that's 8Vrms max, which is (P=Urms^2/Rload) 8W@8R
see Booh and Pooh for more inspiration
https://www.diyaudio.com/community/threads/the-marriage.390965/#post-7140686
Amazing amp 😎😛
Spending a few hours on sacrificial speakers before going into the main system
Spending a few hours on sacrificial speakers before going into the main system
Thanks 😊Congrats, which PSU did you go for Brian?
I rebuilt an F6, that was built with the DIYA stores, universal PSU board and 88000 uF per rail, fed by a Toroidy audio grade 400 VA 18+18 VAC. It sounds amazing!
I think i will try and upgrade it with active rectifier and Tombo56 regulator addons for CRC - at some point 😎
PM me if you want a pair of active rectifiers, I've an advert somewhere.
Still sounding spooky 😎 graduated to main system.
More porn - thermal images are taken at RT 24 degC.
More porn - thermal images are taken at RT 24 degC.
What Lu bias have you gone for?
The ZM prescribed 2.4 V, i might play with other voltages later 😋
Bias is 1.5 A, in a 4U400 chassis.
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What pre are you using with it?Still sounding spooky 😎 graduated to main system.
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