Iron Pre Essentials Kits For The DIYA Store - Register Your Interest

[Zen Mod]

May I lower R3/4 combo to approx 3ohm for additional CCS to power NP 6-24 crossover from the pos rail.? It requires 120mA and if I keep spare CCS to the 80mA I create no more heat in M1. Is the rest of the circuit happy with that?!

you may, allowing proper heatsinking of BD and IRF devices of Good Gemini (code name for shunt reg of Iron Pre), and appropriate size of xformer; for approx 220mA of programmed current, steady juice (for just one secondary/rail) is 0A22*18V=3.96W

for that, no less than 30VA Donut

but, fact is that seating both Iron Pre pcb(s) and Papa's Xover in one enclosure isn't so easy and both of them are really deserving own separate case for best wiring arrangement, you're in situation of needing long wires from shunt regs to Xover pcbs, pretty much no-no in my book, negating benefits you have of (any) regulated supply

also, no small Donut is happy with unequal loading of secondaries; you can do that with xformers dedicated to auxiliary circuits, but not advisable for xformers where center tap is used as direct connected audio GND

in short - I wouldn't do that

 

[jimk04]

That's a good answer thanks . I appreciate the explanations.

 

[Gianluca]

Just a quick heads up for those who have ordered the Iron Pre chassis in the last days: all orders have been shipped and by the end of next week you should all receive your cases. Happy building!

 

[jimk04]

Would love one of the official chassis...! One day maybe. !

 

[tamra]

Hi Zen Mod,
What I asked about transformer was Auto-transformer. So I am planning to build one.
There is metglas core and finemet core version.
Do you find different sound quality?

 

[Zen Mod]

Finemet is giving even more low level information, through entire spectrum

Very!! far from Metglas being bad, but Finemet is better

Not much, but it's in our nature to always shoot for overkill

anyhow, when you have completed AVC with switching, connection is as per sketch in post #2113

 

[tamra]

Thank you so much.
Price is not that big difference so I don't want to regret later.

 

[Zen Mod]

if wiring is clear, good

if not, just buzz here when you get them, preferably with some data(sheet)

 

[MEPER]

If I have free choice of BC546/556 A,B,C types. Which type is preferred? A?

 

[Zen Mod]

that's "just" beta subdivision

in practice, any will work good enough

 

[MEPER]

Ok, but if you use BC546A then you will also use BC556A .....so be able to sleep well (symmetri)?

 

[Zen Mod]

naah

just chill

some drek really doesn't need matching or even too much thinking

 

[MEPER]

OK!

One more thing:

I have some AWG30 wire wrap cable on the way for the input wiring (silvered ).
I was thinking about the technical reason for using very thin wires for input.

Is it primarily to have theoretical same impedans for all frequencies (e.g. 20 - 100 Khz):
https://www.powerstream.com/Wire_Size.htm

I was also thinking about when those thin wires are twisted then the coupling is very close and then maybe less chance for e.g. magnetic noise to couple to the "cable"?

 

[Zen Mod]

there are many technical explanations why thin conductor should/is sounding better for small signal

though, you can hear/read them all, then you're in same situation as plain Believer - if you need to ask, then certainly you don't have knowledge and/or necessary apparatus to actually test and confirm/deny said claims

so, I'm stuck on tasting and not testing - thin signal wires are best to my ears, in my system setup logic

and I believe that Buddha is everywhere

 

[MEPER]

Ok,
I have an unfinished experiment using twisted PTFE silvered wire cables as RCA cable. I never got them terminated.
It was to make a very cheap DIY RCA cable that has low capacitance and immune to magnetic fields. For RCA I would connect black and blue to Gnd and red to hot (could be used for XLR also I assume).

Now with AWG30 I could try the same and it should work very well? ......better then XXX $ cables?
Apart from a maybe little problem with physical strength.......it could be fun to try.

Maybe a little bit off topic......but as you can see.......IP-schematic is included.......

 

[richmain]

I am having trouble finding a transformer in the UK any suggestions.

 

[Neat Ripple]

Toroidy deliver to the UK.
Or Bonsai has spoken highly of Tiger Toroids:
https://www.diyaudio.com/community/...igher-canterbury-windings.392366/post-7410486

 

[twocents]

Or try RS Components UK
RS stock no.: 752-9306

 

[MEPER]

If power transformer try Toroidy (Poland):
https://sklep.toroidy.pl/en_US/c/Toroidal-transformers-SUPREME-AUDIO-GRADE-V2/99
Very silent. I used it for IP-SE and will used the same for IP-BAL.

 

[davidjt]

Or maybe: https://airlinktransformers.com/category/chassis-mounting-toroidal-transformers