That's a good question. I have this Iron Pre SE board sitting here, unpopulated. I successfully desoldered the Jenson JT-123's from my F6 last night, so I have iron to use. My goal is to go iteratively – first build the Iron Pre as intended (with Jensen and a regular pot for attenuator), then pull the Jenson and swap in a Slegle (intactaudio) AVC. I'm partly doing it this way because it'll be a bit before I can afford the AVC 
Another scenario – I build the Iron Pre as-is and leave it that way. I have a nice Salas shunt reg and a B1v2 on a breadboard that I may use with the AVC instead. We'll see...
*edit* for the record, this idea came directly from ZM as I corresponded with him via PM. Nothing new or excited coming from me
Another scenario – I build the Iron Pre as-is and leave it that way. I have a nice Salas shunt reg and a B1v2 on a breadboard that I may use with the AVC instead. We'll see...
*edit* for the record, this idea came directly from ZM as I corresponded with him via PM. Nothing new or excited coming from me
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Iron Pre is intended for Store - Greedy Boyz cheap ticket for Iron Blessing
arrangement (signal route) - inputs - selector, regular pot, buffer (with proper shunt regs on board) , autoformer for gain - out
Iron Pumpkin is full blast, Mana from Heaven, Demonstration of Force
arrangement is - inputs - selector, buffer (with proper shunt regs on board), AVC (settable gain) - out
that's why I told you to take 200$ jobbies , each time in fact, when I mentioned them
they're straightforward and you can set desirable gain as you wish, in same manner as I'm doing it with Iron Pumpkin's Turtle module
more expensive ones are having some trickery with switching, so gain play is not so free for final user
they're straightforward and you can set desirable gain as you wish, in same manner as I'm doing it with Iron Pumpkin's Turtle module
more expensive ones are having some trickery with switching, so gain play is not so free for final user
I know I keep saying it but if you can get a IP in your system. With my Tannoys and either of the F3, the Singing Bush or the SissySIT it as ZM says it is full bast - Manna from Heaven - Demonstration of Force and as a fringe benefit a superb headphone amp.
Disclaimer I don't receive a "kick back" each time I praise the IP - I just know it is that good. Inductors are so much better than resistors I don't see anything replacing it.
Disclaimer
I don't receive a "kick back" each time I praise the IP - I just know it is that good. Inductors are so much better than resistors I don't see anything replacing it.
knowing my blahblah nature, you can expect me saying how, even without you asking
when you get them, let me know
just don't be greedy with gain db
Does one have to sacrifice taps/levels of attenuation to get gain? Say something like 3 or 6 db
you'll always having same number of functional steps, equal to number of taps on AVC
gain is just matter of tap which you're feeding AVC with signal
normal feed point is highest tap (lowest being grounded, logically), where max step is equal to 0db of attenuation and same db of gain
if you move feed one tap lower (example - Turtle having each step of 2db), then result is that max step is 2db above feeding signal, so you're getting exactly same amount of db as signal gain (Vout/Vin)
I don't know exactly what's db table of Slagle 200$ jobies, but certainly appropriate to gain few dbs, if you move feeding point tap or two or three - down
handy sketch , post #4, Iron Pumpkin(s) and other smaller vegetable animals
gain is just matter of tap which you're feeding AVC with signal
normal feed point is highest tap (lowest being grounded, logically), where max step is equal to 0db of attenuation and same db of gain
if you move feed one tap lower (example - Turtle having each step of 2db), then result is that max step is 2db above feeding signal, so you're getting exactly same amount of db as signal gain (Vout/Vin)
I don't know exactly what's db table of Slagle 200$ jobies, but certainly appropriate to gain few dbs, if you move feeding point tap or two or three - down
handy sketch , post #4, Iron Pumpkin(s) and other smaller vegetable animals
Most likely ZM's. I am going to build the balanced Pumpkin in the winter. I will most likely get one (or more) additional AVCs (Turtle Modules) for use in other pre-amps.
The Turtle is the AVC module... I think... for the Pumpkin (or other pre-amps). The two (or four) pre-amps that I know within this "family" are:
1. Iron Pre SE
2. Iron Pre Balanced
3. Iron Pumpkin SE
4. Iron Pumpkin Balanced
Iron Pre (I believe in both its forms) will be offered in the store "soon". I believe the Iron Pumpkin will continue to be only a Zen Mod Labs offering. Wild speculation on the latter. Only MZM knows for certain.
you got it right, on all accounts;
though , Iron Turtle (AVC module) is going to stay as part of Iron Pumpkin, no use of trying to put it any other context, when darn thing is made for exact concept - to be driven with buffer
Iron Pre - Store (so having nothing with me, except that I would need to cover any possible questions)
Iron Pumpkin - no other way than exclusive ZML offering - I'm simply not able to make them in any significant numbers and I'm certainly not foolish enough to outsource them ...... or maybe I'm not capable enough
)interesting thing is - I am not aware of any other truly balanced/differential AVC offering on market (all known to me are one separate AVC per phase, while mine is proper one AVC for both phases); doesn't mean that there is none ....... world is big place
Thanks, I have and know Iron Pre, I kept getting confused between Iron Pumpkin references and Iron Turtle references. I think I have it sorted, Iron Turtle just refers to AVC thing, while Iron Pumpkin refers to entire preamp thing, Turtle and all.
Everyone is answering Iron PRE vs Iron Pumpkin...my silly brain confused Iron Pumpkin and Iron Turtle.
Russellc
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Board went together nicely. Rock solid voltages and buffer offset. Now it’s time to round up a chassis. Plan to listen to stock Iron Pre for a bit, then phase 2 will be AVCs.
Thanks to ItsAllInMyHead for the board and bullet-proof BOM! Accolades to ZM coming soon
Thanks to ItsAllInMyHead for the board and bullet-proof BOM! Accolades to ZM coming soon
Attachments
......Accolades to ZM coming soon
feel free to start with them anytime, no need to wait
I'm pretty much unable of blushing