Hi zenmod! Looks great. And those $200 AVC's look interesting too!
With regards to the diamond buffer, what is the benefit of the current mirror over a CCS of some kind? And how did you tune it to a similar distortion structure as the jfet complementary buffer?
if you look again at buffer schematics , BD transistors are doing all work , while small JFet (MMBF5486) is working as 5mA CCS , which is , again , biasing current mirrors up and down on rails
so , there it is , you have CCS
THD spectra is result of currents and voltages involved
besides - that Diamond buffer is hardly anything new under the sun
I did write that ..... AVCs are on Hitachi Metglas cores , my own custom ones
winder is not exactly Beautiful nor Virgin ....... but he is a friend
maybe I'll open Trade thread later tonight , but all technical info is ( I think) already there
regarding Cinemags and Jensens ........ we can mention them only in context of Iron Pre , which is pretty similar but certainly enough different beast - distinctions already written about more than once
Jensens deliberately chosen for Iron Pre pcbs , by 6L6 ..... I'm not doubting his choice and reasons
I believe you will get them and JFets , as part of Store package
winder is not exactly Beautiful nor Virgin ....... but he is a friend
maybe I'll open Trade thread later tonight , but all technical info is ( I think) already there
regarding Cinemags and Jensens ........ we can mention them only in context of Iron Pre , which is pretty similar but certainly enough different beast - distinctions already written about more than once
Jensens deliberately chosen for Iron Pre pcbs , by 6L6 ..... I'm not doubting his choice and reasons
I believe you will get them and JFets , as part of Store package
yup
there are wirepads on board for regular pot (right after selector) ; cut trace between pads, include pot ;
wire any other autoformer instead of AVC
that speaking of Iron Pumpkin
speaking of Iron Pre - 6L6 is having first pcbs ; I can always edit gerbers to accommodate pinout for other autoformer
there are wirepads on board for regular pot (right after selector) ; cut trace between pads, include pot ;
wire any other autoformer instead of AVC
that speaking of Iron Pumpkin
speaking of Iron Pre - 6L6 is having first pcbs ; I can always edit gerbers to accommodate pinout for other autoformer
Last edited:
You're bloody beautiful
I know
Attachments
Hi Zen-Mod,
Impressive work. No wonder it took a while.
I'm thinking about the Iron Turtle SE AVCs and whether they can be used for multi-channel preamp applications. In particular, for my case, for digital crossovers.
I don't need the capability now, but if investing in the Iron Turtle AVCs, it would be nice if they would work in that application in the future.
So can the SE AVCs be ganged via the flat cable or is that capability just used on the balanced AVCS?
Or could there be a special rotary switch with multiple flat cable outputs?
The Iron Turtle ability to tweak output gain per channel would be another plus for multi-channel applications.
Impressive work. No wonder it took a while.
I'm thinking about the Iron Turtle SE AVCs and whether they can be used for multi-channel preamp applications. In particular, for my case, for digital crossovers.
I don't need the capability now, but if investing in the Iron Turtle AVCs, it would be nice if they would work in that application in the future.
So can the SE AVCs be ganged via the flat cable or is that capability just used on the balanced AVCS?
Or could there be a special rotary switch with multiple flat cable outputs?
The Iron Turtle ability to tweak output gain per channel would be another plus for multi-channel applications.
yup
you can daisy chain control of Iron Turtle ......... at least 20 of Turtles controlled with one rotary switch
edit - that's why I put place for two 50pin pcb connectors on Turtle pcb
so , besides having flat cable going through connector to second (etc.) connector (sorta as IDE cable having Master and Slave connectors) , there is also possibility of second cable
so , dress/organize them as most convenient
you can daisy chain control of Iron Turtle ......... at least 20 of Turtles controlled with one rotary switch
edit - that's why I put place for two 50pin pcb connectors on Turtle pcb
so , besides having flat cable going through connector to second (etc.) connector (sorta as IDE cable having Master and Slave connectors) , there is also possibility of second cable
so , dress/organize them as most convenient
Last edited:
Zen Bro, Regarding your statement:
"Disclaimer – as for difference to almost all AVCs on market , these aren't intended to be Swiss Knife universal jobbies , they are constructed to be driven with buffer or , at least , pretty potent signal source apparatus."
How potent? (thinking of output impedance of DACs and also tube buffers)
"Disclaimer – as for difference to almost all AVCs on market , these aren't intended to be Swiss Knife universal jobbies , they are constructed to be driven with buffer or , at least , pretty potent signal source apparatus."
How potent? (thinking of output impedance of DACs and also tube buffers)
say that anything above 50R of Rout is anyway wimpy , at least by my standards
I did wrote in Iron Pre thread , speaking about Iron Pumpkin development , that Iron Turtle is easily driven with Toshiba JFet complementary buffer
that's it ......
regarding tube buffers - I like tubes , and exactly because of that ,I know that there are no many tube buffers around , being both capable ( cojones) and linear ( not compressing one side of signal ......
for small signal , you can hardly beat Toshiba JFet buffer
I did wrote in Iron Pre thread , speaking about Iron Pumpkin development , that Iron Turtle is easily driven with Toshiba JFet complementary buffer
that's it ......
regarding tube buffers - I like tubes , and exactly because of that ,I know that there are no many tube buffers around , being both capable ( cojones) and linear ( not compressing one side of signal ......
for small signal , you can hardly beat Toshiba JFet buffer
- Home
- Amplifiers
- Pass Labs
- Iron Pumpkin(s) and other smaller vegetable animals