APP Studio Ing's products - APP992 - APP14GE Germanium DOA and other kits

Hi Pier, I'm definitely in for 4 of these.
Cheers.
Alberto

I would like to close the group buy at 50 pcs or after 10 days.

since these boards need to be powered I offer at only 5 euros one PSU2 board for each two IO pulteq boards bought, this is special price I do to the diy prodigy members.

Pier Paolo

Hi Pier,

I'll take a pair of the Pultec boards, and a PSU board (or kit if there's one available).

Thank you,
Ruairi

I'll take 2 pultec boards and 1 PSU board too Pier.
cheers
Chris

I'l have 2 psu boards with my existing order of 4 pultec boards...

hi pier

im interested in the Ge DOA's, do u still have any stock?

would these be a straight swap on a 312 circuit and would they be ok on +/-18V??

cheers
mick

Hi Pier, Does your pultec board do one or two channels ?

Thanks man!
-jonathan

0dbfs said:

Hi Pier, Does your pultec board do one or two channels ?

Thanks man!
-jonathan

Click to expand...

one channel only

thanks
kind regards
Pier Paolo

Thanks Pier, I'll go with six channels worth of pultec I/O boards and three PSU's please.

Much appreciated !

Best,
jb

leadbreath said:

hi pier

im interested in the Ge DOA's, do u still have any stock?

would these be a straight swap on a 312 circuit and would they be ok on +/-18V??

cheers
mick

Click to expand...

no, because in these days I have had several orders for this one,
however I am going to start the SMD version (except for the germanium transistors that are PH) so I will have a big stock of them (we speak of working 20 days of time lead). The SMD version is upgraded so it is better sounding.
The SMD resistors in the signal path are panasonic metal film type (top level and expensive).    

the 2050 germanium version is rated for +-16V of power supply

kind regards
Pier Paolo



   

I'd like 1 PSU board to go with my 2x IO board order.

the 2050 germanium version is rated for +-16V of power supply

Click to expand...

ok understood, thanks pier

and the mill max pins are compatible on the 312 pcb?? (for polarity)

leadbreath said:

the 2050 germanium version is rated for +-16V of power supply

Click to expand...

ok understood, thanks pier

and the mill max pins are compatible on the 312 pcb?? (for polarity)

Click to expand...

yes, they are

I have not had the time to follow this too closely...do we need these to compliment ruffrecords pcbs?

It would be really nice to get some more info on these IO boards.
Here, http://www.groupdiy.com/index.php?topic=43859.120
I can see the board, but its hard to find out how it works and which connections are needed.
If you cant put up a schematic, how is about a block diagram?
Where is the board manufactured? China or Italy?
Estimated delivery date would also be helpful...
Thanks for your effort in making these board

Ptownkid said:

I have not had the time to follow this too closely...do we need these to compliment ruffrecords pcbs?

Click to expand...

Ruffrecords has designed the passive eq net, this net needs an input and an output stage to compliment ruffrecords pcbs.

Moreover, Ruffrecords has designed a tube out stage for his passive eq net too.
Using this tube stage and a line trasformer as input stage it is possible to have a complete inductorless pulteq eq1a

But the Ruffrecords' out stage is based on tubes, who wants a solid state input and out stage to compliment ruffrecords pcbs
can be use this my IO board, if he want.  

I would like 2 I/O boards and 1 PSU please.



Thanks Pier!

Andreas Pfeiffer said:

It would be really nice to get some more info on these IO boards.
Here, http://www.groupdiy.com/index.php?topic=43859.120
I can see the board, but its hard to find out how it works and which connections are needed.
If you cant put up a schematic, how is about a block diagram?
Where is the board manufactured? China or Italy?
Estimated delivery date would also be helpful...
Thanks for your effort in making these board

Click to expand...

yes , I am going to put up the shematic tomorrow.

the connections are:

input stage (gain= 0.5 or 1 , 24 dbu)
- balanced line input with 20K of input impedance, that 's the line input of the gear.
- sbalanced out to connect to the passive eq net's input (ruffrecords' eq boards)

fet buffer stage (gain = 1,  12 dbu, note that the passive eq stage attenuates a lot the signal)
- sbalanced 2.2M input from out of ruffrecords eq boards
- sbalanced out

makeup gain stage and out stage (20-36 db of gain max, 24dbu - 32 dbu out,  depending by configuration used)
- sbalanced input 47k of impedance, the signal cames from buffer stage out
- balanced trasformerless out 
- balanced out with trasformer (several trasformers can be used in)
- connector for potentiometer for make up (25k rev log or 10k rev log)

connector for power supply , dual voltage

tomorrrow other infos, now I am going to bed

this is the schematic, soon the other docs

this is the image