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

[Tweekhead]

Pier,

I received the 2 germanium DOAs today and plugged one in for a quick test. It sounds fantastic! I can't wait to try it out on electric guitars. Thanks for the great product, and I apologize for the drama, but seeing as we are unfamiliar with each other, and I only had 45 days for recourse from Paypal I had no other choice.

Thanks again,

Arthur

 

[ppa]

thank you to having bought from me and for comments.
Pier Paolo

 

[ppa]

This is the APP1040 module.
APP1040 pre has a new topology to avoid electrolityc caps in the amplification stage.
It has the DOA's positive input pin directly connected to the DI, as is in the API3124 to do an example.
It is designed for APP DOA's , 2520 , 990, Forsell DOA's and MM99 and others.

I have posted the prototype pics here http://www.groupdiy.com/index.php?topic=33576.240

APP1040 is not a 312 but a new project to be clear, who knows my opamps can have an idea of its performance.
APP1040 can use several trasformers from: Lundhal, OEP, ED trasformers, Altran, jensen , cinemag, JLM, Sowter.

 

 

[creal]

Hello Pier Paolo,

Pm'ed you
I'd like 4 APP2050 for the make up gain in my solid state pultec.

Creal

 

[deuc224]

It has 32 DB of gain?

 

[ppa]

no, it isn't. Its gain depends by trasformers' ratios, the resistors used in the NFB net and the DOA used.
However with an APP2050, the Classicapi input an output trasformers the standard setting gives 64 dB of gain.

 

[creal]

Hello Pier Paolo,
Paypal'ed for the  DOA APP2050 this morning

Creal

 

[ppa]

Hello Pier Paolo,
Paypal'ed for the  DOA APP2050 this morning

Creal

thanks
Pier Paolo

 

[delphi]

I am building 12 of Mitsos 312/990 preamps. I have used JLM DOA's for 4 of them and want use your DOAs for 4 more "2050" types and 4 for a 990 type.

Which of your DOA's do you recommend for the Mitsos design.If all of your 2050 types are OK for this design (I dont want to use servos) - then I would appreciate a comment on the subjective "sound" of each of your DOA's so I can "mix and match.  The 990 versions will all be using 1:2 ratio input transformers, whilst the rest are using 1:5 or 1:6. What would the FB resistor value need to be with a gain pot of 10K? _ I seek a total gain of 60db or better

 

[ppa]

I am building 12 of Mitsos 312/990 preamps. I have used JLM DOA's for 4 of them and want use your DOAs for 4 more "2050" types and 4 for a 990 type.

Which of your DOA's do you recommend for the Mitsos design.If all of your 2050 types are OK for this design (I dont want to use servos) - then I would appreciate a comment on the subjective "sound" of each of your DOA's so I can "mix and match.  The 990 versions will all be using 1:2 ratio input transformers, whilst the rest are using 1:5 or 1:6. What would the FB resistor value need to be with a gain pot of 10K? _ I seek a total gain of 60db or better

I make a version of JE990 I called APP99. This one is similar to JE990, there're differences in the frequency compensation circuit.
My 99 has a new circuit that does not use any inductance (used inside 990 in the 1st stage) and also gives great stability, this new circuit is the same used in the APP2050. The other difference is in its front-end that uses two discrete ultra low noise mached transistors insted the LM394. Moreover, the transistors inside are different types. This APP99 can be used with 1:2 input trasformers.
APP99 run in the mitsos preamp with servo or with out cap.
regarding the pot I am seeing for it.


APP2050 runs in the mitsos preamp set in 312 mode without servo, can be used input trasformers with ratio from 1:5 to 1:10 , I council the 1:7 classicapi in trasformer.

I will you all indications to set the mitsos preamp with APP99 and APP2050 opamps.

 

[JBVries]

Got my 6 PSU boards and I gotta say the quality of these things are absolute tops. Thanks for the great power solution!

 

[ppa]

this is the APP1040's PCB

 

[ppa]

and this is the APP meter2 , this meter is usable with the APP1040 board and with other pres.
Meter2 is based on the LM3915 by National and drives 10 leds, but who want can use less leds.
This board has power supply voltages   in range +- 16V to +-24V.
With the multiturns trimmer can be set fine the 0 dbu led.

 

 

[ppa]

and this is the meter2's pcb

 

[dalmaproductions]

Hi Paolo,
I've tried to contact you via email, and via PM with no success. My email gets: "Delivery to the following recipient failed permanently..".

Is there an email address I can contact you at? Send it via PM please.

Miguel

 

[ppa]

you may contact me to  AMSMicro  [at]  katamail  [dot]  com    , thank you

 

[kepeb]

hey
like the look of your new vu.
do you have a BOM?

 

[ppa]

the meter2's schematic

 

[creal]

Hello Pier Paolo,
Paypal'ed for the  DOA APP2050 this morning
Creal

Hello Paolo,

Any news about the 4 DOA?
I still waiting 2 of them for finish my EQs.
I have a question, do you think, it's a good way to make a 325 API clone as Makeup gain amp for the meq5?
I need 16db gain.

Thx
Cyril 

 

[ppa]

Scuse me for the time, but I am yet waiting the epoxy resin to pot your opamp and other 40.

however these 4 are new SMD version using panasonic metal film resistors in the signal path (very very good resistors), and this nwe version sound much better than the previus. It has a very realistic guitar, for example, with realistic ultra fast transients. Sorry, they need another week to send them.

For Makeup gain you could use a 325 api clone or, if you want, an APP1040 board without input trasformer using its DI input.