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

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hello!
this is a new gyrators equalizer, it has been designed by PPA(Pierpaolo) for500rack
He has sent me 4 prototype pcb 's and  I have assembled them with his schematic.

It uses old and modern inedit discrete  topology using doa's
the gyrators use germanium transistor
it sound great! i like it so much.

This eq has a vintage sound -mids, basses are very good but high are fantastic
it has the particularity to not change the features of the sound at max boost/cut as an eq should do.
Moreover, with max gain you don 't keep noise or garbage,very quiet gear

I don't know if Pier Paolo has intention to put it inthe diy market, you shoud ask him!! ;)
dingo.







here with his big brother..




 
looks stunning.    Pier is such an amazing designer the world should know about him.....
 
Can the LED meter be used with the MA1 preamp? I noticed there are connections for it on the board. I also  noticed that there are several taps for potential add ons to the preamp. Are there any plans to do so?

Thanks!

Paul
 
Potato Cakes said:
Can the LED meter be used with the MA1 preamp? I noticed there are connections for it on the board. I also  noticed that there are several taps for potential add ons to the preamp. Are there any plans to do so?

Thanks!

Paul

Yes, I am developing a meter with 8 LED's for MA1. 
 
Sorry for all the questions, but can you give me the dimensions of the APP992 DIP8 PCB? I am wanting to change out the ICs in some of my existing gear with this, but don't know if it will fit in some of the spaces. Do you also offer this as a dual opamp so I can use them instead of ICs like the NE5532?

Thanks!

Paul
 
Potato Cakes said:
Sorry for all the questions, but can you give me the dimensions of the APP992 DIP8 PCB? I am wanting to change out the ICs in some of my existing gear with this, but don't know if it will fit in some of the spaces. Do you also offer this as a dual opamp so I can use them instead of ICs like the NE5532?

Thanks!

Paul

I am going to send you an email with all dimensions and features

 
A little feedback on app 2050 installed in a classic api 312.
The doa compared to the 2520 have more level of dynamics, more headroom, more bandpass and fastest transient.
Obviously it's a modern doa and it's less "compressed"  then the 2520 but still have the classic "mid forward".
For me it's incredible on acoustic instrument and in 24v "mode"  is quite usable for classic music.
Thanks Pier Paolo
 
Hi Pier, in the last time i've assembled some different DOA's models

But at the end i've choose Your superfast APP992 to implement an analog stage for a custom AD converter ( using PCM4222EVM) that i'm cooking
 

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From the first preliminary test Your DOA 992 seems to catch transients really well

: )
 

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Ops...and i have forgot to thanks You Pier cause i've ended my mic pre too using Your APP1040 pcb.

As You can see i've experiment a bit using a neutrik NTM4 input transformer paired with proper resistor value. The out transfo is a Cinemag ...and the doa is a neumann oa10

...and the results is outstanding ( at least for me)
 

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Pier, is a High integrity kind of guy. I've been happy with the opamps & preamps I've ordered from him
so I'll be checking out the  APP992 fet DOA .........................
 
Hi Pier,

thanks for APP992´s.

Hope, that my solder joints are OK... I'll see (hear) in a few weeks :)

MV
 

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Vac11, if i'm not mistaken, you have mounted the DOA's upside down. They should be mounted atypical of other DOA mountings (i.e. PCB traces facing upward).
 
druu said:
Vac11, if i'm not mistaken, you have mounted the DOA's upside down. They should be mounted atypical of other DOA mountings (i.e. PCB traces facing upward).
You´re right druu,all are upside down ::) 
Look here:


http://groupdiy.com/index.php?topic=49711.msg633968#msg633968


Best,


Udo.


Edit:Link attached
 
Hi All,

the first version APP992 was  upside down, instead the actual version (from a few of years ago) is normal as Vac11 did.


Pier Paolo
 
 

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