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

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I'd like to take 4 of APP2050. I'm in Thailand. Can you ship to my country?
my email is minguta(at)hotmail(dot)com

Cheers.
Minguta.
 
yes, I can ship to Thailand with registered mail service.
kind regards
Pier Paolo
 
hello! Pierpaolo
I'd like to take 2 or 4 of APP2050.
are available? price ?
I am in italy
thank you!
dingo.
 
and the new APP99F with APP2055
 

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Excellent product development work going on at APP studio ing. I hope you don't mind if I re-cap your products briefly. I'm doing this mostly for myself.
APP2050 = standard, Class A DOA.
APP2050E = high Class A DOA.
APP2055 = FET version of APP2050.
APP10 = new low-noise DOA.
APP99F = new FET DOA.

I realize the APP99F is brand new. Could you post some spec's on that module if possible? How does the APP99F differ from the APP2055? How do they compare sonically? I believe I will want at least two of each of these in the near future. I will e-mail you Pier Paolo when I figure out what I need. Thanks, DANA.
 
Tubemooley said:
Excellent product development work going on at APP studio ing. I hope you don't mind if I re-cap your products briefly. I'm doing this mostly for myself.
APP2050 = standard, Class A DOA.
APP2050E = high Class A DOA.
APP2055 = FET version of APP2050.
APP10 = new low-noise DOA.
APP99F = new FET DOA.

I realize the APP99F is brand new. Could you post some spec's on that module if possible? How does the APP99F differ from the APP2055? How do they compare sonically? I believe I will want at least two of each of these in the near future. I will e-mail you Pier Paolo when I figure out what I need. Thanks, DANA.


the APP2055 it's an APP2050 fet version and it's also different from APP99F in circuitry and sound.
APP99F derives from the je-990 using FET in its front-end. Moreover, it's different from 990 also for its frequency compensation circuit. I use a "modern" and inedit frequency compensation circuit inside it, so APP99F has more stability than the original 990, than in the APP99F the RL network is no required in any case.

Regarding sound APP99F it's a bit different from je-990, even if many things are similar between them, because, in an op amp, the front-end is a thing important to give sound character. Currently I use 2sk170 fets (strong mached) in the APP99F. Its sound is much "airy" and a bit warm but very clear, moreover, like the other APP DOA's has very fast transients.

Currently, I'm trying to modify again the 99F from the original je-990 and for that I have not made in the market the 99F yet, even if , I precise, the current APP99F version is very good.  



 

 
 
Beautiful. That is EXACTLY what I wanted to know. As you said, the input transistors have a huge influence on the overall sound of any amplifier. Let me think about this new info here. Thanks Pier Paolo. DANA.
 
Payment sent for PSU kit. Looking forward to get pieces together and start building PPA powered micpres :)
 
Hi Pier I ordered 4 op amps to add to my other 2  and 1 of your new mic preamp psu kit,great intro price and the psu  looks to be high quality too! Thanks again
 
Pier,

How is the development of the APP2050 GERMANIUM progressing? :)

Can you describe the sound of this DOA?

What will be the power supply requirements Voltage and current?

Thanks!
 
I have a prototype of 2050GE and I'm doing tests.

2050GE is a modern circuit opamp that uses old transistors, but the old germanium sound look is inside 2050ge.
It sound very warm with fast transients and high dynamic. There are a lot of harmonics in its sound.
Being a very low distortion opamp has not the distorted sound of old circuits.
The sound is totally different from a silicon bipolar transistors or fets input opamp, it's more similar to tube sound than silicon sound, but it has several different aspects of the tube sound as the type of warm and the very fast transients, the very big and fast basses. 2050ge is ideal for acoustic and electric guitars, the piano is fantastic, the voice is very warm and very real. 2050 ge opamps make very real many instruments, it's incredible.

regarding specifications:

input currents = - 2.2 uA typical
supply voltages = from +/- 12 V to  +/- 16V
max out current = 250 mA
quiescent current = +- 24 mA no load
input offset voltage= 5mV typical



thanks

Pier Paolo
















   












 
>>>
>>>
2050GE is a modern circuit opamp that uses old transistors, but the old germanium sound look is inside 2050ge.
It sound very warm with fast transients and high dynamic. There are a lot of harmonics in its sound.
Being a very low distortion opamp has not the distorted sound of old circuits.
The sound is totally different from a silicon bipolar transistors or fets input opamp, it's more similar to tube sound than silicon sound, but it has several different aspects of the tube sound as the type of warm and the very fast transients, the very big and fast basses. 2050ge is ideal for acoustic and electric guitars, the piano is fantastic, the voice is very warm and very real. 2050 ge opamps make very real many instruments, it's incredible.
>>

I can't wait to try one out!  :D

Do you have an estimation of when you will begin selling the 2050GE?

Thanks!
 
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