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

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muffy1975 said:
Yeah the LM317 is hot. :eek:

But i have 24V ;D So that's now very good

The +48v is reading 60V when not beng used, and when being used with a microphone is measuring 48V Is that correct?

Michael

You are using a trasformer for 230V AC input, you are in UK so the AC voltage is 240V , moreover,  probably, this one is more than 240V because in many countries the effective voltage is highter than the nominal.
Moreover, you are using a trasformer with 25V secondaries for 24V DC on PSU's out, and, there are the trasformer's tollerance too, so, at this point, there is an high voltage across the LM317, but it's not a real problem, but an high voltage gives high power to dissipate. I have designed the heatsink for less voltage across the LM317 for a good temperature margin (85°C with 40°C of ambient) becuse the normal conditions are others than yours.
For your PSU currently conditions I've calculated an LM317's internal temperature near to 85°C with 25°C of ambient temperature , but since the PSU will go inside a chassis that will go inside a rack we should consider 35-40°C of ambient temperature instead of 25°C, so the LM317's internal temperature might be near to 100°C in a rack. The LM317 limit temperature is 125°C. At at this point I council a bigger heatsink than those is now mounted.


Rearding the phantom power the mic never sees 60V but only +48V , but to avoid to have 60V on this out you can solder a resistor of 15K 1/2W between GND and the phantom out.

Pier Paolo

 

 
naths101 said:
ppa said:
naths101 said:
Interested in the APP2050 germanium, do you have an ETA?
Cheers

Scuse me but what means ETA ?



sorry, 'estimated time of arrival'... that is when will they be available?
thanks

the lead time is around a week.
the shipping time for Australia is around often one week or two max.

Pier Paolo
 
Ok,

please don't be angry with me.....but my volt meter is/was  wrong. I Checked the mains voltage and it said 250V....???? So my meter needed a new battery. Now the mains reads 240V

I have reset everything, put the pSU back as was before...I believe R3 was 5.6K right?

YOUR PSU RULES AND IS NICE AND CLEAN and the Voltages are spot on. The heatsink is not too hot.

Thankyou so much for your product

Michael

and sorry for running up a whole page of your thread with my dodgy volt meter ;)
 
thanks for the compliments,

yes the original R3 resistor is 5.6k

don't worry for the time, it's important that the PSU was modified to run for neve preamps.

Pier Paolo
 
hello!! Pierpaolo!!
just finisched my 312 pre with your  2050 and 2050e
tested in studio session on drum,guitars and bass ....SOUNDS FANTASTIC!!!!
wery clean ,super fast  transient on snare  and kick ,huge on guitars !!
working with 18 V  will try 24v
much better comparated to my api512c!!!!
will try on passive eq like pultec.... and passive summing buss
good job!!! :) :)
thank you!!
dingo.
 
bplastic77 said:
Hey Pier Paolo,
I would like to order 2 APP99F's
thanks
Brian :)
Hi Brian,
2X APP99F are 2X26 Euros = 52 euros = 70.3 US $ ,  S&H and paypal fees are included in the price.
It's possible paying in US $. The paypal payment for no european customer is to [email protected], for european customer is [email protected] (It's for the strange italian fiscal laws) 
k regards
Pier Paolo
 
a power amp that I'm developing
 

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the prototype amp under testing , it's a 250W/4 ohm amp.
 

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pre mic with new topology (not 312) , it's a prototype so the silkscreen it's absent.
 

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Govinda Doyle said:
When will the germainium op amps be ready?
what voltage do they run?
And what is the sound like compared to your other op amps?
Cheers
Govinda
thanks for the interest,
I've sold on pre-selling several germanium opamp to my old customers on these days.
It's ready.
APP2050Ge runs with supply voltages in range +/-12V to +/-16V.
It's hard to describe the germanium sound, but I can write that it has the typical color of the old germanium gears but with high dynamic and the modern sensation of low distortion (infact it has low distortion). It has a very warm sound with high definition.

My others opamps sound different between them.

kind regards
Pier Paolo



 
ppa said:
Govinda Doyle said:
When will the germainium op amps be ready?
what voltage do they run?
And what is the sound like compared to your other op amps?
Cheers
Govinda
thanks for the interest,
I've sold on pre-selling several germanium opamp to my old customers on these days.
It's ready.
APP2050Ge runs with supply voltages in range +/-12V to +/-16V.
It's hard to describe the germanium sound, but I can write that it has the typical color of the old germanium gears but with high dynamic and the modern sensation of low distortion (infact it has low distortion). It has a very warm sound with high definition.

My others opamps sound different between them.

kind regards
Pier Paolo

dang! I was hoping to use the germanium with a +- 24volt rail, i want an op amp that has the smoothest high mids clear but warm what would you recommend? once i find one i like i will be ordering about 32 or 64!
Thanks so much for the speedy reply!
Govinda
 
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