SOAP MKIII (Simple OpAmp Pre) With onboard PSU

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Z

zei

Member
Joined 2005
I,m not shure what (if any) benefits there would be running an OpAmp at lower voltage (Within the recommended range of course)

Most of the times all this info is in the datascheet but i think that the only reason that they can take a range of different voltages is that it increases the numbers of applications they can be used in.

If i remember correctly the E5532 max voltage is +-22V
Opa2134 has a max V of -+18V


lets hope someone else has something more intteresting to say about this :)

I say +- 15V because it is a number :) No other reason ;)

/JZ
 
P

Puffin

Member
Joined 2006
I had assumed that the caps at C15 - C18 might have been to provide DC blocking. I assume I am wrong. If I add caps on the output, what values do you suggest.

Trippy. For safety purposes I wear thick gardening gloves and use just spent matches to solder with as my mum told me not to play with hot things as I might hurt myself. My PCB's look like burnt pizza.
 
Tripmaster

Tripmaster

Member
Joined 2008
Puffin, I have a PCB just like yours but with a slightly different topping, if you know what I mean?

They say you cant educate pork! ;)

Anyway...where are all the other builders posts, its been three weeks since I built mine, I'm sure Zei will be keen to know how you are all getting on :)

Richard
 
Tripmaster

Tripmaster

Member
Joined 2008
Puffin said:
How do you find yours after 3 weeks, any significant burn-in differences?
Click to expand...



Puff meister

During the first week I used 2.2uf Vishay capacitors at positions C15 and C16 and a pair Icel MWR 4.7uf caps at C17 and C18 (as pictured in a previous post), The sound was OK but I felt the bass sounded a bit flabby.

The following weekend I purchased some rather nice AMPOHM 3.3uf polyprops at an Audio Jumble near Leatherhead. That evening I decided to de-soldered the old capacitors and replaced them with the AMPOHMS...What a difference! the bass became tight and deep, there appeared to be a higher level of detail I had not previously experienced. I then swapped the OPA2132PA for the LM4562...yet again a noticeable improvement.

I auditioned several opamps, the OPA2132PA (FET), OPA2134, AD826ANZ and LM4562.

I didn't like the AD826, the OPA213PA sounded nice and the OPA2132PA had a warm signature but lacking the crisp sparkle of the LM4562.

I am currently making some aluminium cases to house my Chipamp and SOAP-Pre, I will post a couple of pictures when completed.


Richard
 
Mush

Mush

Member
Joined 2005
Alternative to Black Gate N/NX for SOAP

Hi Everyone,
I am having trouble finding 4.7uf N/NX Black Gates for coupling. The AMPOHM 3.3uf sounds great but I'm in the US. Does anyone know a source for the Black Gates or AMPOHM in the States or a good alternative cap for the SOAP mkIII that's availabe here?
Thanks for all of your posts. It's been very educational.
Ciao -- M
 
G

gabanyayaya

Member
Joined 2008
zei said:
I,m not shure what (if any) benefits there would be running an OpAmp at lower voltage (Within the recommended range of course)

Most of the times all this info is in the datascheet but i think that the only reason that they can take a range of different voltages is that it increases the numbers of applications they can be used in.

If i remember correctly the E5532 max voltage is +-22V
Opa2134 has a max V of -+18V


lets hope someone else has something more intteresting to say about this :)

I say +- 15V because it is a number :) No other reason ;)

/JZ
Click to expand...

zei,

If I'm using a 15V tranny would it be possible to remove the trimpot????

Do I have to adjust the voltage if decided to keep the pot?
 
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