Lm4702

[metal]

Metal, don't be childish. I know my limits, I had no clue about this chip until I talked to those who do know. I was just trying to pass on information.

I was throughing an advice here, and it was serious !!

Don't be so sensitive, and understand things the way you like

 

[Russ White]

That's peanuts for my pre.
I just thought it would be better to advice not to use a volume pot directly on this circuit.
You never know what people can do.

Right its peanuts for a lot of pres. And you point was well taken.

 

[demogorgon]

I am especially excited about using some other output devices.

me too.
never really saw the need for darlingtons.

 

[Russ White]

I was throughing an advice here, and it was serious !!

Don't be so sensitive, and understand things the way you like

I am sorry, I thought you were being a smart @ss, I truly apologize if you were not. Instead I guess I should thank you.

 

[metal]

I am sorry, I thought you were being a smart @ss, I truly apologize if you were not. Instead I guess I should thank you.

I am a smart @ss now, thanks russ, but, shame on you calling me that way in deed.

 

[carlosfm]

Right its peanuts for a lot of pres.

Not a lot of pres, really.
But for a current-feedback video op-amp that is made to drive 50 ohm loads and has 500ma output current into a 10 ohm load, it's a piece of cake.

 

[Russ White]

I am a smart @ss now, thanks russ, but, shame on you calling me that way in deed.

Ok well if thats the case then there is no shame, just pointing out the obvious.

 

[Russ White]

Not a lot of pres, really.
But for a current-feedback video op-amp that is made to drive 50 ohm loads and has 500ma output current into a 10 ohm load, it's a piece of cake.

Sure, even for a single pair of OPA627 this 680R would be a simple load.

 

[metal]

Ok well if thats the case then there is no shame, just pointing out the obvious.

Then you are blind, and pointing in the wrong direction

 

[Russ White]

I am interested to see how the amp sounds both with the 33uf Nichicon ES alone as Ci/Cin and byapssed with the 1uf film cap. But if past experience is any guide it will sound better bypassed. I have actually never used an input cap that big.

 

[carlosfm]

Sure, even for a single pair of OPA627 this 680R would be a simple load.

But with more distortion.

 

[Russ White]

Wow! You must get some pretty low distortion with that then carlos. Because the distortion of the OPA627 even at 680R is very low ideed.

I know the AD8620 has even better distortion with low Z loads then the opa627.

I may try that pre of yours! Actually I have always meant to.

Cheers!
Russ

 

[Russ White]

Just so you all know, Metal and I simply had a failure to communicate which can happen quite easily to anyone. We have undertood eachother now, and we are quite excited to keep working on this project. So please ignore the noise above. It was an honest mistake, and a case of an itchy trigger finger on my part.

My appologies to the group.

Cheers!
Russ

 

[metal]

Just so you all know, Metal and I simply had a failure to communicate which can happen quite easily to anyone. We have undertood eachother now, and we are quite excited to keep working on this project. So please ignore the noise above. It was an honest mistake, and a case of an itchy trigger finger on my part.

My appologies to the group.

Cheers!
Russ

Ok Russ,

Its all over, new white page, new life, I think that cisco router was translating our words in the wrong way, and we fixed that now

My apaologies to all members here, including russ, the group, and...I don't know to whome else

 

[chipco3434]

Group hug!

Hug it out!

Ya!

 

[Gcollier]

Is Carlos using an AD8620 or and AD815 in his pre. I have been working on a design for an AD815 pre...might be a nice combination with this amp.

Russ I'm looking forward to seeing your boards when they are done, still using the good old toner transfer method? Anybody given any thoughts on powering this thing? I doubt we'll be seeing any regulators at these voltage levels How much capacitance are we going to need for this beast?

 

[Russ White]

Hi G,

I was not trying to imply Carlos was using AD8620, I was simply throwing that opamp out in comparison to the OPA627. I think he was talking about the 815 as you suggested.

Well I botched my first PCB, and I am going to make another tonight or tomorrow. I will post PICs soon.

My first PS will likely Be pretty simple 10,000 uf x 2 per rail unregulated and I am shooting for 50V rails. I may get more fancy later. I just want to get the thing running first.

Cheers!
Russ

 

[motherone]

Its all over, new white page, new life, I think that cisco router was translating our words in the wrong way, and we fixed that now

Damn those cisco routers! If it were Junipers, it would've worked properly the first time!

 

[metal]

Damn those cisco routers! If it were Junipers, it would've worked properly the first time!

I think cisco router is working now

 

[carlosfm]

Is Carlos using an AD8620 or and AD815 in his pre. I have been working on a design for an AD815 pre...might be a nice combination with this amp.

I was talking about the AD815, alone.
That's what I use.
Here's a quite acurate description of how it sounds, from a member that built it exactly following my schematic:

http://www.diyaudio.com/forums/showthread.php?postid=758916#post758916