JRC4557

[Davefx]

Does anyone know where to get one of these chips, or is it even worth it? Mainly because I wanna build the Quazar (RC version) and it is said that that is the chip.... Sorry if this is a redundant request.

Dave

[jkokura]

I've not heard of it. What has your searching turned up? The best thing to do would be to find a datasheet and then see if you can either find a substitute if you can't find one, or perhaps you're out of luck.

Jacob

[Haberdasher]

I've never heard of that one.  I would probably just use TL072 or JRC4558.

If you're shopping at mouser don't search for JRC, they list them under the company's newer name NJM- for example NJM4558.

[jkokura]

Oh wait. I think I know what the problem is.

The Gliterati project mentions a 'jrc4557'. I think that's a typo man. The 4558 or 4559 is probably what was meant there. Madbean might confirm that, but if you google the JRC4557, there's no such thing.

Jacob

[JakeFuzz]

This was supposedly the actual chip in the RC a booster. I did some research a while ago when a friend of mine wanted one of these and it is an actual chip. They are super rare, there is one company out of the UK that sells them but I don't have the link. Honestly I wouldn't spend that much effort on a chip. I would just get a Burr Brown chip for that circuit. Goes along with the high fidelity and transparent theme i think.

[Davefx]

Thanks!  Right, I'm not going to bother.  BUT what are these Burr Brown chips that everyone talks about?

[JakeFuzz]

Thanks!  Right, I'm not going to bother.  BUT what are these Burr Brown chips that everyone talks about?

Burr Brown is a brand under Texas Instruments. They make all sorts of stuff but a part of their line is high speed opamp's. They have a really high slew rate and bandwidth. Most of the BB chips I have used are really clear sounding, good for things like transparent boosts and other low distortion applications. Most people would like to use them for everything but they are pricey at usually around 4 bucks for an average BB chip. I think it is a perfect chip type for the RC booster because the RC is low drive and typically used as a transparent booster with a powerful active EQ. Your next best bet is probably an NE5532 or a TLE2072. Try a few out and see what you think, you can pick up most from Tayda for a few cents. 

[Davefx]

Thank you kindly!  BB sounds like a plan to me.  Yeah right, screw tryin to find the 4557.  Clear transparency is what we want, and I have a few 5532s' so I'll start there. Thanks again everyone!

Dave

[Davefx]

Talk about ADHD!! I blindly looked over the link to that British supplier for the chip!!  Sorry guys,  .

[JakeFuzz]

Oh you found it! Yeah I found that site almost a year ago trying to build an exact RC. Can you repost the link so people have it? Thanks.

IIRC shipping was what killed it for me. I just put an NE5532 in there. If you do get one let us know how it sounds compared to other dual opamp's if you have any on hand. I would be very interested to see if Xotic used these for any specific reason. 

[Davefx]

Well it's in the "Projects" in the quasar project.
http://www.dalbani.co.uk/catalogue/product_details.php?id=27344

I've decided to just experiment with some Burr-Browns and the 5532.  I'd imagine the 5532 would be a great choice to start as well as it was a standard chip in a lot of quality mix boards in the past.

Dave

[JakeFuzz]

Ahh right, thats where that UK link came from. NVM thanks for posting it anyways.

Yeah I love the NE5532, its inexpensive and it sounds very clear. I had one in my timmy for a while, sounded really good.