AudioRoundTable.com: Silicon Valley » Group Build National Semiconductor amp

Home » Audio » Silicon Valley » Group Build National Semiconductor amp

Show: Today's Messages :: Navigator :: Polls
E-mail to friend

Re: Group Build National Semiconductor amp [message #59301 is a reply to message #10378]

Mon, 25 May 2009 01:02

DanTheMan
Messages: 84
Registered: May 2009

Viscount

Hello, new to the thread. I was just wondering if this was still a possibility or if it is dead in it's tracks.

Report message to a moderator

Re: Group Build National Semiconductor amp [message #59304 is a reply to message #59301]

Mon, 25 May 2009 22:48

Wayne Parham
Messages: 18793
Registered: January 2001

Illuminati (33rd Degree)

I'm still game. We never really did anything with this last time, but I'd definitely still be interested. We could probably buy from Digikey, just pool together to make one order. I'd buy several all by myself. Do you think we should make a post on the Group Build forum and see how many hits we get?

Another one I'd like to do a group buy on is Burr Brown opamps. I need OPA 627 and OPA 404 chips. (See "Active Sub Crossover" thread.) I'll buy dozens of them and that alone should allow a quantity discount. So I probably should make a post in the Group Build forum for that too. We all can take advantage of the quantity to get a price break.

Report message to a moderator

Re: Group Build National Semiconductor amp [message #59397 is a reply to message #59304]

Wed, 17 June 2009 17:10

DanTheMan
Messages: 84
Registered: May 2009

Viscount

seems there is not much interest here Wayne. I'll check over in the group buy. It's possible that everyone is just saving for their next 7 pi build.

Report message to a moderator

Re: Group Build National Semiconductor amp [message #59398 is a reply to message #59397]

Wed, 17 June 2009 20:23

Wayne Parham
Messages: 18793
Registered: January 2001

Illuminati (33rd Degree)

We may be able to take advantage of pooling our purchase, even if there's not many others interested (even if only we two). I am interested in the OPA404, OPA627 and the LM3875 and/or LM3886 chips. I am going to buy at least a dozen of each of the Burr Brown op-amps, so you you want some of those, you can get a quantity discount no matter what. On the others - the LM3875 and 3886 - if we each bought 13, we would qualify for a price break. If others decided to join in before we actually place the order, maybe we could get an even better price. Here are the quantity price break points for those four parts at Digi-Key:

Part           qty          unit cost
=====================================
OPA404KP-ND      1           12.58
                25           11.3252
               100           10.0415
               250            9.62624

OPA627AU-ND      1           19.88
                25           18.55
               100           17.225
               250           16.89376

LM3875TF-ND      1            6.36
                25            5.03
               100            4.0299
               250            3.84812

LM3886TF-ND      1            7.14
                25            5.644
               100            4.522
               250            4.318
======================================

Report message to a moderator

Re: Group Build National Semiconductor amp [message #59411 is a reply to message #59304]

Thu, 18 June 2009 18:11

DanTheMan
Messages: 84
Registered: May 2009

Viscount

Wayne, I've been thinking about the new LM49810 or 11. Acording the the chip designers it's the best sounding one they make. Of course I was just thinking 1 or 2 to hear.

Report message to a moderator

Re: Group Build National Semiconductor amp [message #59414 is a reply to message #59411]

Thu, 18 June 2009 22:43

Wayne Parham
Messages: 18793
Registered: January 2001

Illuminati (33rd Degree)

That might be cool too. Any idea where to buy them? What are they like? I'm at LSAF, so I don't have much time to search around on Google right now.

Report message to a moderator

Re: Group Build National Semiconductor amp [message #59415 is a reply to message #59304]

Fri, 19 June 2009 01:08

DanTheMan
Messages: 84
Registered: May 2009

Viscount

Here' some app notes: http://www.national.com/pf/LM/LME49810.html#General%20Descri ption
http://www.national.com/ds/LM/LME49810.pdf
and:
http://www.national.com/ds/LM/LME49811.pdf

diy audio site has a few threads about it with some of the National engineers discussing their various merits. I know the famed Bob Pease played a significant role in their development.

Report message to a moderator