Replacement for NPD5565?

SQLGuy · 5th February 2009, 12:51 AM

Hi folks,

My PS Audio amp uses NPD5565's for its input section. These are obsolete, but Linear Systems lists their LS844 as a sub. I am not sure if this is correct.

The noise, drift, and matching on the LS844 are certainly better than the NPD5565, but the gain seems much lower. Please let me know if I'm reading the data sheets correctly.

LS844 - Yfs typically 1.5mmho
NPD5565 - Gfs typically 10mmho

Are Yfs and Gfs the same thing? If so, wouldn't there be better subs than the LS844... like maybe the LS5911?

Thanks,
Paul

mtlin12 · 5th February 2009, 02:40 AM

You can try Vishay siliconix 2N5565/5566, the package is hermetically-sealed
TO-71 different from NPD5565's mini-DIP, but I think it still can be pin compatible.

SQLGuy · 5th February 2009, 02:57 AM

I looked at that, but it's a bit pricey... Mouser's the only supplier where I've found them and they want $83 a piece! (no typo on my part... don't know if there's one on Mouser's end).

The funny thing is, if you put in 2N5565 into Linear Systems' cross reference app, they cross it to LS5911. 2N5565 and NPD5565 are the same devices but one is TO-71 and the other is DIP8. Both LS844 and LS5911 are available in both TO-71 and in DIP8.

I had already ordered some LS844's based on Linears' cross ref guide, but I think I'll call them tomorrow to find out what's up here.

Thanks,
Paul

PH104 · 5th February 2009, 03:11 AM

Paul --

How many of the 5565's do you need? I might have a Siliconix or two kicking around if the LS don't work out. I'll check tomorrow.

Phil

SQLGuy · 5th February 2009, 06:48 PM

Well, I checked with Linear Systems, and their initial reaction was that the LS844 was not the best choice to replace an NPD5565. Apparently their cross reference guide has not been updated in a while. With such a difference in gain, I kind of wonder why they ever recommended them, though.

Their recommedation over the phone was their newer LSK389 device. I guess I'll shelve the LS844's until I come up with a project that could use them.

Phil: thanks for the offer. I'm going to try first swapping the existing 5565's to see whether the noise follows the right channel device. I'll let you know.

Cheers,
Paul

5th February 2009, 12:51 AM	#1
SQLGuy diyAudio Member Join Date: Jan 2009	Replacement for NPD5565? Hi folks, My PS Audio amp uses NPD5565's for its input section. These are obsolete, but Linear Systems lists their LS844 as a sub. I am not sure if this is correct. The noise, drift, and matching on the LS844 are certainly better than the NPD5565, but the gain seems much lower. Please let me know if I'm reading the data sheets correctly. LS844 - Yfs typically 1.5mmho NPD5565 - Gfs typically 10mmho Are Yfs and Gfs the same thing? If so, wouldn't there be better subs than the LS844... like maybe the LS5911? Thanks, Paul

5th February 2009, 02:40 AM	#2
mtlin12 diyAudio Member Join Date: Nov 2003 Location: Taipei	You can try Vishay siliconix 2N5565/5566, the package is hermetically-sealed TO-71 different from NPD5565's mini-DIP, but I think it still can be pin compatible. __________________ EuLeit Audio Studio one of the best hi-end Amp design house in Taiwan http://www.euleitaudio.com

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Replacement for CDM 12.1	Sandor	Digital Source	4	12th June 2010 08:01 PM
NPD5565 for PS Audio pre amp	Williams Audio	Solid State	2	9th November 2007 05:39 PM
irf 740 replacement	bob_v5	Solid State	6	10th December 2005 02:16 PM
looking for a replacement for pcb cad	bigpanda	Solid State	1	18th September 2004 07:24 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

5th February 2009, 02:57 AM	#3
SQLGuy diyAudio Member Join Date: Jan 2009	I looked at that, but it's a bit pricey... Mouser's the only supplier where I've found them and they want $83 a piece! (no typo on my part... don't know if there's one on Mouser's end). The funny thing is, if you put in 2N5565 into Linear Systems' cross reference app, they cross it to LS5911. 2N5565 and NPD5565 are the same devices but one is TO-71 and the other is DIP8. Both LS844 and LS5911 are available in both TO-71 and in DIP8. I had already ordered some LS844's based on Linears' cross ref guide, but I think I'll call them tomorrow to find out what's up here. Thanks, Paul

5th February 2009, 03:11 AM	#4
PH104 diyAudio Member Join Date: Nov 2001 Location: New Mexico	Paul -- How many of the 5565's do you need? I might have a Siliconix or two kicking around if the LS don't work out. I'll check tomorrow. Phil

5th February 2009, 06:48 PM	#5
SQLGuy diyAudio Member Join Date: Jan 2009	Well, I checked with Linear Systems, and their initial reaction was that the LS844 was not the best choice to replace an NPD5565. Apparently their cross reference guide has not been updated in a while. With such a difference in gain, I kind of wonder why they ever recommended them, though. Their recommedation over the phone was their newer LSK389 device. I guess I'll shelve the LS844's until I come up with a project that could use them. Phil: thanks for the offer. I'm going to try first swapping the existing 5565's to see whether the noise follows the right channel device. I'll let you know. Cheers, Paul

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)