Ad8099 - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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
Reply
 
Thread Tools Search this Thread
Old 16th February 2004, 07:03 PM   #1
audioPT is offline audioPT  Portugal
diyAudio Member
 
Join Date: Aug 2002
Location: Right here
Default Ad8099

Check this link or this (PDF)

I've just received the Sollutions Bulletin from Analog Devices and I wonder if this is a good opamp to make a RIAA preamp.

Regards

Pedro Martins
  Reply With Quote
Old 17th February 2004, 02:34 AM   #2
jcx is online now jcx  United States
diyAudio Member
 
Join Date: Feb 2003
Location: ..
no, not as the input stage - the advertised 1 nV/rtHz low noise only applies over 100KHz

the noise graphs show a typical device with 1/f noise corner at 10KHz and huge current noise, you will need less than 100 Ohm source for the voltage noise spec to apply

there has been little innovation in low noise audio frequency op amps, as far as i know the AD743/745 still lead in the fet category (which would be suitable for mm cartridges) and AD797/LT1028 are the bipolar op amp noise leaders

you can find some discrete fet input designs using japanese fets with ~1 nV/rtHz Vn specs but you might have to select for low 1/f noise yourself
  Reply With Quote
Old 17th February 2004, 07:37 AM   #3
Electrons are yellow and more is better!
diyAudio Member
 
peranders's Avatar
 
Join Date: Apr 2002
Location: Göteborg, Sweden
Blog Entries: 4
If you are after good opamps for RIAA amps, these are OK:

LT1028, LT1115, AD797, NE5534 (low cost) and a couple more.
__________________
/Per-Anders (my first name) or P-A as my friends call me
Super Regulator SSR03 Group buy. Still time for signing up.
  Reply With Quote
Old 17th February 2004, 09:02 AM   #4
audioPT is offline audioPT  Portugal
diyAudio Member
 
Join Date: Aug 2002
Location: Right here
jcx and peranders,

Thanks for the replys.

Yes I know that the LT's and the 'excellent' NE5534 are the best ones in low noise (peranders, let me guess: you are a devoted of the NE5534?? As I am???).

About the noise of the new AD, I've been reading more carefully the specs and I've found that the LT's and NE5534 have better noise figures.

You know, I'm portuguese and still have some difficulties in reading some technical things
  Reply With Quote
Old 17th February 2004, 08:16 PM   #5
diyAudio Member
 
Join Date: Mar 2003
Location: Denmark, Copenhagen
Tjek this out for AD8099:

New ultralow noise, high BW op-amp from ADI

- Ask
  Reply With Quote
Old 17th February 2004, 08:30 PM   #6
diyAudio Moderator Emeritus
 
jean-paul's Avatar
 
Join Date: Sep 2002
Location: Germany
NE5534 has excellent noise figures and that makes it one of the best opamps specwise. There are not much opamps out there that beat NE5534 in that aspect. If noise is your concern you can skip trying most other opamps.

However if you like listening to music instead of more or less noise there are some other choices that maybe are less in specs but sound a lot better.

BTW layout will be very critical with a 550 MHz opamp like AD8099, ADI did not change the pinout for nothing. There is a chance that the preamp will be a RF transmitter ...
__________________
It's only audio. Official member of the Norske Brillegeit Gang.
  Reply With Quote
Old 17th February 2004, 08:39 PM   #7
audioPT is offline audioPT  Portugal
diyAudio Member
 
Join Date: Aug 2002
Location: Right here
jean-paul,

NE5534, I have more than 100 in my stock

About the pcb design, the AD8099 has one innovation: check the pinout. It has a feedback pin that helps making the pcb easier.
Attached Images
File Type: jpg ad8099.jpg (13.6 KB, 235 views)
  Reply With Quote
Old 17th February 2004, 09:00 PM   #8
diyAudio Moderator Emeritus
 
jean-paul's Avatar
 
Join Date: Sep 2002
Location: Germany
Quote:
NE5534, I have more than 100 in my stock
Hi Rick PT, now just imagine that would be 100 pieces OPA627BP and you just got the bill


I am a subsciber to ADI Solutions Bulletin and I was intrigued by AD8099 too. A pity that it is not made in DIL form but I guess in DIL it would not have the specs it has now. It seems that its specs are somewhat over the top for audio-purposes though
__________________
It's only audio. Official member of the Norske Brillegeit Gang.
  Reply With Quote
Old 17th February 2004, 09:33 PM   #9
audioPT is offline audioPT  Portugal
diyAudio Member
 
Join Date: Aug 2002
Location: Right here
Quote:
Originally posted by jean-paul


Hi Rick PT, now just imagine that would be 100 pieces OPA627BP and you just got the bill


He! He!

I know I'm portuguese...
I also know RickPT...
But... I'm audioPT!

Yes... I've spent about 20€ on those NE's... AAbout OPA's... maybe more than 200€

Regards

Pedro Martins
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
AD8099 any good? borges Solid State 0 23rd January 2004 07:16 AM


New To Site? Need Help?

All times are GMT. The time now is 07:43 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2