Any experiences with AD8671/2/4? - 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 15th January 2004, 11:31 AM   #1
diyAudio Member
 
Popolvár's Avatar
 
Join Date: May 2002
Location: Piestany, Slovakia
Default Any experiences with AD8671/2/4?

Does anyone have some experiences with AD8671?

It seems to be a good replacement for (used to be) popular NE5534/5532. Ad 8671 has very low noise, low THD, high PSRR, it is unity gain stable... Drawbacks are that it is available just in SMD package and that in comparison with other adored opamps such OPA627, AD825, AD8065, ... it is quite slow - 4V/us. I plan to use it in active xover.

More info:
AD8671: http://www.analog.com/Analog_Root/pr...8671%2C00.html
AD8672: http://www.analog.com/Analog_Root/pr...8672%2C00.html
AD8674: http://www.analog.com/Analog_Root/pr...8674%2C00.html

Thanks

Daniel
  Reply With Quote
Old 15th January 2004, 02:09 PM   #2
PMA is offline PMA  Europe
diyAudio Member
 
PMA's Avatar
 
Join Date: Apr 2002
Location: Prague
Hi Dano,

I would prefer circuits with higher slew rate.

Pavel

P.S. At zije cesko-slovenska komunikacia! /in czech and slovak /
  Reply With Quote
Old 15th January 2004, 02:29 PM   #3
diyAudio Member
 
Popolvár's Avatar
 
Join Date: May 2002
Location: Piestany, Slovakia
Quote:
Originally posted by PMA
I would prefer circuits with higher slew rate.
OK, so what else suitable do we have for active xover? I would prefer low noise, "normal price" (no OPA627) and dual/quad packages. I remember some opamp data measurements provided by BigBobo and the result was NE5532. I would like to use something newer ;-) but I do not want "nice"/colored sound. What are other possibilities? AD8066?

Quote:
Originally posted by PMA
P.S. At zije cesko-slovenska komunikacia! /in czech and slovak /
and also in English
  Reply With Quote
Old 15th January 2004, 02:55 PM   #4
PMA is offline PMA  Europe
diyAudio Member
 
PMA's Avatar
 
Join Date: Apr 2002
Location: Prague
I am pretty sure that AD8066 is a perfect device.
And you could give a try to AD8620.
  Reply With Quote
Old 16th January 2004, 07:08 AM   #5
diyAudio Member
 
Popolvár's Avatar
 
Join Date: May 2002
Location: Piestany, Slovakia
Default AD8610/8620

Quote:
Originally posted by PMA
I am pretty sure that AD8066 is a perfect device.
And you could give a try to AD8620.
Thanks, I have printed out datasheets for AD8671, AD8065, AD8610 and have read them last evening. AD8610 looks quite promissing, it seems to be "creme de la creme" of AD opamps. I was afraid how much will it cost but have found that it should be about three times cheaper than OPA627 so I could breathe it out. (Though AD8065 is again about three times cheaper than AD8610). Same should probably apply also to dual packages.

I will definitely check the price at our local AD distributor.

Daniel
  Reply With Quote
Old 25th February 2004, 06:05 AM   #6
jcx is online now jcx  United States
diyAudio Member
 
Join Date: Feb 2003
Location: ..
AD8671 low noise 10 MHz Fet input op amp http://www.analog.com (type ad8671 into the search box yourselves, it will be good practice for some of you)

The data sheet specs look really good – if anything Analog’s marketing people may have missed just how significant an advance this represents in low frequency low noise performance in monolithic Fet input op amps

The low frequency noise #s given are ~ 5x better than the AD743 and the max/typ spec #s for low frequency noise is incredibly tight at 1.3x

3x lower input C and 3-10x higher cmrr suggests that cm current induced distortion with higher (unbalanced) source impedance is also going to be superior

the quad device makes paralleling the 4 op amps for ˝ the noise very attractive – the low 1/f corner makes this actually useful over nearly the entire audio range where other fet op amps fail to show useful improvement due to 1/f corner frequencies nearing 1KHz

the audio THD distortion graph looks good @ 0.0006% into 600 Ohms and the flatness of the graph may actually evidence of poor measurement technique – the distortion should continue to decrease with lower frequency until it meets the noise floor

the slew rate is less than impressive at 4 V/us but adequate for most audio applications

it is likely the best use of the AD8671 will be in composite op amp arrangements where the low noise of the AD8671 is combined with a high output current high bandwidth output op amp in a common feedback loop – relieving the AD8671 of large slew requirement

a single AD8671 should make an excellent mm phono preamp front end, the paralleled quad could be good with mc cartridges or ribbon mics

(no you can’t just solder all the like pins together but you can sum the outputs of multiple individual op amp feedback amplifiers which are amplifying a common input signal)

no i'm not being paid by AD but if they just happen to add a few extras to my sample request i won't complain
  Reply With Quote
Old 25th October 2007, 03:37 AM   #7
Ryssen is offline Ryssen  Sweden
diyAudio Member
 
Ryssen's Avatar
 
Join Date: Dec 2003
Location: Sweden--> Here
An old thread,but I tried AD8671 in my headphone amp,and it beat LM4562 !!Much more natural...
Any one else tested this one?
__________________
Regards Ĺke
  Reply With Quote
Old 23rd December 2011, 02:29 AM   #8
gvelim is offline gvelim  United Kingdom
diyAudio Member
 
Join Date: Jun 2007
Default C

I have just looked at the AD8672 specs for my DacMagic dac stage modification.

This is to replace a LME49720 that poses as a Differential multipolar bessel filter at the DAC's output - Wolfson DAC is operating in dual differential mode.

the goal is for the AD8672 to drive the XLR output + RCA stage. The RCA stage is currently running with a LME49720. Would this benefit from 8672 too or better use something like OPA1612 ?
  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
P3B experiences? Colescuttle Solid State 7 12th May 2011 12:23 AM
OP AMP EXPERIENCES and HOW TO tawn10 Analog Line Level 59 5th June 2007 04:14 AM
Experiences with ClarityCaps: audioangel9 Multi-Way 2 27th May 2007 09:47 PM
Experiences With F200A? was ist los? Multi-Way 1 27th July 2004 08:33 AM
Experiences with www.theloudspeakerkit.com barts Multi-Way 11 28th February 2003 09:09 AM


New To Site? Need Help?

All times are GMT. The time now is 09:04 PM.


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