Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Analog Line Level Preamplifiers , Passive Pre-amps, Crossovers, etc.

Rod Eliot project 88 question
Rod Eliot project 88 question
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 2nd March 2003, 12:55 PM   #11
supernet is offline supernet  Europe
diyAudio Member
 
supernet's Avatar
 
Join Date: Dec 2001
Location: Europe
Me too!

superx98@hotmail.com

Thanks
  Reply With Quote
Old 2nd March 2003, 03:25 PM   #12
trwh is offline trwh  United Kingdom
diyAudio Member
 
trwh's Avatar
 
Join Date: Apr 2002
Location: UK
Hi

I've had about a dozen requests for the schematic of the remote control circuit since I made my original post. I always have to decline, since:

a) The circuit isn't mine, it is from a commercial product, albeit an old one.

b) Even if I did give you the schematic you would need the PIC, which is hard (if not impossible) to get hold of.

I don't know why there isn't a readily available remote control kit for motorised pots out there - if someone were to make one, I'm sure there would be a lot of interest.

See ya,
Tim.
  Reply With Quote
Old 2nd March 2003, 03:27 PM   #13
trwh is offline trwh  United Kingdom
diyAudio Member
 
trwh's Avatar
 
Join Date: Apr 2002
Location: UK
Oh, and c) The PIC is programmed to work with Arcam handsets, which is why I chose the circuit in the first place.
  Reply With Quote
Old 2nd March 2003, 08:56 PM   #14
Mark25 is offline Mark25  United Kingdom
diyAudio Member
 
Mark25's Avatar
 
Join Date: Feb 2002
Location: The Netherlands (Friesland)
here is a pre with different op amps and no cap's, it's from the AA bellini pre, which receives good press.

http://www.pi.infn.it/%7Efederico/bellini.htm

i built the one from the puccini (with caps) and was VERY pleased with the results with my p3a.
Mark
  Reply With Quote
Old 7th August 2003, 03:24 PM   #15
halojoy is offline halojoy  Sweden
On Hiatus
 
Join Date: Nov 2002
Default Re: Re: Rod Eliot project 88 question

Quote:
Originally posted by halojoy

How about some information about what
ESP Project 88 is?

High Quality Audio Preamp (Mk II) - Rod Elliott (ESP)


------------------------------
It is a control preamp based on Burr-Brown OPA2134 dual OP.

Uses one OP for input and a second OP for output.
In between are Balance and Volume control.
It uses input and output caps.
You can select the gain of OPamp to suit your needs.
There are tables for how to Set the Gains of the OPamps.
Suggested Power Supply is 2x15VDC.
--------------------------------------------
Preliminary measurments, on the workbench:

Frequency Response 10 Hz to 250 kHz -0.4 dB
Noise < 0.5 mV RMS at full gain (input open)
Crosstalk Better than -58 dB at 100 kHz
--------------------------------------------
An externally hosted image should be here but it no longer works. Please upload images instead of linking to them to prevent this.

Picture shows the Project 88; OPA2134 hifi pre amp
on the available PCB.


/halo
As rode - Rod Elliot has joined as one member by many at this site,
I'd like to say a welcome, afterwards.
The circumstances could have been better at his arrival.

The number of newbies, who has, through him, gotten a fair introduction
to the hobby of Audio Electronics, can be counted in 1000s
if not 100.000s.

There is often some stuff at his site we can refer and link to,
when somebody asks question, or want a circuit to build.
And so has halojoy done on many occations, for sure.

As I am not know for caressing ANY authority unnessesarely,
I say:
Welcome, but don't expect any other favours,
than ordinary members or Nelson Pass gets.
I will try to superwise that the moderators
keeps everything fair and square.

halojoy has one time said:
The higher you sit, the harder you hit
the ground at your fall


************************************************** ****************

In this thread we find a good example of what can be built
inspired by "Aussie-Rod":

"Project 88; OPA2134 hifi pre amp"

and in this thread with GREAT PICTURES
http://www.diyaudio.com/forums/showt...&threadid=9228

we see how it can combined with
"A double barrelled Elliott P3A Power Amp"


All these "great men" seems to be very busy
but I hope you can contribute every now and then, Rod.
Who would be more suited to comment on your projects?

halojoy - thinks rode's site is like "having circuits in the bank"
  Reply With Quote
Old 24th July 2018, 11:24 AM   #16
Mixi is offline Mixi  Europe
diyAudio Member
 
Join Date: Mar 2017
Location: Vienna
let's bring this thread back to life. i know tons of people know the esp site and recommend reading the articles on it. yet i barely find any information on people building the projects. i read through project 88 and it seems like a fine preamp. yet the last entry in this thread is from 2003 - holy cow, that's 15 years ago.

what's the current opinion on this preamp design?
  Reply With Quote
Old 24th July 2018, 09:52 PM   #17
Mixi is offline Mixi  Europe
diyAudio Member
 
Join Date: Mar 2017
Location: Vienna
guess it's not so popular. i wonder why. the design seems to be sound, low parts counts, well documented ....
  Reply With Quote
Old 24th July 2018, 11:00 PM   #18
jaycee is offline jaycee  United Kingdom
diyAudio Member
 
Join Date: Apr 2004
Location: Norwich, UK
Having built one myself many years ago I can say it performs extremely well
  Reply With Quote
Old 24th July 2018, 11:47 PM   #19
Dirttracker73 is offline Dirttracker73  United States
diyAudio Member
 
Join Date: Jun 2010
Location: Rural, NY
Default P88

I have built two p88 preamps on strip-board. Very simple opamp implementation that sounds totally clear and provides volume and balance controls. I have tried several opamps including OPA2134, TL072, 4558, 4560, 4580, LM833, 2068, 5532, and MC33078. All except OPA2134 and TL072 have volume pot noise. Some are extremely noisey with low frequency (DC) effects and visible speaker cone excursion when turning the volume pot. Definitely needs a capacitor between the balance and volume pots if using bjt opamps. I can't hear any difference between OPA2134 abd TL072, both sound great. Just my $.02
  Reply With Quote
Old 25th July 2018, 12:53 AM   #20
jaycee is offline jaycee  United Kingdom
diyAudio Member
 
Join Date: Apr 2004
Location: Norwich, UK
Yep with BJT opamps there will be DC on the pot tracks and that will make it scratch
  Reply With Quote

Reply


Rod Eliot project 88 questionHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Welcome Jeff and Eliot Face Vendor's Bazaar 0 22nd August 2009 11:21 PM
MJK Project 5 question skrstic Full Range 5 19th March 2008 04:54 PM
Eliot Sound p3a oscillation ray_jay Solid State 16 17th October 2006 12:27 AM
old speaker question, bullet midrange question & link to speaker project wallijonn Multi-Way 10 5th November 2002 07:03 AM
Question about my first DIY project. prash Multi-Way 29 22nd October 2002 06:09 PM


New To Site? Need Help?

All times are GMT. The time now is 01:45 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki