Replica Pre QUAD 22 - Questions on mids - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

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 27th January 2006, 12:48 PM   #1
Scabiko is offline Scabiko  Argentina
diyAudio Member
 
Join Date: Jul 2005
Location: City of Buenos Aires
Default Replica Pre QUAD 22 - Questions on mids

Hi,

I just replicated a simplified circuit of preamp 22 of Quad, added a PSU and used on the audio signal path caps of 4.4uf (instead of only 2.2 uf) and of 0.47 uf. The pre seems to lack of mids. Modifiying the value of 0.47 uf to a lesser value would increase mid presentation? the 2.2uf cap, has any effect on mids? are there any other mods or changes to improve midīs definition?
Thank you for your time and consideration. Sebastian
  Reply With Quote
Old 27th January 2006, 01:03 PM   #2
nafunga is offline nafunga  United Kingdom
diyAudio Member
 
Join Date: Jul 2005
Location: Whitstable , Kent. UK
Hi,
Are you sure you'r talking about the Quad 22? Coupling caps are around 0.1uf or less on this model, not 2.2uf or 4.7uf.. Is this a transistor amp? I've done quite a bit of work on 22's over the years so am reasonably familiar with the circuitry.

Kind regards,

David..
  Reply With Quote
Old 27th January 2006, 01:28 PM   #3
Scabiko is offline Scabiko  Argentina
diyAudio Member
 
Join Date: Jul 2005
Location: City of Buenos Aires
Thanks for your reply. I am trying to transmit to you what the tecnitian who made it for me told me. Unfortunately, he does not speak English. I will reconfirm with him and get back. I can tell you that on signal path I have 0.47 evox rifa caps (metallized polypropilene) and the cap of 4.4uf was put instead to the electrolityc cap of 25 uf included in the original plan. I really donīt know the importance of the 25 uf cap on the signal.

Please note that we did not put tone controls and from the 0.47 uf signal cap goes straight to the output (passing through certain resistors). We omitted a cap of 0.5 uf that goes before the tone controls on the original plan.

Best ragdrs, Sebastian
  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
Audiomeca TT Replica Jean-Paul_2 Analogue Source 4 15th October 2008 11:22 PM
Some Quad els57 questions! - Novice Questions! Fanuc Planars & Exotics 13 5th December 2007 09:26 AM
Seas Excel mids vs. dayton rs mids in dipole sqlkev Multi-Way 2 10th July 2006 06:28 PM
Kt66 Gec Replica jacquesF77 Tubes / Valves 12 12th March 2005 09:03 AM
(Attn Planet 10!) active xo & 2.5 way back to back Vifa P13 mids - questions paulspencer Multi-Way 9 15th August 2004 05:34 AM


New To Site? Need Help?

All times are GMT. The time now is 10:46 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright Đ1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2