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 February 2013, 03:52 AM   #1
djef is offline djef  United States
diyAudio Member
 
Join Date: Nov 2012
Default Suggest a preamp project for me.

I'm looking to make a preamp from scratch to drive a pair of MC30s. Would anyone have a suggestion for a circuit? I really just need it as a phono pre with maybe some simple tone controls.
  Reply With Quote
Old 27th February 2013, 03:17 PM   #2
diyAudio Member
 
Join Date: Aug 2012
Blog Entries: 1
I built the preamp from DIYaudioprojects.com I used primarily recycled parts, all of which i sourced and soldered together into a nice little line stage. I am very happy with it and I am planning on building the RIAA phono pre from the same designer. If desired, tone controls can be added but I would build it as is and see how you like it first. It uses 12AX7A variants so tubes should be no problem to source or roll. If you are handy at all you can make these little things perform. Hope this helps.
  Reply With Quote
Old 27th February 2013, 05:34 PM   #3
diyAudio Member
 
Miguel Lopez's Avatar
 
Join Date: Feb 2012
Location: Havana, Cuba
Have you tried with the pre-amplifier of the Mullard 5-10 design?

Click the image to open in full size.

Mullard 5-10. Ten Watt Amplifier
  Reply With Quote
Old 27th February 2013, 07:37 PM   #4
evanc is offline evanc  United States
diyAudio Member
 
Join Date: Sep 2009
Location: New Jersey. About 1 hour from NYC and 1 min. from the beach
My first decent system had a pair of mc30s. For me they had plenty of power with just a passive preamp. Maybe just build a phono preamp and box it with an attenuator and an input selector. Check out the Simplistic njfet riaa by salas.

Evan
__________________
http://www.evancotler.com
  Reply With Quote
Old 28th February 2013, 02:30 AM   #5
djef is offline djef  United States
diyAudio Member
 
Join Date: Nov 2012
Quote:
Originally Posted by Miguel Lopez View Post
Have you tried with the pre-amplifier of the Mullard 5-10 design?

Click the image to open in full size.

Mullard 5-10. Ten Watt Amplifier
This looks like great project. I might do this. This is for my phono setup however. Will I need to incorporate RIAA circuitry somehow?
  Reply With Quote
Old 28th February 2013, 03:47 AM   #6
diyAudio Member
 
Chris Hornbeck's Avatar
 
Join Date: May 2011
Location: Little Rock
The Mullard is certainly classic, but not really a preamp in the modern sense of the term. It's from the days of ceramic phono cartridges, crystal AM tuners, and a very high required sensitivity. Today a preamp, for those who still spin wax, has two parts, a phono equalizer (that brings the tiny output from a modern phono cartridge up to line levels) and a line stage (that selects between various line level sources, has gain control and sometimes tone controls, and usually has some flat gain of its own, maybe 10 or 20 dB).

For DIY and especially for a first project, these might be considered to be two separate gigs. As has already been suggested, the line stage might be made "passive", without a gain stage, just to get your feet wet, leaving room to add the gain if desired later. The MC30 has a high sensitivity, so is a good candidate for this.

A good phono stage is much more difficult to get right, so might be saved for later. Just some thoughts.

All good fortune,
Chris
  Reply With Quote
Old 11th May 2013, 09:23 PM   #7
diyAudio Moderator Emeritus
 
Bas Horneman's Avatar
 
Join Date: Apr 2002
Location: The Netherlands
Blog Entries: 18
Trafomatic phono reference one apparently is wonderful. One of my next projects. Schematic on sixmoons.

Sent from my GT-N7000 using Tapatalk 2
  Reply With Quote
Old 11th May 2013, 10:23 PM   #8
diyAudio Member
 
Soonerorlater's Avatar
 
Join Date: Jul 2008
Location: Belfast
As a starter I'm thinking of building Eli Duttmans' version of the RCA phono schematic.
Full_Tweaked_RCA_Phono_Stage10.jpg
__________________
When white moths were on the wing,
And moth-like stars were flickering out,

Last edited by Soonerorlater; 11th May 2013 at 10:26 PM.
  Reply With Quote
Old 12th May 2013, 02:10 AM   #9
diyAudio Member
 
Join Date: Apr 2004
Location: Monroe Township, NJ
A phono preamp is not a simple project. Definitely look before you leap.

JMO, the tweaked RCA setup is good, without being highly complicated. Those folks who've built the setup are happy. I've uploaded a graphic for a cost effective PSU that's quite suitable.

Contact member Jeff Yourison to obtain the benefit of his construction experience.
Attached Images
File Type: gif RCA_Hybrid_phonostage_PS2.gif (110.4 KB, 101 views)
__________________
Eli D.
  Reply With Quote
Old 12th May 2013, 09:21 AM   #10
mach1 is offline mach1  Australia
diyAudio Member
 
mach1's Avatar
 
Join Date: Sep 2004
Location: Brisvegas
Quote:
. Trafomatic phono reference one apparently is wonderful. One of my next projects. Schematic on sixmoons.
I wonder why the designer uses parallel resistors everywhere, with 4 on the 6N6P cathodes?
__________________
Au rutti wop-bop-a-loom-bop-a-boom-bam-boom - Richard Penniman
  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
Suggest me a preamp for my F4! giacomo_pagani Pass Labs 163 6th March 2011 10:41 AM
pls suggest a project lordearl Tubes / Valves 7 22nd March 2010 02:55 PM
suggest about 9002/vt202 preamp please jp74 Tubes / Valves 0 1st June 2009 07:17 AM
Preamp suggest, please. kacernator Tubes / Valves 18 27th February 2008 07:29 PM
Please suggest a preamp HiFiNutNut Solid State 5 28th May 2004 06:08 PM


New To Site? Need Help?

All times are GMT. The time now is 11:18 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