type 27 pre - Page 2 - 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 16th December 2003, 09:35 AM   #11
exurbia is offline exurbia  Australia
diyAudio Member
 
exurbia's Avatar
 
Join Date: Jul 2002
Location: Perth
I knocked together the 27 pre last weekend. The sound is amazing i'll never go back to my accuphase pre, althouth the accuphase does have better facilities
I am using my power supply chokes in the anode feed, these are 450H. I want to go back to a valve rectifier using 5u4g, as i have a few. The problem is i no longer have the chokes, can i use a capacitor filter and if so is there a simple way to work out the required C and R.
thanks in advance, peter.
  Reply With Quote
Old 22nd December 2003, 03:21 PM   #12
diyAudio Member
 
Join Date: Nov 2002
Peter

I suggest you put the chokes back in the power supply and purchase several plate resistors and see if you can detect a difference. I have done this and I like the #27 with plate resistors as opposed to plate chokes. Just my .02

J
  Reply With Quote
Old 22nd December 2003, 04:38 PM   #13
exurbia is offline exurbia  Australia
diyAudio Member
 
exurbia's Avatar
 
Join Date: Jul 2002
Location: Perth
Gday J,

Thanks for your advice, i had already given up on the chokes they are back in my supply. I'm currently using 130R on the anode, I hate to say this, the tube type decides which resistance should be used. I have some deforest 427 with the punched shiny anode and a nipple on top. these run with 130, the 427's with the mesh anode run 150. I have lots of other 27's to try and it is quite a task.
  Reply With Quote
Old 23rd December 2003, 11:49 AM   #14
diyAudio Member
 
Join Date: Nov 2002
Peter

I'm using 50K plate resistors and have 180volts on the plate and 12volts across the cathode resistor and it sounds every bit as good as the #26 did.

J
  Reply With Quote
Old 26th December 2003, 05:01 PM   #15
stigla is offline stigla  Norway
diyAudio Member
 
Join Date: Nov 2001
Location: Trondheim
Hi!

I am currently building a #27 pre for my brother. It will be loaded by Gary Pimms BBMCCCS, using the mu output.

Check out http://www.angelfire.com/ut/Likkhalt/index3.htm

to see schematic plus construction pic's so far.

I really look foreward to listen to this pre, I think it will be a stunner!! The tubes will be AC heated, so I hope I dont runn into problems with hum. I'll keep you posted about the sound when I get it running.

stigla
  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
Another X-type Amp vdi_nenna Solid State 8 17th September 2008 09:58 PM
What type of CAP? Gophat Car Audio 4 28th April 2008 04:14 PM
different type of TVC? jesserparker Chip Amps 1 25th March 2008 04:25 PM
Re : BL type & GR type of transistor for Aleph-Ono Arion Pass Labs 4 29th January 2007 07:15 PM


New To Site? Need Help?

All times are GMT. The time now is 10:29 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