Scott 299D tubes - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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 19th March 2017, 11:45 AM   #1
diyAudio Member
 
Join Date: Feb 2015
Location: edgewater maryland
Default Scott 299D tubes

Hello to all a while back i repaired and recapped my HH scott 299D with the help of people from the board . Amp sounds fantastic but i am thinking about changing the preamp and output tubes to maybe NOS or good new production tubes. Right now i have Russian EH 7591s and Tungsol reissue 12ax7s and it sounds really good. There are a lot of variables about tubes so any info or suggestions would be great .


Click the image to open in full size.
  Reply With Quote
Old 19th March 2017, 10:21 PM   #2
diyAudio Member
 
Join Date: Apr 2004
Location: Monroe Township, NJ
NOS 7591s are very scarce. Proper matching will be difficult and cost high. Stay with the current production EH stock.

You can experiment with the voicing by using the Sovtek 12AX7LPS in the phono section and "reissue" Mullards in the line section.

Install the series SS diode tweak on the 5AR4 socket and rest easy about using the comparatively inexpensive Sovtek tube. My preference is for UF4007s, instead of the 1N4007s shown in the graphic. It may not matter here, as the vacuum rectifier blocks SS diode noise, but UFnnnn parts generate much less switching noise than the corresponding 1Nnnnn stuff and quiet diodes are the ones to have on hand.
Attached Images
File Type: jpg SS Series Diode Tweak.jpg (106.0 KB, 75 views)
__________________
Eli D.
  Reply With Quote
Old 20th March 2017, 10:50 PM   #3
diyAudio Member
 
Join Date: Feb 2015
Location: edgewater maryland
Thanks for the reply Eli and the info on the tubes . I will install the Diode tweak on the rectifier ( is this mod to prevent the rectifier from arcing ) right now i have a genalex gold lion GZ34 rectifier . But after some research i see that genalex and sovtek are both made by new sensor. Maybe i should at least try to find a NOS rectifier tube . What brand NOS would be worthy . But i will still do the diode mod .
  Reply With Quote
Old 20th March 2017, 11:02 PM   #4
diyAudio Member
 
Join Date: Apr 2004
Location: Monroe Township, NJ
Forget about NOS 5AR4s. Do you really want to pay over $100?

The Sovtek 5AR4 is prone to startup arcing, when used at the top of its documented range. The series SS diodes kill the arcing and do no harm, when a top notch tube is present. Win/win, which is something that does not come along frequently. Other than arcing, the Sovtek tube is quite satisfactory.
__________________
Eli D.
  Reply With Quote
Old 20th March 2017, 11:18 PM   #5
diyAudio Member
 
Join Date: Feb 2015
Location: edgewater maryland
Yes you are right Eli i will do the diode mod and save money for some 12AX7s i could probably get a set of KLH model 6 speakers for the price of the rectifier tube . I will do the mod this week and post a picture i may have the diodes here if not i will have to order them .
  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
Scott 299D chandlerh2 Tubes / Valves 42 4th April 2015 02:15 AM
Scott 299D Calibration A Sound Mind Tubes / Valves 5 17th October 2011 04:00 PM
scott 299D output transformers? iain42 Tubes / Valves 11 20th February 2009 10:58 PM
Best tubes for Scott 222 ihscoutlvr74 Tubes / Valves 0 24th December 2007 06:55 AM


New To Site? Need Help?

All times are GMT. The time now is 09:53 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2
Wiki