Yaqin mc10L - Page 16 - 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 29th January 2012, 04:42 AM   #151
data is offline data  Australia
Account disabled at member's request
 
Join Date: Jul 2007
Location: Brisbane
A 510r 3w resistor is a good value, 270r 2w minimum for strapping. A lot of folk use something like a 100r 1w, but that's not safe as far as I have been taught.

Remove the UL connection and insulate well and tie back in a safe position, sever GNF. I just snipped out the cap & resistor in the GNF line of each channel that live on the pre board.

Last edited by data; 29th January 2012 at 04:44 AM.
  Reply With Quote
Old 29th January 2012, 09:31 PM   #152
diyAudio Member
 
Join Date: Jan 2012
How does the plate resistance of a triode strapped El34 compare to a true triode like the 300B? What sort of damping factor can you maintain with the NF removed? Sorry for the newb q's, I have a 20L and they're somewhat similar. I'm just starting to learn a bit about tube circuits.
  Reply With Quote
Old 29th January 2012, 09:57 PM   #153
data is offline data  Australia
Account disabled at member's request
 
Join Date: Jul 2007
Location: Brisbane
The Yaqin MC-20L is switchable between UL and Triode mode, as you know, whether the switching also switches out the GNF I have no idea, but in such a mode the GNF is not needed, and without it reduces distortion considerably.

Sorry but I'm not sure on the damping factor differences, and haven't the time to look into it, all I know is the MC-10L when triode strapped sounded much cleaner once the GNF was removed.
  Reply With Quote
Old 29th January 2012, 11:33 PM   #154
diyAudio Member
 
Join Date: Jan 2012
I actually never use it in triode mode, ultralinear seems to have a little fuller midrange. Playing around with the GNF sounds interesting, though I am concerned about any impact on the bottom end. This amp is already a bit on the bright side and I'd hate to lose any bass.
  Reply With Quote
Old 30th January 2012, 12:07 AM   #155
frugal-phile(tm)
diyAudio Moderator
 
planet10's Avatar
 
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Blog Entries: 5
Quote:
Originally Posted by rntlee View Post
I actually never use it in triode mode, ultralinear seems to have a little fuller midrange.
Which is better is very speaker dependent

dave
__________________
community sites t-linespeakers.org, frugal-horn.com, frugal-phile.com ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 30th January 2012, 12:48 AM   #156
diyAudio Member
 
Join Date: Jan 2012
I've heard that of SET amps, but not PP, is there a reason? Here's my 20L setup: MS-20L

It's driving Paradigm monitor 7's.
  Reply With Quote
Old 30th January 2012, 12:57 AM   #157
frugal-phile(tm)
diyAudio Moderator
 
planet10's Avatar
 
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Blog Entries: 5
Your speaker has XOs and likely an ugly impedance curve so it will likely be best with Pentode & feedback

dave
__________________
community sites t-linespeakers.org, frugal-horn.com, frugal-phile.com ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 30th January 2012, 03:06 AM   #158
data is offline data  Australia
Account disabled at member's request
 
Join Date: Jul 2007
Location: Brisbane
I wouldn't sever the GFB on that amp unless you fix it in Triode, but you could reduce it, the GNF on the MC-10L was high.

And from what Dave has said about those speakers they are a load , so best to run it as you are in UL. An I see what Dave means, with the curve where the port takes over....

Last edited by data; 30th January 2012 at 03:12 AM.
  Reply With Quote
Old 30th January 2012, 05:12 AM   #159
data is offline data  Australia
Account disabled at member's request
 
Join Date: Jul 2007
Location: Brisbane
Still, a nice speaker all the same.

Many speakers have pretty wild swings much worse than those Paradigm's, and a lot of manufacturers don't publish the real data.
  Reply With Quote
Old 31st January 2012, 11:06 PM   #160
diyAudio Member
 
Join Date: Jan 2012
Did a little more digging about the damping factor of triode strapped El34's and I found an article by Menno Van Der Veen where he listed a comparison of various circuit types using El34's w/o GNF. In ultralinear, the circuit had a DF of 0.315. In triode mode it had a DF of 0.948 (both are w/o GNF). Does a DF of just under one mean the bass will be sloppy? Well, I found another article that compared the bass note decay time between various DF values. The difference in decay between DF>2000 and DF=1 is about 0.03 seconds. 3/100's of a second! I don't think that is even audible...at least not by me. So this has gotten me more interested in removing the GNF from the triode mode on my amp. I think I'll investigate adding a switch to turn off GNF for triode mode.
There were some old amps that had adjustable DF...do you think they did this by varying the GNF? Could one add a pot in place of the resistor to make GNF adjustable?
  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
Help and your input on YAQIN MC10L EL34 kalinga Tubes / Valves 6 27th January 2011 08:39 PM
Yaqin MC10L and KT88 megalodementia Tubes / Valves 21 15th January 2011 01:51 PM
MC10L is good or not iao Tubes / Valves 5 14th August 2010 11:22 AM
Yaqin mc10l "popping" Reg Stir Tubes / Valves 5 5th August 2008 04:43 PM
Yaqin MC-10L cruzrman Tubes / Valves 0 23rd July 2008 02:37 AM


New To Site? Need Help?

All times are GMT. The time now is 01:18 PM.


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