nice looking 5u4g from EML in SSE? - diyAudio
Go Back   Home > Forums > Commercial Sector > Vendor Forums > Tubelab

Tubelab Discussion and support of Tubelab products, prototypes and experiments

Reply
 
Thread Tools Search this Thread
Old 20th February 2010, 11:59 AM   #1
dubdub is offline dubdub  United Kingdom
diyAudio Member
 
Join Date: Jan 2008
Default nice looking 5u4g from EML in SSE?

Hi All,


Well my Simple SE has been running for 12 months now and all is good and sounds great ( edcor power tranf 375-0-375 @ 175mA, transendars OPT +6550s tubes +obbigato oil 70uf oil cap) but I want to try out a few different tweaks/tubes.

I've come across this nice looking tube 5u4g from Emission Labs and I have read on the forum that 5u4gs have been used in simple SEs - any ideas or thoughts if it would be practicable to use this tube ?


5U4G Data sheet. Emission Labs.

Cheers for any advice
  Reply With Quote
Old 20th February 2010, 05:06 PM   #2
rknize is offline rknize  United States
diyAudio Member
 
rknize's Avatar
 
Join Date: Feb 2009
Location: Chicagoland
Send a message via AIM to rknize Send a message via Yahoo to rknize
The 5U4 requires 3A from the 5V winding (the 5AR4 only needs 2A). As long as your power transformer can handle that, then it will be fine. Expect a lower B+ voltage with any of the 5U4 types...30-40V lower.
  Reply With Quote
Old 21st February 2010, 01:59 AM   #3
diyAudio Member
 
tubelab.com's Avatar
 
Join Date: Jul 2005
Location: West Virginia panhandle
Note the absolute maximum input capacitor value is 33uF. The standard input capacitor in the Simple SE is 47uF. Their required transformer resistance is higher than a 5AR4, it is likely that your Edcor has a lower resistance than their recommended values. At a minimum I would add an inrush current limiter in series with the power transformer center tap and reduce the value of the input cap. The Simple SE runs a 5AR4 pretty close to the maximum peak current. EML tubes aren't cheap, and I don't see a peak current rating in their data.
__________________
Too much power is almost enough! Turn it up till it explodes - then back up just a little.
  Reply With Quote
Old 22nd February 2010, 10:21 PM   #4
dubdub is offline dubdub  United Kingdom
diyAudio Member
 
Join Date: Jan 2008
Hi all

Thanks for the advice- I would have considered changing c1 to a smaller value but anything else Im not too sure now- all I'll end up doing is destroying a nice looking/ expensive tube! it would of made me laugh for about a minute then it would sink in ....very slowly...all that money gone up in sparks -damn!

Still Im going to look around for some nice rectifiers to experiment with (maybe nos?) any recomendations of types that could just drop in are much appreciated- thanks again

Last edited by dubdub; 22nd February 2010 at 10:32 PM.
  Reply With Quote
Old 22nd February 2010, 10:28 PM   #5
dubdub is offline dubdub  United Kingdom
diyAudio Member
 
Join Date: Jan 2008
just come across an interesting explanation from George tubelab on rectifiers and c1 value cap

Simple Simple SE questions


"Here is my real (overly) simple explanation:

The rectifier tube supplies the power for the entire amplifier. In the Simple SE this means that one tube must pass enough current to feed four tubes, so it has a tough job.

The filter capacitors store a reserve supply of energy to feed these four hungry tubes during times when they want more than the rectifier tube can deliver. They are completely empty when the amp is switched on. The amplifier tubes don't get to eat until the resovoir is full.

Now, upon flipping the power switch the four amplifier tubes get their wake up call, and can sit at the table awaiting the rectifier tube to feed them their breakfast.

The rectifier tube is slapped out of bed, told to immediately begin filling the resovoir before it is awake yet (cathode warmed up) so that the amplifier tubes can have their breakfast. If the resovior (first cap) is too big, the rectifier tube will have a heart attack before it can fill it!

OK, overly simple somewhat stupid explanation, but that is what happens. The rectifier tubes made today seem to be of a lesser quality than those made in the past. If the coating on the cathode is not of a uniform thickness, and the plate to cathode spacing is not constant, the problem is worse.

The rectifier tube must begin to pass current as it is warming up. If the spacing inside the tube is not uniform the current will flow in one localized area, leading to fireworks inside the tube. For this reason the first cap (C1) should be kept as small as possible. If a choke will be used, a 33, or 39 uF cap might be a better choice than a 47 uF."

Last edited by dubdub; 22nd February 2010 at 10:33 PM.
  Reply With Quote
Old 23rd February 2010, 08:46 AM   #6
urmoo is offline urmoo  Estonia
diyAudio Member
 
urmoo's Avatar
 
Join Date: Sep 2009
Location: Estonia
Quote:
Originally Posted by dubdub View Post
Still Im going to look around for some nice rectifiers to experiment with (maybe nos?) any recomendations of types that could just drop in are much appreciated- thanks again
What about some russian NOS tubes? Just one problem- they are directly heated tubes and its better to have an STB switch. Price is around 2-6$ each. http://www.cqham.ru/tubes/soviet/scan/5z3s.gif

Click the image to open in full size.

Click the image to open in full size.

Last edited by urmoo; 23rd February 2010 at 08:50 AM.
  Reply With Quote
Old 13th March 2010, 09:23 PM   #7
dubdub is offline dubdub  United Kingdom
diyAudio Member
 
Join Date: Jan 2008
Urmoo thanks for the tip! Well I got some russian NOS and very impressed! sound is more crisper/cleaner (but slightly less bass but still good)- early days though=Very nice tube that Im trying with a pair of 6p3c...will load some pics up
  Reply With Quote
Old 15th March 2010, 12:39 AM   #8
dubdub is offline dubdub  United Kingdom
diyAudio Member
 
Join Date: Jan 2008
thanks everyone for the tips-very happy with this valve- good stuff!

Click the image to open in full size.
Click the image to open in full size.
  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
EML 300B XLS and Mesh comparison ReinoutdV Tubes / Valves 15 5th November 2009 05:05 PM
5u4g input capacitor alexg Tubes / Valves 4 4th June 2009 05:33 AM
eml 520 v2 info vitalstates Tubes / Valves 2 4th December 2006 10:47 AM
For Sale:EML 45 Solid Plate Matched Pair DeonG Swap Meet 0 21st March 2006 07:35 PM
5u4g vs 5u4gb tenderland Tubes / Valves 3 28th April 2005 07:58 AM


New To Site? Need Help?

All times are GMT. The time now is 11:44 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