Help needed with 10M45S integration . - 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 28th February 2009, 04:38 PM   #1
diyAudio Member
 
Join Date: Jun 2003
Location: Portugal
Default Help needed with 10M45S integration .

Dear Diy friends , i have joined a 10M45S chip here just as shown at this schematic:
Click the image to open in full size.

I like the sonic result but i am questioning myself , what is happenning with current values now . I have set a 300R resistor for 10 ma at K and 1K resistor between G and K . I haven' t measured the miliamps output until now , but for sure something must be done to restore current levels feeding a 6C45pi (WE437A) equiv.
Please give me advice .

tt
  Reply With Quote
Old 28th February 2009, 06:12 PM   #2
diyAudio Member
 
Join Date: Jun 2008
If I understand your question right . . . .
By increasing the current through the 437a you are changing the voltages at the divider upstream. You either need to take a look at the entire input/driver section and supply to see if you need to re-spec' or redesign it, or return the 437a to it's designed for Ip of 6.5mA.
For the design plate current of .0065A change the set resistor to a 470 (465.38) Ohm on the IXYS chip and get rid of the 1K as well as the original 10K plate load resistor. (You don't need to take it out to try. You can just bypass it with wire) You can put a resistor on the output (the 1K) for a buffer at rf if you need it but to start it's best to keep it simple.
  Reply With Quote
Old 28th February 2009, 06:42 PM   #3
diyAudio Member
 
Join Date: Jun 2003
Location: Portugal
Thanks Hearinspace . I will bypass the 10k resistor and change 300r for 470r . As for the 1k between G and K i have tried it without and the bass had become not so good as it were . Tubelab says it prevent oscilation .
Do you think the reg will present 10ma at output K regardless it has 6.5ma at input A, just because i set 300R at K for 10ma regulation ?
  Reply With Quote
Old 1st March 2009, 12:32 AM   #4
diyAudio Member
 
Join Date: Jun 2008
Your high voltage (B+) connects to the centre pin A. The Bias resistor (470 Ohm) is across pins G & K (1 & 3). The output is taken from G (pin 1). The bias resistor is what controls the current that the 10M45S can pass. The ~470 Ohm value sets the current at ~6.5mA. As it is being used as a two terminal device (ie. only two interface connections with the rest of the circuit) there is only one possibility - what goes in must come out (and vice versa) so if 6.5mA is coming out , 6.5mA is going in.

As always . . . Safety First!!! You do know the rules for safe testing etc. right?
  Reply With Quote
Old 1st March 2009, 03:12 PM   #5
diyAudio Member
 
Join Date: Jun 2003
Location: Portugal
Please have a look at datasheet Fig 1 and 2 ., if i understand it correctly it doesn't match what you say . Sorry cannot attach it's more than 102,4kb

tt
  Reply With Quote
Old 1st March 2009, 08:23 PM   #6
diyAudio Member
 
Join Date: Jun 2008
Yeah it's OK . Don't worry. My description sounds different when you're thinking of it like K is the output with the current set resistor in series with the load. I do a lot of temporary test builds and it's easier for me to put the resistor across the pins directly and bolt the chip to chassis or plate. It all amounts to the same thing

Take a look at this page on Pete Millet's site. There's a diagram showing the hook-up. Just put in your 470 Ohm instead of the 600 Ohm one shown.
  Reply With Quote
Old 2nd March 2009, 08:20 PM   #7
diyAudio Member
 
Join Date: Nov 2007
Location: Dallas
Tap an output at the plate, and its just a triode driving a load.
The constant current provides only bias current for the plate,
and a high CCS impedance does not much otherwise interact
with the either the plate or the load.

-----------

Tap output at CCS-K, now its a source follower of extremely
high Gm. Following the Triode's pure Mu. The Triode's plate
sees a nearly constant current, barely any of the real load.

Could be good or bad, depending wether you don't mind
losing the normal triode interaction between the plate and
the load. As the real load will appear driven only by sand.

-----------

Tap an output halfway up the current sense resistor, and you
have a Triode driving half the load (or twice the apparent load
impedance) as seen in series with the lower half of the current
sense resistance.

The CCS is tricked into driving the other half of the load exactly
in opposition to the Triode, in series with the other half of the
current sense resistance. A near perfect "through the listening
glass" anti-clone of the reference Triode!

Net result: like Twin triodes in Parallel SE. Driving the real load
in series with 1/4 of the total current sense resistance. Most
of the triode flavor and single-endedness is preserved. But you
get some useful boost out of the sand, in addition to constant
bias current.

This recurring concept has been re-invented over and over:
Anti-Triode, Aleph, SEPP, Paraphase. Exactly the same thing!
Only different in name and specifics of implementation.

This is a real viable option to consider with the 10M45S.
  Reply With Quote
Old 3rd March 2009, 02:49 AM   #8
diyAudio Member
 
Join Date: Jun 2008
Thanks kenpeter! You opened a new door and the fresh air is nice !
  Reply With Quote
Old 3rd March 2009, 06:07 PM   #9
diyAudio Member
 
Join Date: Jun 2003
Location: Portugal
Thanks kenpeter i will do my best trying to understand your expertise.
Please, i will be grateful and i don't want to bother you more, but can you looking at the schematic , say to me if it is advisable or not to introduce a 10M45S ,and if yes where ?
Thank you once more.

tt
  Reply With Quote
Old 3rd March 2009, 07:10 PM   #10
diyAudio Member
 
Join Date: Jun 2003
Location: Portugal
This is my unfinished , upgradeable for life amp :


Click the image to open in full size.

[img=http://img3.imageshack.us/img3/9039/pc070085.th.jpg]
  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
10m45s LTspice model dave slagle Tubes / Valves 12 8th February 2014 06:02 AM
LTP CCS IXYS with 10m45s opinions aroS3 Tubes / Valves 7 30th May 2009 02:47 AM
IXYS 10M45S current regulators, qty. 36 zigzagflux Swap Meet 2 10th May 2009 12:58 PM
Wtb; 10m45s Cobra2 Swap Meet 9 26th November 2008 05:17 AM
Sub integration JRKO Subwoofers 28 13th September 2006 09:29 AM


New To Site? Need Help?

All times are GMT. The time now is 08:14 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