Build a VT100? - Page 2

dshortt9 · 9th February 2008, 03:35 PM

Don't forget that you need output taps at 4, 8, and 16 ohms in order to supply the cathode feedback to the output tubes. I'm not sure if that can be accomplished with Lundahl transformers. I'm not saying that they cannot be used this way, just something to check into.

petera77 · 22nd February 2008, 05:00 PM

After reviewing the schematic for a VT100 MKIII, I can see the OPT and other proprietary parts are going to be hard to source.

So now I'm considering a modified Williamson design:

http://home.att.net/~chimeraone/tube...illiamson.html

Any thoughts?

Eli Duttman · 22nd February 2008, 10:02 PM

Quote:

Originally posted by petera77
After reviewing the schematic for a VT100 MKIII, I can see the OPT and other proprietary parts are going to be hard to source.

So now I'm considering a modified Williamson design:

http://home.att.net/~chimeraone/tube...illiamson.html

Any thoughts?

Unless you use absolutely top notch O/P trafos in a Williamson amp, the phase shifts will KILL you.

Phase shifts are MUCH less problematic in a Mullard style circuit.

22nd February 2008, 05:00 PM	#12
petera77 diyAudio Member Join Date: Feb 2008	OK, so that idea is out After reviewing the schematic for a VT100 MKIII, I can see the OPT and other proprietary parts are going to be hard to source. So now I'm considering a modified Williamson design: http://home.att.net/~chimeraone/tube...illiamson.html Any thoughts?

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Audio research vs55/VT50/VT100	jouch	Tubes / Valves	2	7th June 2011 04:58 PM
ARC VT100 driver adjustment	kenneth	Tubes / Valves	6	23rd January 2010 01:38 PM
build my first full ranger,let's build another one:a small fullrange high end pc-spea	then_dude	Full Range	2	30th November 2005 07:54 AM
Do i need to build main supply (240v) filter?Or build power distribution?	thomgun_lc	Chip Amps	9	16th September 2005 09:52 AM
What amp to build?	savenger	Solid State	2	4th November 2004 06:42 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	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

9th February 2008, 03:35 PM	#11
dshortt9 diyAudio Member Join Date: Apr 2001 Location: Milwaukee, Wisconsin	Don't forget that you need output taps at 4, 8, and 16 ohms in order to supply the cathode feedback to the output tubes. I'm not sure if that can be accomplished with Lundahl transformers. I'm not saying that they cannot be used this way, just something to check into.