Home » Audio » Thermionic Emissions » Me Want Valve Amp. 8^)
Re: Me Want Valve Amp. 8^) [message #9012 is a reply to message #8997] Wed, 01 June 2005 18:20 Go to previous messageGo to next message
Dave Williams is currently offline  Dave Williams
Messages: 9
Registered: May 2009
Esquire
Hi Russell,

Thanks for the tip. That Mag1515 looks like another good option to consider. Seems hard to find any opinions from anyone who's heard it, though (other than the ones he has posted on his site).

Re: Me Want Valve Amp. 8^) [message #9013 is a reply to message #8999] Wed, 01 June 2005 18:25 Go to previous messageGo to next message
Dave Williams is currently offline  Dave Williams
Messages: 9
Registered: May 2009
Esquire

I know next to nothing about circuit topologies so can't really comment, but I did find myself, in reading his description of the circuit, thinking that it was a freaking miracle that it worked. Wasn't clear to me what ensures that the two phases are balanced other than fortuitous choice of some resistances.

Is there something in particular about paraphase that makes you nervous about it?

Re: Reluctant Virgins [message #9014 is a reply to message #9004] Wed, 01 June 2005 18:27 Go to previous messageGo to next message
Dave Williams is currently offline  Dave Williams
Messages: 9
Registered: May 2009
Esquire
LOL! Now THAT'S comedy.

Thanks for the laugh.

you have plenty ov budget... [message #9020 is a reply to message #8989] Fri, 03 June 2005 16:21 Go to previous messageGo to next message
PakProtector is currently offline  PakProtector
Messages: 935
Registered: May 2009
Illuminati (2nd Degree)
I would recommend a blueprinting/restoration project. It can move into a modification and then with the same parts on to your own design.

It would need good quality parts, and be versatile. There are a fair bit of choices. I'll mention some of the ones which stick out for me.

A Citation II would stretch your budget a bit, a pair of Heathkit W5's would land you closer to the top by the time you have restored them. A pair of Dynaco Mk.IV would allow a bit of budget to try other things when the modification starts to happen. Eico HF 50's are going to land yo near the top of your budget limit, but have good Iron and thus potential...
regards,
Douglas


Seth [message #9021 is a reply to message #8993] Fri, 03 June 2005 16:33 Go to previous messageGo to next message
PakProtector is currently offline  PakProtector
Messages: 935
Registered: May 2009
Illuminati (2nd Degree)
There are a few things to consider when looking at the Kit selection of Iron for that amp.

1. single filament winding for the 2A3's. Not good if well centered cathodes/filaments are not available( and they are *NOT* )

2. The phase splitting is done with an autoformer. I have not liked the sound of this sort of thing in the amps I have experimented on. A grid choke, functioning like a grid choke with balanced drive has worked *MUCH* better. I had a finger in the design of the MQ device, and abandoned the project. It is good on paper and the bench, but I found its sonics lacking.

3. I think the S-230-Q is a better choice of output TX for class A PP 2A3's. 6k6 instead of 5k for the S-240. The 230 is not available from MQ though...neither is the 20-20 Plus series in this a-a load.

4. B+ is a bit on the high side for that load if Class A bias is desired. It also seems to sound better if the operating point is a bit more conservative. Certainly the finals last longer.

There is the group build forum here, if you wish to take on a project with group support.
regards,
Douglas

Hey! [message #9022 is a reply to message #8997] Sat, 04 June 2005 07:27 Go to previous message
PakProtector is currently offline  PakProtector
Messages: 935
Registered: May 2009
Illuminati (2nd Degree)
He's sort of famous! I met him at Jonathan's '04 Tasting. He brought( among other stuff ), a nice PP EL84 amp. He's one of the folks I'd recommend w/o hesitation. I did suggest that he wasn't charging enough for his gear.

I think I'll see if I can't get him to upgrade his line to a big PP 300B kit, or perhaps an E-Linear EL34/6550. Good to see a means of contacting him!
regards,
Douglas


Previous Topic: November 2005 Vacuum Tube Valley Southern California Audio Festival
Next Topic: Power Supply suggestions
Goto Forum:
  


Current Time: Sun Dec 22 00:51:04 CST 2024

Sponsoring Organizations

DIY Audio Projects
DIY Audio Projects
OddWatt Audio
OddWatt Audio
Pi Speakers
Pi Speakers
Prosound Shootout
Prosound Shootout
Miller Audio
Miller Audio
Tubes For Amps
TubesForAmps.com

Lone Star Audiofest