Poll

Which extra amp would you like to hear Sunday?

Acrosound Ultralinear MK2s
4 (30.8%)
Sun Audio SV2a3
2 (15.4%)
Mandaville Horus 2a3 monoblocs
3 (23.1%)
Maggotbox EL84 SEP amp
1 (7.7%)
Eico HF81
3 (23.1%)

Total Members Voted: 7

Homebrew tube listening session Sun Feb 24 12:30-4:30

0 Members and 1 Guest are viewing this topic. Read 7594 times.

daves

  • Full Member
  • Posts: 978
I have sold off a few things, which prompted me to go in the back room and dig up a couple of long unused pieces of tube gear... Willie will like these.
The amp is an old Conn or Rodgers organ amp with Sansui 1000a output transformers, and a 5881 push-pull configuration, built by Mark Rotsch.

The preamp is a pre WWII line stage with 37 tubes, one of the grandparents of the 6sn7 tube, in gorgeous rosewood cabinets.




The usual setup... we have some drinks. Help out with an appetizer or drinks, bring some tunes.
We will have the low mu preamp setup on the Altecs, the big Threshold setup on the big Thiels, and the First Watt F6 Clone, the Anthem preamp, a phono pre, on some way old 1950s JBLs.
« Last Edit: 18 Feb 2019, 11:09 pm by daves »

justauby

  • Jr. Member
  • Posts: 50
Re: Homemade tube system
« Reply #1 on: 14 Jan 2019, 08:28 pm »
Stop posting beautiful pics of gear! My wallet can't handle this anymore  :lol:

Scott F.

Re: Homemade tube system
« Reply #2 on: 14 Jan 2019, 09:31 pm »
Dave,

How quiet is that line stage? Is that a hum pot I see on the power supply? How is the gain?


I'm curious :scratch:

daves

  • Full Member
  • Posts: 978
Re: Homemade tube system
« Reply #3 on: 14 Jan 2019, 09:51 pm »
Scott, it is pretty quiet. I don’t hear any noise with it cranked all up on the 19s. The digging I did shows about 10 dB gain. The knob on the power supply is the on switch, and from right to left on the pre are the non detented balance, the input selector, and then a pronounced step detent gain attenuator.

Underneath are some luscious filter caps!
« Last Edit: 19 Feb 2019, 04:53 pm by daves »

FullRangeMan

  • Volunteer
  • Posts: 20386
  • To whom more was given more will be required.
    • Never go to a psychiatrist, adopt a straycat or dog. On the street they live only two years average.
Re: Homemade tube system
« Reply #4 on: 14 Jan 2019, 11:18 pm »
This is a great tube device, dont shy to post more photos :thumb:
Those times people used big power transformers, not small ones as today.

Ericus Rex

Re: Homemade tube system
« Reply #5 on: 14 Jan 2019, 11:43 pm »
I count only four, where are the other 33 tubes?



Seriously though, way cool!

sturgus

Re: Homemade tube system
« Reply #6 on: 14 Jan 2019, 11:56 pm »
Sweet looking!!!

daves

  • Full Member
  • Posts: 978
Re: Homemade tube system
« Reply #7 on: 15 Jan 2019, 01:38 am »
The Mundorf Silver M caps are the bomb on this preamp





Scott F.

Re: Homemade tube system
« Reply #8 on: 15 Jan 2019, 03:42 am »
Nice!

daves

  • Full Member
  • Posts: 978
Re: Homebrew tube listening session Sun Feb 24 12:30-4:30
« Reply #9 on: 13 Feb 2019, 09:22 pm »
Bump for the event

Freo-1

Re: Homebrew tube listening session Sun Feb 24 12:30-4:30
« Reply #10 on: 13 Feb 2019, 09:55 pm »
Should be a good time had by all.  Wish I was closer, as I would bring a Thomas Mayer 6AH4 clone preamp to the event.

daves

  • Full Member
  • Posts: 978
Re: Homebrew tube listening session Sun Feb 24 12:30-4:30
« Reply #11 on: 13 Feb 2019, 10:17 pm »
Freo, I would be honored if you came for a visit with your Mayer! Maybe you could pilot a boat up The Mississippi to St. Louis; it would be quite a trip!

daves

  • Full Member
  • Posts: 978
Re: Homebrew tube listening session Sun Feb 24 12:30-4:30
« Reply #12 on: 13 Feb 2019, 10:26 pm »
How about paella for the snack?






daves

  • Full Member
  • Posts: 978
Re: Homebrew tube listening session Sun Feb 24 12:30-4:30
« Reply #13 on: 15 Feb 2019, 07:11 pm »
So far, we have RSVPs from
Bryan
Willie
Kent
Adrian
Jake
Steve
Jack
Bob
Debbie and Mel
Mike
Damon
Gordon
Mary Kay
Jerry
Ken
Bob
Rich
Susan
Don
Bryan
Gene
Bruce?
Kevin
« Last Edit: 24 Feb 2019, 03:09 pm by daves »

daves

  • Full Member
  • Posts: 978
Re: Homebrew tube listening session Sun Feb 24 12:30-4:30
« Reply #14 on: 15 Feb 2019, 11:04 pm »
For the fourth system, we may run one of the following tube amps with a pair of vintage Altecs upstairs.





The 1956 Acrosound Ultralinear Mark II kits.


« Last Edit: 26 Feb 2019, 07:50 pm by daves »

daves

  • Full Member
  • Posts: 978
Re: Homebrew tube listening session Sun Feb 24 12:30-4:30
« Reply #15 on: 15 Feb 2019, 11:06 pm »



The circa 2000 Sun Audio SV2A3 kit wirh 2A3s.
« Last Edit: 26 Feb 2019, 07:51 pm by daves »

daves

  • Full Member
  • Posts: 978
Re: Homebrew tube listening session Sun Feb 24 12:30-4:30
« Reply #16 on: 15 Feb 2019, 11:06 pm »



The JFL Horus served as an inspiration for Eric Mandaville to built these from scratch, also 2A3 based.
« Last Edit: 26 Feb 2019, 07:56 pm by daves »

daves

  • Full Member
  • Posts: 978
Re: Homebrew tube listening session Sun Feb 24 12:30-4:30
« Reply #17 on: 15 Feb 2019, 11:08 pm »



Mike Stehr custom modded this lowly Magnavox console pull, and gloriously retromodded it as a Single ended Stereo 7189 based amp.
« Last Edit: 26 Feb 2019, 07:59 pm by daves »

daves

  • Full Member
  • Posts: 978
Re: Homebrew tube listening session Sun Feb 24 12:30-4:30
« Reply #18 on: 15 Feb 2019, 11:11 pm »



This is a Sean Casper effort from Chicago, it is a Western Electric 91a knockoff, using a WE 421 dual triode as the output tube. Quite tasty!
« Last Edit: 26 Feb 2019, 08:01 pm by daves »

daves

  • Full Member
  • Posts: 978
Re: Homebrew tube listening session Sun Feb 24 12:30-4:30
« Reply #19 on: 15 Feb 2019, 11:14 pm »



In the realm of hitting harder than its weight class, the Eico HF81 is one of the evergreen standard bearers for a great sounding EL84 push pull integrated. This one was rebuilt by Mike Missel.
« Last Edit: 26 Feb 2019, 08:04 pm by daves »