Tube audio-phoolery -- more teats on bulls - 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 10th February 2012, 11:55 PM   #1
diyAudio Member
 
jackinnj's Avatar
 
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
Default Tube audio-phoolery -- more teats on bulls

Sterophile reviews the Z-Infinity "Z40" -- and there's a pair of 12AU7's with the only connection to the heaters.
  Reply With Quote
Old 11th February 2012, 12:08 AM   #2
kevinkr is offline kevinkr  United States
diyAudio Moderator
 
kevinkr's Avatar
 
Join Date: Sep 2004
Location: Boston, Massachusetts
Blog Entries: 6
I'm still waiting for my copy of Stereophile to arrive.. I'm a little surprised that they would review something like this..
__________________
"Extraordinary claims require extraordinary evidence." - Carl Sagan
  Reply With Quote
Old 11th February 2012, 12:17 AM   #3
diyAudio Member
 
aardvarkash10's Avatar
 
Join Date: Mar 2007
Location: Auckland, NZ
they are produced at one a minute apparently
__________________
"Folks, you can't prove truthiness with information. You prove truthiness with more truthiness. In a process known as truthinessiness." - Stephen Colbert, The Colbert Report
  Reply With Quote
Old 11th February 2012, 12:26 AM   #4
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
Does it work by ethereal radiation from the tubes? This is an exciting new world of physics.
__________________
You might be screaming "No, no, no" and all they hear is "Who wants cake?" Let me tell you something: They all do. They all want cake.- Wilford Brimley
  Reply With Quote
Old 11th February 2012, 12:45 AM   #5
diyAudio Member
 
smoking-amp's Avatar
 
Join Date: Dec 2001
Location: Hickory, NC
I seem to recall someone posting here once about how they improved the sound after they connected a wire from their amp to just one tube pin. With the heaters lit up here, they must have at least two pins connected in the Z40.
__________________
I want a Huvr-Board!!
  Reply With Quote
Old 11th February 2012, 01:23 AM   #6
diyAudio Member
 
jackinnj's Avatar
 
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
Quote:
Originally Posted by kevinkr View Post
.. I'm a little surprised that they would review something like this..
Atkinson is the "honest broker" -- like Diogenes carrying a lamp in the daylight, but more subtley if you read the measurements portion of the reviews.
  Reply With Quote
Old 11th February 2012, 02:16 AM   #7
diyAudio Member
 
Join Date: Dec 2011
They might as well add a couple of 6BK4Bs or 3A3's with the numbers rubbed off while they're at it. I guess they don't glow enough or look like audio tubes. Get rid of some odd 5 Volt tubes?

Last edited by riccoryder; 11th February 2012 at 02:22 AM.
  Reply With Quote
Old 11th February 2012, 01:40 PM   #8
kevinkr is offline kevinkr  United States
diyAudio Moderator
 
kevinkr's Avatar
 
Join Date: Sep 2004
Location: Boston, Massachusetts
Blog Entries: 6
Actually I read the article this morning and I guess this is the so called grape vine effect. The assertions made in this thread are at best inaccurate. The amplifier has 4 EL34, two 12AU7 and two 12AX7. Except for the filaments the 12AX7 are not connected, Art Dudley comments pretty forthrightly about this and dug far enough to determine that the reason is that the manufacturer uses a standard chassis and had two holes to fill. (Why the manufacturer did not cap the unused holes is a mystery IMHO.)

Jack didn't quite get the story straight.. This is a tube amplifier and has an all tube signal path. Looks quite nice too.
__________________
"Extraordinary claims require extraordinary evidence." - Carl Sagan
  Reply With Quote
Old 11th February 2012, 01:45 PM   #9
diyAudio Member
 
dirkwright's Avatar
 
Join Date: May 2011
Location: Virginia
Quote:
Originally Posted by jackinnj View Post
Atkinson is the "honest broker" -- like Diogenes carrying a lamp in the daylight, but more subtley if you read the measurements portion of the reviews.
I'm surprised that he can hear anything above 5kHz. How old is he now?
  Reply With Quote
Old 11th February 2012, 01:50 PM   #10
diyAudio Member
 
doozerdave's Avatar
 
Join Date: Feb 2012
Location: Kitchener, Ontario
I can see them leaving the tubes with anode and cathode resistors to draw a quiescent current so they don't have to change their HT dropping resistors for mass production, but I can't image that two tubes (with sockets!) and four resistors would be cheaper than stocking a slightly larger value dropping resistor... who knows. Maybe blank plugs are expensive.
  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
From old Philips tube books , just for tube audio DIY friends ! banat Tubes / Valves 25 1st January 2012 12:19 PM
Can the 7AK7 computer tube work as audio output tube ? aldovan Tubes / Valves 10 24th August 2011 06:22 PM
OT for audio but still tube Andrewbee Tubes / Valves 1 12th August 2008 04:29 PM
Cool tube I came across... could it be used for audio? Mach_Y Tubes / Valves 52 12th January 2008 01:13 AM
A new audio tube HollowState Tubes / Valves 50 23rd December 2006 05:41 PM


New To Site? Need Help?

All times are GMT. The time now is 11:33 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