schematic from this amp 45/717a/5u4.. - Page 2 - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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 12th October 2011, 04:08 PM   #11
kevinkr is offline kevinkr  United States
diyAudio Moderator
 
kevinkr's Avatar
 
Join Date: Sep 2004
Location: Boston, Massachusetts
Blog Entries: 6
Quote:
Originally Posted by directdriver View Post
What's wrong with using pentode? Have you listened to it or an amp using pentode driving a triode? Didn't the Western Electric 91 use the same thing? If designed right, I don't see any reason to object to it.

.
Depends a whole lot on the pentode used, some of the more modern high transconductance types are quite good at it, the concern is always going to be the effect of output tube miller capacitance on the HF response.. High transconductance pentodes with modestly sized plate resistors running at high currents should slew well enough at high frequencies and shouldn't have a problem to well beyond 20kHz..
__________________
"Extraordinary claims require extraordinary evidence." - Carl Sagan
  Reply With Quote
Old 28th July 2012, 04:15 PM   #12
maximka is offline maximka  Russian Federation
diyAudio Member
 
Join Date: Oct 2010
Tell those who have wills voltage characteristics 717A
  Reply With Quote
Old 19th August 2013, 08:37 PM   #13
Rewind is offline Rewind  Sweden
diyAudio Member
 
Rewind's Avatar
 
Join Date: Jan 2009
Location: Oslo
Quote:
Originally Posted by ThorstenL View Post
Konnichiwa,

I have decided to post the Schematic in another on-line group with pretty complete detail, so also find it here, in context. It is basically 99%, one or two values may be slightly different, but not much.

If you want to copy the Amplifier you do of course need the iron, considering fit/finish, component quality and inclusion of NOS Valves I'd think it's worth giving Yamamoto the business and buying the Kit if you want to build the Amplifier, a Set of Tamura Transformers and a nice case plus the valves will take most of the cost of the kit.... ;-)

Sayonara
Can't really afford a $2400 amp as a student. What should I look for if I want to find similar irons?
  Reply With Quote
Old 19th August 2013, 08:59 PM   #14
diyAudio Member
 
Palustris's Avatar
 
Join Date: Aug 2006
Location: Cape Cod
Check out Lundahl to see what kind of "budget" transformers they recommend.

Lundahl Transformers
  Reply With Quote
Old 19th August 2013, 09:04 PM   #15
Rewind is offline Rewind  Sweden
diyAudio Member
 
Rewind's Avatar
 
Join Date: Jan 2009
Location: Oslo
Lundahl - budget?

The thing is I am a noob when it comes to transformers. I see units like "CT" and I have no clue what is going on. What values should the transformers in the Yamamoto A-08 have?
  Reply With Quote
Old 8th October 2015, 08:08 AM   #16
diyAudio Member
 
QSerraTico_Tico's Avatar
 
Join Date: Oct 2004
Schematic:
http://www.jacmusic.com/Yamamoto/ima...A08-Manual.jpg

Last edited by QSerraTico_Tico; 8th October 2015 at 08:10 AM.
  Reply With Quote
Old 8th October 2015, 08:21 AM   #17
diyAudio Member
 
QSerraTico_Tico's Avatar
 
Join Date: Oct 2004
Quote:
Originally Posted by codyzox View Post
I need it also...Can someone post details with original shematic and parts list (also from which manufacturer are parts exactly). It would be a great help, not just for me i think...Big thanks in advance...
Lot of info here:
★ J A C - M U S I C ★ EMISSION LABS TUBES ★ YAMAMOTO SOUNDCRAFT ★ NOS TUBES ★ You must like:
http://www.jacmusic.com/Yamamoto/htm...it-version.htm
  Reply With Quote
Old 9th November 2015, 03:06 AM   #18
diyAudio Member
 
Join Date: Mar 2013
Quick question here: what is the original Tamura output transformer model used in Yamamoto A-08/s? And is there any replacement from Lundahl amorphous core lineup? Thanks.
  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
Matched pairs 717A Western Electric/Tung Sol phrarod Vendor's Bazaar 2 12th April 2016 10:20 PM
NAD 304 Schematic Makofoed-6sn7 Solid State 5 3rd May 2006 06:41 AM
717a plate volts 845amp Tubes / Valves 6 30th December 2005 11:22 PM
717a Datasheet mrstone Tubes / Valves 7 5th August 2004 05:05 PM
What do you think about this schematic? PanzerLord Solid State 9 8th March 2004 06:43 PM


New To Site? Need Help?

All times are GMT. The time now is 04:56 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.
Copyright 1999-2016 diyAudio

Content Relevant URLs by vBSEO 3.3.2
Wiki