Pentode sounds great - 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 29th August 2008, 03:16 PM   #1
Cassiel is offline Cassiel  Libya
diyAudio Member
 
Cassiel's Avatar
 
Join Date: Sep 2004
Location: Madrid
Default Pentode sounds great

Hi, i have built a little amp with the ecl86.

My surprise is that it sounded better in pentode mode. Triode had a good tone (doesn't always) but the sound was a little opaque and too much laid off for my taste.
Try this with any pentode, el84 anyone?
Only requirement is no bypass caps,input and output stage, and a higher than normal primary impedance - 10.000 Ohms or maybe more if you can.

Lovely sound, clear and natural.
  Reply With Quote
Old 29th August 2008, 04:35 PM   #2
Jeb-D. is offline Jeb-D.  United States
diyAudio Member
 
Jeb-D.'s Avatar
 
Join Date: Nov 2005
Location: SoCal
Quote:
Try this with any pentode, el84 anyone?
George (tubelab) did. He seemed happy with the result.

I've had good luck with other Pentodes as well.
  Reply With Quote
Old 29th August 2008, 04:38 PM   #3
diyAudio Member
 
Boris_The_Blade's Avatar
 
Join Date: Mar 2007
Sometimes those extra two connections scare people, but there's nothing wrong with pentodes!
  Reply With Quote
Old 29th August 2008, 08:51 PM   #4
diyAudio Moderator Emeritus
 
ray_moth's Avatar
 
Join Date: Jan 2004
Location: Jakarta
Stalker, did you use negative feedback (other than unbypassed cathode resistors)? It's common to use it to improve pentode harmonics and damping factor.
  Reply With Quote
Old 30th August 2008, 01:14 PM   #5
Cassiel is offline Cassiel  Libya
diyAudio Member
 
Cassiel's Avatar
 
Join Date: Sep 2004
Location: Madrid
No Ray, only current feedback...but when i get used to the sound i'll try
a voltage feedback loop too. Thought i suspect i'll get an even cleaner sound but with less air and openness.
  Reply With Quote
Old 30th August 2008, 10:16 PM   #6
diyAudio Member
 
aletheian's Avatar
 
Join Date: Apr 2004
Location: Philly
You are not alone, I tend to like the sound of pentodes too--more bite and a more aggressive response typically-- but since I listen to heavier music it makes sense for me. They just seem so unpopular that I have never bothered posting about it.
__________________
Heghlu'meH QaQ jajvam!
  Reply With Quote
Old 30th August 2008, 11:21 PM   #7
diyAudio Moderator Emeritus
 
ray_moth's Avatar
 
Join Date: Jan 2004
Location: Jakarta
Well, aletheian, I'll join you as a pentode fan.

My attraction to pentodes started over 40 years ago and hasn't abated yet. Expressions like pentode authority and pentode slam get the old pulses racing. Of course, I know that triode sound is 'purer', but where's the fun in that?
  Reply With Quote
Old 31st August 2008, 03:05 AM   #8
JandG is offline JandG  United States
diyAudio Member
 
Join Date: Jan 2005
Location: Washington State
I too am getting a high respect for Pentodes in SE as that is all the OT;s I have are SE, but in the last month or so I have ripped though many, many Pentodes & many sound excellent in the normal mode. Now I am off to learn NFB ways, I see there is many, many differnat ways to do it.I tried sceen dive this mourning on a 807 & couldn't get it to work, another day for that G2 drive thing. I like building sperate PS's & Pentodes in that mode give me a good reason to do g2 supplies & experiments. my top dog amp is a DIY PP 6l6 jobber from a very talented fella that used a Fisher 200 OT & adjustable NFB, it is a stunning sounding amp. Yep I like em..
  Reply With Quote
Old 31st August 2008, 06:27 AM   #9
diyAudio Member
 
azazello's Avatar
 
Join Date: Aug 2008
Location: Bulgaria
Quote:
Originally posted by ray_moth
Well, aletheian, I'll join you as a pentode fan.

My attraction to pentodes started over 40 years ago and hasn't abated yet. Expressions like pentode authority and pentode slam get the old pulses racing. Of course, I know that triode sound is 'purer', but where's the fun in that?



What is better ? Pure, real sound .....or fun ?
/6C41C - 1/2 of 6C33C -.... sounds like pentod...compromise?/.
__________________
Projects: OTL-OCL 6AS7 Gen. Electric, SEs 2A3 RCA, 300B JJ, 6S4S, 4P1L, EL11 Telefunken, 6AS7 RCA, 6S33S, 6S41S, 6S19P, E84L Siemens, E236L Telefunken, headphone ampl. OTL Loftin White 6AS7 RCA,... PPs 6005 Gen. Electric, EL34 Mullard, 6L6....
  Reply With Quote
Old 31st August 2008, 07:29 AM   #10
diyAudio Moderator Emeritus
 
ray_moth's Avatar
 
Join Date: Jan 2004
Location: Jakarta
Quote:
What is better ? Pure, real sound .....or fun ?
I'm going to respond with the dreaded words "it depends", in this case on your reason for being in this hobby of ours. Good triode sound is well within reach for most people, whereas good pentode sound is more of a challenge (but also more rewarding when you get it right).

Maybe the best approach is to build a nice triode amp and keep it for listening, then build a pentode amp to use for experimenting.
  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
Radio Sounds Great, CDs Sound Terrible sdclc126 Car Audio 5 3rd August 2007 01:22 PM
FS Gainclone Great Chassis, Potted toroidal, great sound PHilgeman Swap Meet 4 2nd May 2006 01:20 PM
A small no-fuss pentode/pentode SE amp Tubes4e4 Tubes / Valves 13 1st January 2006 05:16 AM
sounds great, thanks to everyone that helped. Richie V6 Chip Amps 6 1st January 2005 03:06 PM


New To Site? Need Help?

All times are GMT. The time now is 04:26 AM.


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