My brew of the "Darling" - 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 1st August 2007, 11:50 PM   #1
arnoldc is offline arnoldc  Philippines
diyAudio Member
 
Join Date: Apr 2003
Location: Makati
Send a message via Yahoo to arnoldc
Default My brew of the "Darling"

I made my first ever online order for a tube project some 4 years ago. That order is for a JE Labs 2A3 which was sent to Angela.com which also contained a pair of 8532 and 1626 - parts for the Darling amp.

I haven't put those tubes to use since the order arrived.

Yesterday, while I was waiting for my students to finish ther labs, I started scribbling something, which ended up like this-

(photo was taken after I completed the amp)
Attached Images
File Type: jpg dsc02509.jpg (43.1 KB, 1595 views)
  Reply With Quote
Old 2nd August 2007, 12:03 AM   #2
arnoldc is offline arnoldc  Philippines
diyAudio Member
 
Join Date: Apr 2003
Location: Makati
Send a message via Yahoo to arnoldc
My chassis has only one hole sized for for a 9-pin tube, so I cannot use my 8532 on this circuit, as they're 7-pin and single triode. My bias towards the 407A sonics on my preamp led me to use a close "cousin" - the 2C51 (while I also have the Western Electric 396A, it will be put to service later) which is a 9-pin dual triode with 6.3V filaments (unlike the 20/40V of the 407A).

I got good results using the diyAudio CCS in my other project, so why not use it again. While my "RS Components design tool" shows the CCS set at 8mA, the actual circuit had 10mA because I don't have a 125R resistor. Tonight, I will put in a Bourns multi-turn variable resistor so I can dial it in at 8mA.

SY was a big influence on my choice with regards to biasing, so the 2C51 was biased using Yellow LEDs which should give me 2V or so.

I decided not to re-invent the wheel and went ahead with the original bias scheme of the 1626- a shared 500R, bypassed by a capacitor.

I have some left-over power transformer and output transformers (5K:8/16R) from a previous 807 project which I re-used for this amp.

Just before midnight I was able to complete assembly, did some voltage measurements which came very close to my scribble. With that, I hooked it up to my speakers and played some music.
Attached Images
File Type: jpg dsc02508.jpg (77.2 KB, 1342 views)
  Reply With Quote
Old 2nd August 2007, 12:14 AM   #3
arnoldc is offline arnoldc  Philippines
diyAudio Member
 
Join Date: Apr 2003
Location: Makati
Send a message via Yahoo to arnoldc
Like most of my projects, there are no exotic parts, even though I'm tempted to use my Riken resistors and MultiCap RTX coupling caps.

You'll see on the photo that my 1626 cathode capacitor is a white-coffin bypassed with a generic 220uF electrolytic. The coupling caps are Auricaps, and the power supply is a simple CRCRC with generic electrolytics and white coffin as well.

By the way, there's 1K grid stopper to the grid of the 1626 (not in schematic) because my 220K grid leak resistors have too short leads

So how does it sound? It has a different character which I tend to like, sweet and mellow, for a change. I can't play really loud as my neighbors might complain but the vocals reproduction is glorious. It does not have the punch and kick of my 2A3 or 45, but it does bass deep enough to give me some satisfaction.
Attached Images
File Type: jpg dsc02504.jpg (95.9 KB, 1312 views)
  Reply With Quote
Old 2nd August 2007, 01:38 AM   #4
diyAudio Member
 
Sal Brisindi's Avatar
 
Join Date: Nov 2006
Great job on the amp, nice, simple yet elegant. I have parts to build a Darling so one of these days, month or years I will get to it... :-)

Regards,
Sal Brisindi
  Reply With Quote
Old 2nd August 2007, 05:16 AM   #5
alexg is offline alexg  Philippines
diyAudio Member
 
alexg's Avatar
 
Join Date: Jan 2005
Location: Philippines
That amp looks great!

Is the 2C51 similar to 5670? How much voltage swing you need to drive the 1626?

I would like to make one like your Darling!

Arnold, question: which in your opinion would sound better a 1626 or a 12b4 flea powered amp? Thanks.
  Reply With Quote
Old 2nd August 2007, 06:41 AM   #6
arnoldc is offline arnoldc  Philippines
diyAudio Member
 
Join Date: Apr 2003
Location: Makati
Send a message via Yahoo to arnoldc
Hi Sal, yes, it took me four years to do this

Hi Alex, you're right about 5670. I just need some 60Vp-p to drive the 1626.

On the 1626 vs. 12B4, I can't comment because have not made a 12B4 amp yet, but you're tempting me. However, the 1626 with its ST-bottle is physically very attractive for me
  Reply With Quote
Old 2nd August 2007, 07:12 AM   #7
alexg is offline alexg  Philippines
diyAudio Member
 
alexg's Avatar
 
Join Date: Jan 2005
Location: Philippines
Quote:
Originally posted by alexg
That amp looks great!

Is the 2C51 similar to 5670? How much voltage swing you need to drive the 1626?

I would like to make one like your Darling!

Arnold, question: which in your opinion would sound better a 1626 or a 12b4 flea powered amp? Thanks.
I know you like the 12b4 and I thought about you yesterday while looking at a 12b4 amp circuit, producing almost same power as the 1626.
  Reply With Quote
Old 2nd August 2007, 07:21 AM   #8
arnoldc is offline arnoldc  Philippines
diyAudio Member
 
Join Date: Apr 2003
Location: Makati
Send a message via Yahoo to arnoldc
Which one is that? The one driven by a 6AU6?
  Reply With Quote
Old 2nd August 2007, 07:46 AM   #9
alexg is offline alexg  Philippines
diyAudio Member
 
alexg's Avatar
 
Join Date: Jan 2005
Location: Philippines
Quote:
Originally posted by arnoldc
Which one is that? The one driven by a 6AU6?
I have not seen the one with the 6au6 driver, the one I was looking at is driven by half a 12ax7. It said to produce 0.9watt.

Am really tempted to do this 12b4 amp.


  Reply With Quote
Old 2nd August 2007, 08:32 AM   #10
arnoldc is offline arnoldc  Philippines
diyAudio Member
 
Join Date: Apr 2003
Location: Makati
Send a message via Yahoo to arnoldc
Ah, you're talking about the Abraxas audio I believe. Did he designed it for full range use?
  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
What makes an amplifier "bright", "warm", or "neutral"? JohnS Solid State 51 13th December 2009 06:42 PM
Charcoal "Supreem" hi-density foam "enclosure" IG81 Multi-Way 0 23rd April 2009 01:34 PM
Need help with PS for 1626 "Darling" amp needtubes Tubes / Valves 7 6th March 2005 03:46 PM
Some final pics of "Stacks" revisited and "Askew" with stand Andy G Multi-Way 2 3rd February 2005 06:07 AM
Anyone used Scan-Speak's "Flow Resistors" or "Aperiodic Vents"? Ignite Multi-Way 3 18th November 2001 08:42 AM


New To Site? Need Help?

All times are GMT. The time now is 11:15 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