diyAudio - Blog Entries
Go Back   Home > Forums > Blogs

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
Old

Elekit TU-879S

Posted 12th August 2010 at 07:24 PM by alexcp (My DIY projects)
Updated 16th March 2013 at 02:02 PM by alexcp

Elekit TU-879S is the best sounding kit I have ever built. Thank you TubeDepot.com for selling these kits. With my DIY full range speakers I mentioned a couple of posts earlier, the sound is fantastic.

Update: one of the original 6L6 tubes got blue sparks inside. As this amp can use KT88, KT66, or EL34 without any adjustment or modification, I replaced both 6L6s with EL34s left from the K4040 project, but the sound deteriorated. A replacement 6L6 from TubeDepot.com restored everything.
Attached Thumbnails
Click image for larger version

Name:	IMG_2071.jpg
Views:	1224
Size:	35.6 KB
ID:	243  
alexcp's Avatar
diyAudio Member
Posted in Tube power amps
Views 2329 Comments 2 alexcp is offline
Old

First Watt B1 clone

Posted 12th August 2010 at 07:19 PM by alexcp (My DIY projects)
Updated 12th May 2013 at 04:09 PM by alexcp (Added photos)

What to say... B1 is a great design by Nelson Pass. Easy to build, absolutely transparent to the sound, compact, PCBs are available. I built one, using Nelson Pass' gerbers for making my own PCB, in an enclosure from diyenclosures.com (which sadly seems to be defunct now). The big blue film caps are 10uF Evox Rifa PHE426.

Update: I added a relay input selector, which reduced crosstalk between inputs. I also built another B1 clone (the last three photos), in an enclosure 1U (40mm) high.
Attached Thumbnails
Click image for larger version

Name:	diyaudio11.jpg
Views:	325
Size:	159.1 KB
ID:	1035   Click image for larger version

Name:	diyaudio01.jpg
Views:	530
Size:	192.6 KB
ID:	1036   Click image for larger version

Name:	diyaudio02.jpg
Views:	754
Size:	188.8 KB
ID:	1037   Click image for larger version

Name:	diyaudio04.jpg
Views:	181
Size:	129.8 KB
ID:	1038   Click image for larger version

Name:	diyaudio06.jpg
Views:	182
Size:	155.7 KB
ID:	1039  

Click image for larger version

Name:	diyaudio07.jpg
Views:	297
Size:	136.9 KB
ID:	1040   Click image for larger version

Name:	diyaudio10.jpg
Views:	146
Size:	144.5 KB
ID:	1041   Click image for larger version

Name:	diyaudio77.jpg
Views:	717
Size:	195.9 KB
ID:	1042   Click image for larger version

Name:	diyaudio68.jpg
Views:	254
Size:	132.6 KB
ID:	1043   Click image for larger version

Name:	diyaudio70.jpg
Views:	181
Size:	144.5 KB
ID:	1044  

alexcp's Avatar
diyAudio Member
Posted in Preamps
Views 2842 Comments 0 alexcp is offline
Old

Zen V4

Posted 12th August 2010 at 05:16 PM by alexcp (My DIY projects)
Updated 14th May 2013 at 12:46 PM by alexcp (Amp reworked)

Nelson Pass' Penultimate Zen (aka Zen V4) proved trickier to build than the simple schematic suggested. I used a chassis from designbuildlisten and PCBs made with the gerbers posted on passdiy.com. Initially I used some Chinese electrolytic capacitors that were easily available, but the sound was not good at all. I replaced them with ELNA for Audio, and things improved greatly. I found that the apparent simplicity of the schematic belies the difficulty of making it right.
Update: I replaced the gain stage MOSFET with a SemiSouth SiC JFET and got a noticeable improvent in both the sound and the measured performance, see a separate post.
Attached Thumbnails
Click image for larger version

Name:	ZV4-1.jpg
Views:	125
Size:	152.5 KB
ID:	1062   Click image for larger version

Name:	ZV4-2.jpg
Views:	237
Size:	227.7 KB
ID:	1063   Click image for larger version

Name:	ZV4-3.jpg
Views:	136
Size:	213.4 KB
ID:	1064   Click image for larger version

Name:	ZV4-4.jpg
Views:	92
Size:	168.5 KB
ID:	1065   Click image for larger version

Name:	ZV4-5.jpg
Views:	357
Size:	202.8 KB
ID:	1066  

Click image for larger version

Name:	ZV4-6.jpg
Views:	273
Size:	216.5 KB
ID:	1067   Click image for larger version

Name:	ZV4-7.jpg
Views:	196
Size:	175.4 KB
ID:	1068   Click image for larger version

Name:	ZV4-8.jpg
Views:	117
Size:	193.7 KB
ID:	1069   Click image for larger version

Name:	ZV4-9.jpg
Views:	173
Size:	182.2 KB
ID:	1070  
alexcp's Avatar
diyAudio Member
Views 2953 Comments 0 alexcp is offline
Old

Fostex BK-20

Posted 12th August 2010 at 05:06 PM by alexcp (My DIY projects)
Updated 15th August 2010 at 04:18 PM by alexcp

Having built a few amplifiers, I wanted to build a pair of speakers and settled on Fostex BK-20 kits from Madisound with Fostex FE-206E 8" full range drivers. I've always considered carpentry not my cup of tea, so gluing, sanding, and painting the speakers took longer than expected. However, I am very satisfied with the sound.
alexcp's Avatar
diyAudio Member
Posted in Speakers
Views 2814 Comments 4 alexcp is offline
Old

Velleman K4040

Posted 12th August 2010 at 04:53 PM by alexcp (My DIY projects)
Updated 26th May 2011 at 12:54 PM by alexcp

Then was the K4040 from Velleman. Contrary to some reviews, I found this amp sounding rather nice, particularly after I replaced the EL34 tubes in the output stage with separately purchased matched quads. However, the sound does not quite match the price, and I keep this amp mostly for its looks.

Update: I modified this amplifier, leaving little of the original design. See a later post with the details.
Attached Thumbnails
Click image for larger version

Name:	IMG_2056.jpg
Views:	3521
Size:	86.8 KB
ID:	241   Click image for larger version

Name:	IMG_2057.jpg
Views:	1776
Size:	63.8 KB
ID:	242  
alexcp's Avatar
diyAudio Member
Posted in Tube power amps
Views 4353 Comments 0 alexcp is offline
Old

S5 Electronics "L" series tube amps

Posted 12th August 2010 at 04:52 PM by alexcp (My DIY projects)
Updated 16th March 2013 at 01:55 PM by alexcp

I started with a Model 8LS stereo amp from S5 electronics. Very easy to build, nice with vocals, but not quite HiFi. Later I put it into a Hammond enclosure and replaced the tranformers with Edcors. Also, built a Model 16LS, which is the same thing with a doubled output stage, giving a very similar sound. Both use a 5670 double triode in the voltage amplifier and phase splitter, and 2x6005 (4x for the 16LS) in the PP output stage.
Attached Thumbnails
Click image for larger version

Name:	IMG_0339.jpg
Views:	457
Size:	51.8 KB
ID:	439   Click image for larger version

Name:	IMG_0337.jpg
Views:	223
Size:	46.8 KB
ID:	440   Click image for larger version

Name:	IMG_0335.jpg
Views:	410
Size:	48.3 KB
ID:	441   Click image for larger version

Name:	IMG_0333.jpg
Views:	321
Size:	48.7 KB
ID:	442   Click image for larger version

Name:	IMG_0329.jpg
Views:	376
Size:	52.9 KB
ID:	443  

Click image for larger version

Name:	IMG_0327.jpg
Views:	2241
Size:	66.6 KB
ID:	444  
alexcp's Avatar
diyAudio Member
Posted in Tube power amps
Views 1777 Comments 0 alexcp is offline
Old

Aleph "MJ" using SemiSouth SJEP120R100 outputs

Posted 8th August 2010 at 09:29 PM by Tea-Bag
Updated 9th August 2010 at 12:34 PM by Tea-Bag

So I believe I am finished with the Mini-A version modified for SemiSouth R100 output. The MJ is not in reference to Michael Jackson, rest his soul. Simply a reference to Mosfet input, JFET output.

Technical pieces:
R8 is a 1K pot. This allow for some DC offset adjustment.
R18, This affects drain current to differential pair. This value is lowered. I chose 220R resistor since I have a bunch of them. Papa presented this as needed on mod's in general for the lower VGS of the R100 (~1.5v)
R19, gate resistor to Power JFET R100. This is lowered to 47R. We see with F1J and F2J that gate resistors are lower.


Rail Voltage is +/-24v
Source voltage is .425v and is largely determined by the 100K pot settings and heatsinks on hand. The real value of the pot is ~ 70-80k here. I let the IRF240's run no higher than 65c and R100's no higher than 70c.


Sound

Previously I had R18 at 392 default and R19...
Tea-Bag's Avatar
diyAudio Member
Posted in Uncategorized
Views 3037 Comments 0 Tea-Bag is offline
Old

Mis-understood ArT - Part II

Posted 6th August 2010 at 10:15 PM by tomtt
Updated 19th January 2011 at 11:42 PM by tomtt

i actually spoke to Taylor Swifts agent.

he cleared up a few unanswered questions,

i had about the 'Kanye/Taylor incident.'

http://img836.imageshack.us/img836/7...itowebcam5.jpg

Click the image to open in full size.

http://gifsoup.com/MTMyODAxNw


http://www.radioworld.com/article/105742

http://www.fundinguniverse.com/company-histories/Ballantyne-of-Omaha-Inc-Company-History.html
tomtt's Avatar
diyAudio Member
Posted in Uncategorized
Views 637 Comments 0 tomtt is offline
Old

Up and running

Posted 4th August 2010 at 09:08 PM by stripe157

As of August 4, at 4:01, this is an official, working amplifier!

Once I decide on a volume control knob, I'll make a wooden face plate for it and call it finished... for now.
diyAudio Member
Posted in Uncategorized
Views 720 Comments 1 stripe157 is offline
Old

PassDIY LDR

Posted 30th July 2010 at 10:10 PM by DougL
Updated 14th September 2010 at 06:33 PM by DougL

http://www.diyaudio.com/forums/analo...ml#post2258073

This looks cool.
diyAudio Member
Views 945 Comments 1 DougL is offline
Hide this!Advertise here!

New To Site? Need Help?

All times are GMT. The time now is 11:31 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