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

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:	3054
Size:	86.8 KB
ID:	241   Click image for larger version

Name:	IMG_2057.jpg
Views:	1511
Size:	63.8 KB
ID:	242  
alexcp's Avatar
diyAudio Member
Posted in Tube power amps
Views 4023 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:	370
Size:	51.8 KB
ID:	439   Click image for larger version

Name:	IMG_0337.jpg
Views:	191
Size:	46.8 KB
ID:	440   Click image for larger version

Name:	IMG_0335.jpg
Views:	292
Size:	48.3 KB
ID:	441   Click image for larger version

Name:	IMG_0333.jpg
Views:	255
Size:	48.7 KB
ID:	442   Click image for larger version

Name:	IMG_0329.jpg
Views:	315
Size:	52.9 KB
ID:	443  

Click image for larger version

Name:	IMG_0327.jpg
Views:	1828
Size:	66.6 KB
ID:	444  
alexcp's Avatar
diyAudio Member
Posted in Tube power amps
Views 1641 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 2744 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 580 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 666 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 900 Comments 1 DougL is offline
Old

Binding posts/RCA

Posted 27th July 2010 at 04:11 AM by stripe157

Click the image to open in full size.
diyAudio Member
Posted in Uncategorized
Views 624 Comments 2 stripe157 is offline
Old

How low can you go?

Posted 26th July 2010 at 06:46 AM by abraxalito
Updated 31st August 2010 at 04:28 AM by abraxalito

The prices of DVD players just keep on going down here. Yesterday I bought my very first 99RMB [that's under $15] model in Carrefour. I couldn't wait to get home to see how it sounded.

First up I listened to one of my favourite BIS recordings - Mozart 40 in a version for piano, flute and strings. The sound really wasn't as bad as I'd expected - the cello sounded really 'reedy' rather than full-bodied and the flute was akin to a sopranino recorder in its higher register with very little bloom. But there was a fair approximation to a soundstage and really quite decent dynamics, not at all 'bitstream'.

Rebecca Pidgeon's 'Spanish Harlem' is the test disc I use to check for sibilance (it has lots of 's' sounds), and sure enough there was some but definitely not terrible considering the price.

This undoubtedly had potential for the price - I wondered if it could be improved. Inside almost all the functions are integrated on the MediaTek chip (although it...
Attached Thumbnails
Click image for larger version

Name:	P2200409a.JPG
Views:	436
Size:	45.2 KB
ID:	192   Click image for larger version

Name:	P2200410a.JPG
Views:	433
Size:	50.0 KB
ID:	193   Click image for larger version

Name:	P2200413a.JPG
Views:	365
Size:	90.0 KB
ID:	194   Click image for larger version

Name:	P2200416a.JPG
Views:	359
Size:	67.4 KB
ID:	195  
abraxalito's Avatar
diyAudio Member
Posted in Uncategorized
Views 802 Comments 1 abraxalito is offline
Old

Chassis by Dell... with tubes

Posted 20th July 2010 at 06:15 PM by stripe157

Click the image to open in full size.
diyAudio Member
Posted in Uncategorized
Views 378 Comments 0 stripe157 is offline
Old

Chassis by Dell

Posted 20th July 2010 at 05:00 PM by stripe157
Updated 27th July 2010 at 07:48 AM by stripe157

Under construction:
Click the image to open in full size.

Click the image to open in full size.

Front:
Click the image to open in full size.

With some black satin sprayed on:
Click the image to open in full size.

Click the image to open in full size.

With TubeLab.com's Simple SE board:
Click the image to open in full size.

Click the image to open in full size.
diyAudio Member
Posted in Uncategorized
Views 402 Comments 0 stripe157 is offline
Hide this!Advertise here!

New To Site? Need Help?

All times are GMT. The time now is 09:55 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