a Dual LA2A - the [silent:arts] version

[do0g]

A stereo set for me as well thanks, shipped to the UK.

Thanks!

 

[Gwaggin390]

i'd take another pcb if you have one

 

[RedNoise]

Hi there...Is there a build thread somewhere???I just received my snow pcbs. :thumb:
Volker : what brand of 10µF/630V & 100nF (made in france) did you use please??
Custom power tran from Rondo right?
Thanks...

 

[[silent:arts]]

[quote author="RedNoise"]Hi there...Is there a build thread somewhere???I just received my snow pcbs. :thumb:
Volker : what brand of 10µF/630V & 100nF (made in france) did you use please??
Custom power tran from Rondo right?
Thanks...[/quote]
build thread in franks forum: http://www.nrgrecording.de/nrg/viewtopic.php?t=405
(would be redundant to do another one here)
the "made in France" cap is a Solen Fast (a canadian brand AFAIK)

 

[RedNoise]

Thx Volker!
Got to register @ NRG. :green:

 

[Kingston]

[quote author="[silent:arts]"]I have had problems with gain over "7" (may be this grid stopper thing), but I changed the gain pot to a 22K log in series with a 75K resistor to get an easier to adjust gain range (still 26dB gain - enough for a compressor / limiter). [/quote]

Could you provide more info about this? Is this related to your PCB version, or a more general LA2A problem?

Have you or anyone looked at it in detail and was it ever completely solved?

 

[[silent:arts]]

I would say it is more a general LA2A issue. the D-LA2A rev02 PCBs have places for gridstopper resistors, shouldn't be a problem with them.

 

[[silent:arts]]

Gentlemen, may I present you the [silent:arts] D-LA2A

I can't believe this was 10 years ago 

 

[mattmartin831]

This is absolutely incredible, definitely adding this to my to-do list.

 

[MiamiBoy]

I'd like to build my own Dual LA2A with this front panel:
Can somebody please help me where to start?
Thanks a lot.

 

[rock soderstrom]

The Dual LA2A build thread is a good place to start. 96 pages of information are waiting for you. There is no step-by-step quide. Just start reading, it is all there. nobody else will do it for you. Have fun!
https://groupdiy.com/index.php?topic=32677.0

 

[[silent:arts]]

There is no step-by-step quide.

Yes. And no kits. This is an old school project.
From the times when you have been lucky to only have a schematic and a working PCB.

 

[dmp]

I'd like to build my own Dual LA2A with this front panel:
Can somebody please help me where to start?
Thanks a lot.

I built one in a 2U case like that and you need to make sure the tubes are not too high so the lid doesn't hit them. Keep it in mind as you source parts (tube sockets, standoffs)
I think there is some info in the thread about it.

 

[MiamiBoy]

Yes. And no kits. This is an old school project.
From the times when you have been lucky to only have a schematic and a working PCB.

You still sell some of the items, right?
Did you create the BOM?
It's outdated unfortunately.. Some part numbers doesn't exist.
Also the price has gone up like 20%, so you can tell it's been a while since it was created

Any help appreciated for this build.
96 pages of info seems overwhelming and confusing.

 

[[silent:arts]]

You still sell some of the items, right?

Yes. The PCB and the PSU transformer.

Did you create the BOM?
It's outdated unfortunately.. Some part numbers doesn't exist.
Also the price has gone up like 20%, so you can tell it's been a while since it was created

My BOM is pre RoHS and from 2007 and wouldn't help anyone.
You will learn a lot doing your own BOM, it isn't really that hard.

 

[abecedarian]

Silent:Arts,

I cant believe its been 7 years since my LA2A was fired up!  Glad this project has had success.  I'm really busier now and don't have time to do the things I always want to do.  I'm eyeing mine and knowing it needs new tubes and calibration, I'm afraid I'll need to deliver it to my excellent tech for service.  Anything I should tell him? I'm assuming the schematic is all he'll need. My memory is crap...  :-[

I was always curious as to hoe one made this a true stereo unit without matching TB4s?  I'm planning on using this for a blues album in mixing soon enough.  Hope all is well with you!

 

[[silent:arts]]

I'm not sure if I understand your question correctly.
Why do you think it needs new tubes? Only because it is 7 years old?

 

[Gearlust]

Gentlemen, may I present you the [silent:arts] D-LA2A:

it was not easy to fit the two channels in a 2U rack, but with a little care it worked:

it was my first self designed double sided PCB, and my first Tube project.
I'm glad everything is working

I have had problems with gain over "7" (may be this grid stopper thing), but I changed the gain pot to a 22K log in series with a 75K resistor to get an easier to adjust gain range (still 26dB gain - enough for a compressor / limiter).

hope you like it (since this LA2A is NOT ptp) :twisted: :green: :green: :green:

Im a decade late but This looks beautiful, you guys still make this.

 

[Gearlust]

I wish someone can make these in 1u racks. Kinda like audioscap d3a for la3 clones

 

[andow]

I wish someone can make these in 1u racks. Kinda like audioscap d3a for la3 clonea

Even a 2U case is kind of small for an 8 tube unit. I guess it could be done in theory, but it would get so hot that you'd have to leave a lot of space for ventilation above and below. Plus, the heat would really stress components and shorten their life span...

You can still buy the PCB from Volker in the white market, btw.