New Drip Electronics La2a Build Thread...

Well folks I am sure that due to the incredible web interest in the DIY aspect of the famous La2a compressor, it is worth posting here the progress of my now pending build. Any prices quoted will be in Australian dollars unless otherwise noted.

Basic Overview:
Choice is simply to build point to point or use a pcb. If you've done p2p before you know it's ok if you follow some basics but a pcb just makes it so much quicker plus the results are excellent. The pcb will cost a bit more but time is important so I have elected to spend cash to save time.

1. Board and two T4B (one fast and one slow) units are ordered from Drip using the later Version 4 Drip Electronics pcb.
2. 3RU rack case is ordered today also from Altronics. Wholesale price is around $70.
3. Bill Of Materials almost completed and then it's time to start getting some bits while Drip get their bits on their way.

This will be a hoot methinks. Let's see how that 'opinion' evolves with the project. These things do sound spectacular.

Cheers to anyone else also keen to have one of these in their setup.

Mully


Well folks I am sure that due to the incredible web interest in the DIY aspect of the famous La2a compressor, it is worth posting here the progress of my now pending build. Any prices quoted will be in Australian dollars unless otherwise noted.

Basic Overview:
Choice is simply to build point to point or use a pcb. If you've done p2p before you know it's ok if you follow some basics but a pcb just makes it so much quicker plus the results are excellent. The pcb will cost a bit more but time is important so I have elected to spend cash to save time.

1. Board and two T4B (one fast and one slow) units are ordered from Drip using the later Version 4 Drip Electronics pcb.
2. 3RU rack case is ordered today also from Altronics. Wholesale price is around $70.
3. Bill Of Materials almost completed and then it's time to start getting some bits while Drip get their bits on their way.

This will be a hoot methinks. Let's see how that 'opinion' evolves with the project. These things do sound spectacular.

Cheers to anyone else also keen to have one of these in their setup.

Dude that is so cool. We want photos.  Are you going to paint the case white ? or maybe cream to make it look like it's been in cigarette smoke for decades

Ok time for an update.

Case arrived last week and is standard flat pack for those who have built with them before, you know them as boring but functional. A good choice though for this pending audio gravy maker.

Negotiations have been underway for a while with another builder (his is completed) who has some parts I hope to purchase from him... some valves, transformers and special mojo caps.

If these negotiations go well, it is just the output transformer that I'll need to hunt down. Sowter option is good but hope to find something in Oz... can only try.

Ok, the bench area has had a face lift (tidy up more like it) so we are pretty close to getting construction underway... err, once the boards arrive.

Also now thinking about the reverse laser print trick for the face panel.... the resolution and options it provides are brilliant. Anyone here done it on any DIY?

Cheers for now.

If by "the reverse laser print trick for the face panel", you mean printing on the back side of clear stock, it works great. I've done a lot of proto control panels that way. I have a big roll of clear vellum that I use. I always cover it with a piece of plexi. Another good way is to buy some "trophy" plexi that has a thin black (other colors too) layer that is then laser etched.
That's what I use now for all my control panels.
Are you thinking about the "dijon" caps from Mojotone?
They also make an oil and paper cap. Some like them, I didn't have good luck with the Sozo yellow caps, the Mojo's look about the same.
I prefer the 716 Sprague Orange Drops (the 716's have the copper leads). Not exactly "botique" price wise, but I've always had good luck with them.
Just my .02.
Good Luck,
Tom

Update: PCB arrived yesterday and it had been dropped along the way giving it a nice flare in one corner. Won't affect operation at all but was slightly disappointing given the boutique nature of this board.

Gregory from Drip though was more than helpful and communicative about the issue and me as a buyer am happy with the result with an immediate replacement board also offered.

Can finally start the build I think as I'll keep the one I got... oh, and I have another CNC machine on it's way to contribute to this project... and the others to follow.

Cheers.

Hey Millzy! Hope you are well mate.

Yeah the board got split a bit fibreglass wise but operationally is fine and for general info... the milled wooden box was dropped as it reduced the price by $25US so I can understand the reasoning. The resulting packing effort definitely does not look after the board and Gregory is looking at adding an extra layer of wrap. We regularly send packages all over the world with Pure Tone and no way would I have sent this board like it was sent to me but it is a learning curve I am sure for Drip who I have to say are VERY positive about getting things right and certainly a great mob to deal with, even it is only Gregory. Not sure if there is more than he...

I hoped to lay things out in the case tonight but had a blown PA power amp and FOH box to fix... got them fixed though I am very glad to say.

LA2A related update: have bought output transformer (2 actually.. will have one to sell) from eBay which was unexpected bonus along with a standard input transformer from the same seller. Also near to closing a deal for a custom input transformer and loads of other parts surplus from another helpful Drip builder. Won't save a load of dollars but gets all the hard to source stuff sorted bar one valve which is a no brainer anyway. Looking at WES Components for most other required bits I don't already have.

The input tranny on the LA is known to be slightly fully unusable so the modded one I'm also getting tames it down a bit to give you a more usable range.

Will do CAD layout hopefully next week in prep for new mill so the harder to do holes like IEC and VU will be nice and simple.

PS: thinking about the Drip 47 valve pre amp after this... Gregory says it is a monster and I don't have a 'superb' valve pre... just the usual cheapies. Hmmm....

Cheers mate! Hope your new boutique mic has arrived!!!!

Hey mate the possible pre might have to wait coz the Drip project keeps getting help up by work... taking a while.

Ordering some parts tonight though so that's good news.

Get the cook all good so you can get onto one of these... gonna be mega through the JLM!!

Mully,

Is there a one stop shop to get all the parts or do you HAVE to search out all the parts?

I'd be interested in building one... but I can't spare the time or energy to search out parts.

Any tips?

best,
mike

Yeah Mike the parts sourcing is quite difficult. Mouser or similar makes it easier but you may get some bits out of stock etc.

I spent the whole of last night sourcing most of what I needed from one supplier BUT I did already have transformers and 3 of the valves. The 7 pin valve socket is the next fun find to resolve. In the Drip forum too some kind soul has posted a Mouser parts order ready for you to send in.. really handy and generous.

To be honest, the choice you make in some particular parts are pretty crucial and making those decisions and sourcing the parts to supply those decisions may kill a few hours for you... but it is all part of the fun... no really.

The VU also is an interesting choice to make as you have a few variable to choose between.

Go for it I say. Droddey's excellent demo of his unit helped make me decide.

Hey cool Mike... I've been distracted by mine coz of the new CNC machine... a good distraction to have though.

Hope to get panels drilled and mounted by end of next week... see how we go.

Cheers!

Mully


Good news update... have secured a Solen capacitor for C5 which is a little exciting... bit hard to find in Oz in the preferred value I discovered... but eBay came to the rescue.

Couple of mildly odd bits to source and we are nearly ready for final PCB loading plus rear panel layout is nearly decided as my input and output transformers will be external and not board mounted. The fun continues...

You are really geeking out on the electronics when you call capacitors buy brand name... LOL ! Makes me want to build a kit. Humm... I do have a microphone fet head amp kit in the hold... all I need is a capsule and shell.

Yeah fair call on all the above.

I did look at a lot of the pics available of old La2a units and because I'm old (40's) have worked on a lot of gear from the era and have even used one carbon resistor from my stash of decades old stock (that I removed from units) just for posterity sake. Very sad I know but there is something also about the mojo of this type of gear...

I'm running a custom wind input tranny from Sowter to get a bit more useful gain out of the Drip too... The C5 choice I'm sure is open to some conjecture but I can see a case for choice so I'm kee for the Solen. They're known pretty much too for crossover caps.

Frank you need to get that thing built fella! And Droddy I will be happy to get mine sounding as good as yours... it sounded excellent. How are you now with the VU? Is the JLM unit ok?

Brownian noise?

Interesting... one thing about them is they are less accurate (typically). You can measure a bunch of the same values and get quite a swing. Would be interesting to see their performance under signal conditions versus their contemporary counterparts.

My theory in this build is that allold valve gear I ever messed with was all carbon resistors and it sure sounded cool. Good enough for me. :)

Update: pcb standoffs and some other bits arrived today including the Solen cap(s)... got an extra one. Off four wheel driving this weeekend and next week is long hours building a laser tag centre so the build will be on hold for a week or so.... unless I start sleep walking coz I give it a lot of thought each night. ...yeah, sad I know.

"The carbon resistors I received are all metal film which made me smile to myself."

Are Carbon resistors really hard to find? They are still listed in lots of catalogs... are they just not actually in stock?

I have a box of tens of thousands of surplus Carbon resistors... but my vision is such that it is unlikely I will ever find what I want in there. :-)