LA2A finished and sounding fine. HaLA2Aluya brothers!

[Bluzzi]

Its been a long time since I finished anything, actually this is my second LA2A and although it took longer in time span it actually was shorter in build time.
I was more confident and kept my wire length shorter than first build.

No problems whatsoever with this one. Worked from first turn on. I'm really happy.

I used UTC A10 and A24, 12AY7 for V1 and 100K for R9 and R13 as per CJ. All my PS caps were 40uf.
I did not use variable caps for C4 and C14 but rather fixed ones.

If I were to change anything it would be to put the Limiter response pot in the front panel. I'd also eliminate the stereo pot section. XFRs are OK but if I build anymore I will use Jensen, Cinemag or Sowter on input at least.

I think the controls are straight forward enough to not need any identification. I like it as is.

Thanks to CJ and Cayocosta.

jim

 

[3nity]

Jim..it looks nice as all you projects!

 

[Nele]

Nice! Is that mounting panel steel or aluminum?
Any noise problems?

 

[Bluzzi]

3nity - Thanks for the compliment. You'll have to come over and try it one day.

Nele - Its aluminum. No noise whatsoever! I admit I was scared both times I built this that there would be noise. My first had "motorboating" that was fixed by tucking a wire under one of the caps in the turret board.

My second one is noiseless as is. My wiring was tighter and cleaner.

jim

 

[maxwall]

What was your total project cost ?

 

[Bluzzi]

About 2 pints of blood, a quart of sweat.

I don't have an exact figure but its about $500 to $700. Does it matter?

Sorry but I get a bit uncomfortable as cost varies for all these projects.

You want one? take a risk. Buy parts a bit at a time.

jim

 

[emrr]

I should know by now what that rack chassis is; off the shelf or no?

 

[drpat]

Lookin' great! I love the crusty old meter, and I wouldn't polish it up if I were you. That Sprague ATOM output cap is huge, did you sleeve the leads on that thing?

 

[Bluzzi]

Doug - I bought a bunch of 3RU from Tungstengruvsten a long time ago. They had not front or back panels.

Patrick - I love those meters as well! you can't take your eyes from them when they are lit! The cap is huge I know. A bit clumsy to put on and I saved it for the last part to go on. I did use insulation on my first LA2A but on this one I felt more confident and left it naked. Its soldered on very well and won't budge.

I have to also say that there is a romantic quality to all this P2P wiring and using old VU meters. I wonder what audio has gone through that meter?

The great thing is that I actually used my LA2A and now I have 2 to use.

I may customize it later on and bring the limiter adjust pot to the front. On my first one I have it on full blast but on this one I actually reached back and played around with it. I liked a few settings as I was turning. My advise to anyone building one is to put it on the front.

jim

 

[MartyMart]

Great, very much the "old nuclear power station" look
I like that a LOT !
Marty.

 

[Bluzzi]

[quote author="MartyMart"]Great, very much the "old nuclear power station" look
I like that a LOT !
Marty.[/quote]

'was wondering why the meter was glowing in the dark!

jim

:grin:

 

[AnalogPackrat]

Nice build, Jim. You certainly weren't cramped in that chassis!

 

[Bluzzi]

Thanks AnalogPackrat, its all I had at the time. Actually these are made by Schroff as I found out recently. They have a hinged front panel option I also found out.

jim

 

[maxwall]

Is that Allied power transformer quiet ?

those are considerably cheaper than a Hammond 369JX, don't know why there is a big gap in the price, makes me curious.

 

[Bluzzi]

maxwall - Yes its the Allied. Its probably made by Hammond for them. No noise whatsoever. But again in the LA2A the power XFR is pretty far from the I/O XFRs and connectors.

jim

 

[guitarbill55]

Nice job Jim. :thumb: :thumb: It must feel great to have two done and matched up. Are those the tent sale T4B's? Looking at yours makes me wish I had used a larger layout for mine. BTW I used the allied transformers for mine and have not noted any issues with noise, hum or power output. I'm going to post my first one on this forum as I just got it working.. It's twin is still in labor!

:thumb:

gb

 

[SSLtech]

[quote author="maxwall"]Is that Allied power transformer quiet ?

those are considerably cheaper than a Hammond 369JX, don't know why there is a big gap in the price, makes me curious.[/quote]

The Allied has no split/dual primary, so it's 110/120V only, the Hammond has 100/110/120/200/210/220/230/240 as primary voltage options. It's also rated VERY slightly higher in terms of VA, but if you're building a US-Only LA-2a, the Allied is the less-expensive option, of that there is NO doubt!

They're perfectly quiet, both mechanically and -in the completed unit- electrically. I also believe that they're manufactured by Hammond to the same standard as the 369JX, but made as a volume batch using a slightly shorter body, and with only 110V/120V primary windings,

they were the standard power transformer for the BLOO LA-2a's, and the Hammonds were supplied only for those kits going overseas, at extra charge IIRC. The quality is the same for both.

Keith

 

[Bluzzi]

Thanks gb. yes it feels really good, especially when nothing goes wrong and it works from the get go. My first one had motorboating and I panicked. But once I moved 1 wire it all went away. I made sure my second one had shorter wire paths. It paid off.

I still love P2P, I guess I'm a romantic at heart

Yes the T4B was from the tent sale! Please post your picts of your build!

jim