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Ugg. 
I am so close I can taste it. 
Okay so I have read (and reread) this thread and have taken days (then weeks) off to meditate on it and work on other projects hoping I would come back to it and it would hit me.  Hit me it has not.
I have been reluctant to ask for help on this thread cause i figured somewhere, someone had already posted a problem similar enough to mine and that I just needed to find it but I haven't been able to.  I am sure it's in here somewhere since i am so close and I think I remember someone posting with a similar problem but just can't find it and I give up and need to ask for help.
Or at least a point in the right direction.
First things first; this has been my favorite project to date.  By far.  I have learned soooo much reading this thread and building this thing.  It feels like ten projects in one awesome one.  Thank you Volker and everyone else; it's been a trip.
Onto what's up;
So I have only built one side using  Edcor in and out (wsm 600/15k and vice versa) as well as using Kenetek's T4B.  I am currently saving up for Sowter in and outs but might just grab some more Edcors until then. 
I have also implemented the 25k pot mod using the required 75k resistor and 12ay7 tubes.
I have power and all my voltages are pretty on.  I ran shielded wire throughout except for lights and what not. 
When putting music through I have gain and not really compression or it feels like too much and it's drenched in low frequency I would even say there's a high frequency cut off.  Everything sounds like its in a reverb tank.  Vocals are almost non existent.  They are in the background.  It feels like a grounding issue but I have every ground in place, my star ground looks good and i have run wires to the front panel and sides.  I also have zero noise or hum.
Audio comes through and the bypass works perfectly.
The gain works but I have to crank it and reading this thread that should not be like that at all.
I would really appreciate it if someone could point me in the right direction.  Maybe its a wrong resistor value somewhere but they all look right after checking and rechecking a bunch of times.
Here are some pics of the inside.
EJ6b0Lol.jpg

In the above pic the bh7 and ay7 are in the wrong places which I noticed right after taking it. I have swapped tubes since then and still my problem persists.

Here's the side without the tubes or T4B in.
aumZEMSl.jpg

and during daylight
cTIImfOl.jpg


Finally, just look at how awesome that looks, this needs to get working.  ;)
LuSdyFEl.jpg

Please help me make it sound awesome too.
 
Rocinante said:
Everything sounds like its in a reverb tank.  Vocals are almost non existent.
[/quote

Just a wild guess: the other channel is inverted at some point so there's some sort of "stereo without mono signal" combination?
Sometimes pluging a stereo jack about the mid-way in causes an effect that reminds your description...

But as said, just a wild guess...
 
Hi there!

I have a problem with my build. I just put my new Kenetek's in this unit and started to calibrate it only to see i have a problem with my meters.

Im feeding a 0.775V signal into it and when the unit is IN and i crank the gain i can hear the signal. My meters jump right to -7 and stay there. I can hear the attenuator working cause when i turn it the signal gets weaker. But my meters show no movement no matter if i put them on GR or VU.

The only way i can get my meters back down to -20 is to tap them. Are they broken? I have the resistor on the positive side and ive checked trafo wiring etc.
 
darkus said:
Hi there!

I have a problem with my build. I just put my new Kenetek's in this unit and started to calibrate it only to see i have a problem with my meters.

Im feeding a 0.775V signal into it and when the unit is IN and i crank the gain i can hear the signal. My meters jump right to -7 and stay there. I can hear the attenuator working cause when i turn it the signal gets weaker. But my meters show no movement no matter if i put them on GR or VU.

The only way i can get my meters back down to -20 is to tap them. Are they broken? I have the resistor on the positive side and ive checked trafo wiring etc.

I had the same problem and fixed it when I redid (tighten) my switches and relays. Make sure your vu meter wires are going to going to the correct location on the switch as well as the relay wires. After I super secured everything and followed Kingstons diagram perfectly it worked fine. Those relay connections need to be tight. Also make sure to adjust the meter via the trimmer. 
 
No luck yet  :(

I checked the wiring, its exactly as in the compiled info PDF. I tightened all my wire terminals. VU meters are so loose that they are rattling.

The unit passes signal and i can hear it compressing, i even tested it with a drumloop. But still my meters jump to -7 and stay there until i tap them. If i apply very little gain and keep the meter below -10 i can see it bouncing with the beat. but once i switch the meters to gain reduction its all -7 again.
 
It was two bad 12bh7s!!!!

What are the chances I bought two bad bh7s?  Pretty good apparently.  After getting weird measurements at r117 and the comp displaying the same behavior on both sides I bought another bh7 off ebay and stuck it in and...  success! !!!  And yeah  it sounds every bit as great as I imagined.
I was really starting to get depressed over this, but I'm pretty f***ing happy now.
Thank you Volker its been a trip. Seriously despite the hang ups and hiatus this hss been one of my favorite projects to date.
Okay back to playing with it some more.
 
And im done. The problem was in those custom meter cards i printed, the needle touched them just a tiny bit causing them not going anywhere past the halfway. ...

If i didnt try to customize the meters this could have worked right off the bat! Damn. Anyways i got it calibrated, by luck the 1st channel was pretty spot on from the start, now they both sound amazing and track perfectly in stereo!

Edcor trafos and Kenetek matched T4B's.

So excited. Thank you Volker and everyone else helping! Now im off to get that pm670 finished
 

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Hi everyone.

I got a weird issue with my build:

Zener (or "neon light") gets good voltages (64V) on the left channel. Right channel gets only 6,7V.
I tried to change the R28/470k but no bacon :( The voltage before the resistor is ok (346V).

Incoming voltages to R33, 34 and 35 also good.

Any clues?

 
jipsu said:
[silent:arts] said:
wrong Zener?
or wrong / broken / not trimmed RV4.

Zener same on both channels as is the trimmer (all parts via the US-bom).

Will test the trimmer later...

Trimmers tested (attached to the board), equal values on both channels...
 
jipsu said:
jipsu said:
[silent:arts] said:
wrong Zener?
or wrong / broken / not trimmed RV4.

Zener same on both channels as is the trimmer (all parts via the US-bom).

Will test the trimmer later...

Trimmers tested (attached to the board), equal values on both channels...

Right. After doing some testing (and blowing up the Zeners) i changed the R28's and Zeners and now both get a steady 63V. So that one is solved (although i still have no idea what was wrong in the beginning). Live and learn...
 
Ordered my PCB and started to get all the other goodies ordered for this project! Very excited!!!! The only real question now is where to source the T4B's, and do I get the fast or slow? I record and producer heavy metal music so I would need the compressor to be "material correct" for what I typically produce. Hopefully I will only need to post about this since I plan for the build to be completely flawless in every way and fire up perfect on the 1st go! HAHAHAHAHA
 
Ordered a 62V 5W Zener from Mouser.  Turns out the leg diameter (1mm) is too large to fit the board.  I can't seem to find any 62V 5W diodes with smaller leg diameters.  Any suggestions?
 
Barton said:
Ordered a 62V 5W Zener from Mouser.  Turns out the leg diameter (1mm) is too large to fit the board.  I can't seem to find any 62V 5W diodes with smaller leg diameters.  Any suggestions?

Add small "studs" through the board and solder the zeners sideways.

 

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I have well working build but vu meter leds is small problem. Have connected them to relay 5V source. Second channel vu leds swapping from on to off. Like 5min on and then some minute off and back on. What this mean? First channel leds working well.

Solved

Soldered resistor before the led.
 
OK- I have been building my DLA2A and I need a few parts that are not on the US BOM. I have been trying the smart search but coming up empty for the last couple of bits I need. C8 100n, what should the voltage be for this cap, NE2/DS101 what is this part? not finding a description through the schematic. I also need the heatsink for the 511-L7805CP, I do not know how to research the part number. C109, and C209 where out of stock with mouser at the time I ordered all my goodies so I am wondering if I can find the Wima caps some where else, or just use an alternative piece like and orange drop or something.
 

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