picked up a allen and heath sr416 today

[doulos24]

I'm starting a new thread picked the mixer up today and I'm going to start a small blog of cleaning it up and doing some upgrades I have schematics I need to print and hope some of you here can help me with selecting how to get the most out of this great board

[doulos24]

here is a pick of the mixer

[doulos24]

power supply pics

[doulos24]

I have a question? should I beef up this power supply if I'm going to change the opamps in the desk? looks like the tl072 draws about 3ma and most replacments draw like 5 to 7ma a chip I'm looking at replacing the tl072s in the preamp section and leaving the tl072s in the eq section as I like the sound of them my goal is to get a great sounding single channel and then duplicate it through the desk, but I dont want to fry the psu either or is there more of a drop in replacment for the tl072 that will have better preformance and similar enough current draw I'm overlooking?

[doulos24]

I'm off to get the schematics printed so I can tape the pages side by side I got all but the psu schematics I also ordered 60 gold plated machined dip sockets cant wait to get started got some videos of the guts about to load on youtube as well

[doulos24]

I got all the schematics printed cept the power supply. I'm going to ask allen and heath for that hopefully they still have it, so for now im going to start with the input channels. These schematics look hand drawn on seperate pages ,so I'm going to do some photoshop an piece the pcb and input schematic together pics comming soon

[doulos24]

[doulos24]

ordered 7 caps to recap the psu today I'll have pics when the work begins

[doulos24]

caps came in today and ive already replaced the 2 big ones on the daughter board I still have 5 more to go and I need to get some heatsink compound to reatach the transistors but I'm having fun

[doulos24]

power supply recapped


I'm gonna go power it up now woohoo it works i didn't blow anything up

[moley]

I love threads like this!

Makes me want to open up my old Soundcraft 500 and start recapping. Maybe start, like you did, with the power supply, then master section.

Keep those photos coming.....

:D

[doulos24]

thank you for the post! I just figured no one cared about my lil project and I was just wastin my time bloging about it, but I intend to take more pics as more parts come in

[moley]

but I intend to take more pics as more parts come in

Please do!

I'll definitely keep an eye out for this thread. Looking forward to the next installment!

:D

[Pat]

Nice thread.

[doulos24]

ok looks like I hit 3 snags while working on this board 1 all fader screws are stripped so I have to take the faders apart from the bottom and either clean them that way or drill out the holes for diffrent faders 2 the faders are 90mm and I cant find any replacments and finally the xlr connectors have to be unsoldered one at a time to get the boards free

will that stop me? ha hardly I unsoldered some stuff and pulled a channel to look at It and added some pics

[doulos24]

some pics of progress?

[doulos24]

ok so now I'm figuring out what I don't need what I do need what I'd like and what I care and don't care about

first what I don't need as odd as it sounds I don't need aux sends and I don't need the 4 mix busses I don't need crappy unmovable faders either

what I do need I need 16 mic pres and line ins I do need direct outs
I do need usable faders and summed to stereo left right

likes: I'd like to have an eq section that's semi parametric using 4 pots and 2/3 TL082 chips

I care about the sound and I don't care about the looks missing sections and holes where things use to go won't bother me

[doulos24]

ok sunday update for anyone following my thread I pulled all 4 of the busses and I stripped the boards I now have 4 extra faders extra switches pots and jacks not to mention 4 times the leds for the meters if anything goes wrong with the mixer I'm covered. now I'm thinking of going a lil crazy and of course some pics

[doulos24]

I now have room for 4 exta pots "extended eq" an extra switch per channel plus room for 8 extra pots and 4 switches in the mix group section. I'm thinking this is a prime place to install a buss compressor what do you guys think?

[babalou]

Originally Posted by doulos24

some pics of progress?

do you have any parts that you wanna sell i have a sr-16 mixer im looking for the faders a 4 pcb boards

[doulos24]

I'm lost on the last part your looking for faders or input strips? my faders screws are all stripped so if I drilled them out you'd have to retro fit them to get them to work again. I just pulled the 4 busses and stripped all the parts off of them and I'm keeping all the input strips so I don't think I'm much help with parts unless you need some spare aux pots jacks switches or knobs etc sorry

[doulos30]

ok so I changed names but last night was a horrible night rainy nasty etc so I thought I'd mess with this board some more



In pic 2 "below" you see the side of the mixer it's really no fun you have to unscrew and desolder the xlr to free the channel strip
I have 8 of them unloaded getting fitted with mill sockets and a order of 24 tle2072's on the way
at 65 bucks for just opamps I think doing 8 channels at a time is best




here you can see the 8 I left in. oddly enough even with 4 auxes removed and 8 input cards the the thing still works lol

[The Real MC]

I used to own one of these.

I resurrected it by repairing the power supply, fixing some ground busses on some of the channels, and contact oxidation on some of the insert jacks were rendering some I/O inoperative. Really decent sounding board for the era (early 1980s). Never modified any channels. I made some recordings of live shows and they came off really good.

Definitely worth the restore effort.

I graduated to the GL-2200, have a 32 channel and 12 channel frame.

[doulos30]

just a quick update

8 cards out getting opamps swapped and recapped



found a way around the faders i was able to drill out the old faders with a dremel and get stereo 10 k fader to make mono 5 k ones



these fader feel pretty smooth and are a real upgrade to the old warn out ones

this is the fader law diffrence I can live with that thumbsup



***things left to do***

*referb project*

* working on making an order for the replacment caps
* still need to test a channel an fader
* need to figure out how to make the new fader screw mounts
* want to wire quick releases for the 16 xlrs

*diy mixer progress*

* have the mic pre schematic
* and the L/R amps picked
* working on the eq section
* and clipping/pan circuit

[doulos30]

waiting on a mouser order

ordered new pan and gain pots
as well as the caps to change out 8 boards

drilled and cut out the rest of the faders
desoldered 24 opamps and installed sockets
ordered 60 more milled sockets from china

should be back at it monday with the recapping

[BrianAbington]

I really like the old A&H boards. Its nice to know that the ones I've been looking at for starting my buisness that are that old are fairly easy to fix.


When I was in school we had a small practice mixing room that had one of the old wooden bodied A&H boards that each channel unscrewed and puled out through the top of the board. I loved it.

I am definatly following this project.

[doulos30]

make sure you get one with actual 100mm faders thats the biggest issue I have right now with this board it had 90mm faders and I'm going to have to waste a fader break it open etc to make a solid drill templet to retro fit the 100mm ones

[doulos30]

just a quick update

all 16 input faders drilled out
12 inputs stripped "48 opamps and 120 electric caps pulled"

waiting on my mouser order



all the stuff that had to be pulled out


installed all 45 milled opamp sockets I had left. nothing I can do now till mouser comes

ordered 16 replacment xlrs got cheap ones though lol

[oxide54]

whats in the "sunday morning", monday morning container? medication??

[doulos30]

smd parts I'm a bit pissed at mouser I ordered on a friday with second day air and they didnt ship till monday