ADAM Active Studio Monitor schematic diagrams help

No response as of yet, I’ll probably have to do it myself.

Is 4 hours labour about right to change the ICEpower 250A no to fix the popping woofer issue? Seems like a lot to me.

It’s £240 labour and £117 for the part.

I’m assuming it’s not plug and play (I found the amp a little cheaper online) and requires soldering etc.
Sorry for not being clear.

Yes, I was asking if 4 hours labour is correct for 250A module replacement. I can source the part for £95 delivered in the UK to resolve the issue with the standby switch popping on speaker B. Perhaps I can give it to a suitable tech in the UK to install, assuming it is not something simple that I can do myself.

The issue with the filter module is a separate issue that again, I would hope a tech would be able to fix. UK tech recommendations welcome.

Assuming Adam repair UK won't send pics, I will post pics of the internals in about a week when I get the speakers back.

Thank you
Got my S3As back today. Here are pics of speaker A, the one with apparently the bad ‘filter board’ (green board in the second picture) causing gain mismatch between the two speakers.

To my surprise, there is seemingly no soldering required to fix replace one of the two ice power 250A modules. It looks like a 30 min job that I can do myself. 4 hours labour?! I might have to send a very angry email to Adam HQ… perhaps there is a calibration process required? Otherwise, seems like plug and play.

Please let me know if you need more pics. I will open up speaker B (the one with the faulty ice power 250A module) tomorrow to see if there is any difference or obvious problems.


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Pics of speaker B…. The one that pops on standby and apparently needs new 250A module.

I do need a way to know which 250A module to replace…


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Update - I took the pics and then put my monitors back up. To my surprise, the one speaker that popped when on standby didn't do it anymore! OK... maybe I was lucky and they... fixed it for free?!

I turn them on and clearly one speaker is out of phase with another - or at least one of the woofers on one of the speakers is.

When I solo them or pan music left or right, the speaker that pops has noticeably less bass, though both woofers are using. So I'm assuming one woofer is out of phase with the other.

This is exactly what happened 10 years ago when they were in warranty and came back from repair then. I sent them back to CImple Solutions (no Adam repair in the Uk back then) and they 'fixed' it, but it caused the above issue.

Again, can anybody recommend a repair person in the UK that could look at these?


Edit: please note the orientation of the blue & black cables from the woofer to the filter board in both pics. Now look at the red & black cables and the brown & black cables. These two pairs are flipped. It seems to me like they put at least one of them back the wrong way? Perhaps the black and blue should be also flipped so that all the cables are the 'opposite' on each side? Or, maybe they should be identical in both monitors? If anybody could advise before I start randomly tinkering, that would be great. I will try to see if the colour/polarity is written on the board itself.


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First thing I checked - coloured cables are plugged correctly into the +tive connection on green board.

HOWEVER I moved the tweeter and the ribbon is wired with wrong polarity. Blue is negative instead of positive (see + symbol on bottom of attached pic). So I will correct this and check each woofer.

So the Adam Repair people put it back 'correctly' without checking that the ribbon actually has the black as +tive.

I will also check on Speaker A for comparison as I don't trust anything anymore.

Edit: speaker A photo is added and black is marked “-“ in pen. So black is negative, correctly


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After removing/investigating the wiring on every single driver and investigating polarity, here's what I learned:

1) The ribbon-tweeter in speaker B is wired with the wrong polarity, as in the above post. The Adam repair person put it back together without comparing/noticing and as such the tweeter was out of phase.

2) The full-range speaker on both speakers is also wired out of phase - by default. Meaning, the black cable has to go to the +tive even though black is marked as negative at the woofer. Again, Adam repair put this back together with the coloured wire going to the connector marked +tive but this is wrong and looking at speaker A confirms this (also sounds very thin - I tried it. Less bass than NS10s this way!). I have also found a picture from of another user and it matches - black is +tive. This means 2 out of 3 of the drivers in Speaker B were out of phase when I plugged them in!

I have not messed with the sub-only speaker wiring (brown & black) and am assuming it is correct and in-phase with the tweeter and full range-driver in both speakers.

3) For some strange reason, the popping on speaker B has not happened since I got the speakers back, regardless of the polarity of any of the speakers!

4) There are 5 'secret' pots on the back of each speaker. These are covered with rubber bungs and seem to have direct access to functions on the filter board. These rubber bungs have been removed on my Speaker B - even before I sent them to Adam - and I have never noticed this. Confirmed with old pictures. I have a feeling these control high frequency and gain controls from directly on the filter board, bypassing the front control panel.

I've attached pictures of the filter board which corresponds to these pots. They are marked: Gain_HT / EQ_HT and EQ_SUB / EQ_TMT / EQ_MT. Could anybody tell me exactly what these do and how to calibrate them correctly? I wonder if this is really the source of my mismatch and has nothing to do with the filter board on Speaker A. Or perhaps Speaker A's are set incorrectly. I just want everything to be flat/whatever they should be from factory.

Many thanks,


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If you have a look at post No. 188, the third picture (IMG_188.jepg), you can see three capacitors, two blue, one black. On the left of the blue 22uF/63V (seems to be c146) there is some soldering and a black SMD transistor. The cap seems to be bend away.
The tech may have been searching for the fault there (they often fix things to be sure it can be done cheaply, without a new, expensive board. Then they mess something simple up again, so the customer get's back a faulty unit if he doesn't pay for the repair).
In this case it looks as if he did a quick, not permanent fix just to check, as this is not going to last long.

You should get that fixed in a professional way. New cap and a new transistor or at least everything soldered clean and flat.
These amps and filters in active speakers do not last for ever, simply because of heat and vibration. Same electronics outside the speaker, in a well vented case, will have a much longer life.
Look for other areas of quick and dirty fixing, very carefull, with a lens and lots of light.

I did not understand what these polarity issues are, but that and a quick turn of a pot would make the speaker look defective, even if it was fixed, electronically. Look at the pot's, search for marks. I don't think the wanted to readjust the whole system, so I would simply mark the right position when I disadjusted it on purpose. Not that I do such things, but I know what tricks this trade uses were I live.

Changing only an A250 amp will take about 15 minutes, if you don't use an electric screwdriver. Serching for the fault on the filter board may take longer.
Anyway, if the know these speakers, they know the faults. ICE and ADAM products are very reliable in having typical, known faults. So they usually know what is blown in what case. Many repairs are not based on cost and time, but value of the object they repair.
Hi - thanks for your feedback!

The board in post 188 is for Speaker B - that is the one with the 'bad' ICE 250A board not the one with the 'faulty filter board', that's Speaker A in post 187. Sorry, I know there's lots of information.

Speaker B has had work done in the past, by Cimple Solutions in the UK, before there was Adam Audio repair. Perhaps that's what you're seeing.
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it doesn't matter on which board the bend cap and "somehow" soldered transistor is, you should get that fixed. A bend cap may also be a sign of it failing. It then may be the cause for any kind of trouble, like blown parts, cracking, humming or time related on/ off problems.

If you have one "working side, compare the pot positions. Best is always to make good pictures first.

Without an electrical setup guide for correct output voltages, you may measure all speakers levels and a combined frequency response with a microfone. The pots adjust them playing together. You can not do that by ear.
If one unit is untouched and still adjusted correctly, you just have to match position of cabinet in room and microfone position while you measure. Then you compare curves and match A to B.
I'm pretty sure he is unable to do these things by him self, but to say so is usually considered rude.
So explaining what has to be done technically may actually show him this stuff is is more than he can do by him self.

Anyway, I feel sorry for this nice speaker that is so expensive to repair because once it was so expensive.
It is hard to find a repair option that takes into account the value of the used object. Which in the end will put this wonderful speaker in the dump.
Please don't feel that it's rude - I cannot solder or understand the electronics involved, I'm a producer / mixer, not an electrical engineer and don't have your expertise. I'm more sad that you said it will end up in landfill!!! I don't want that.

I've managed to at least get the speakers back to where they were and can continue to work. I opened up every woofer and now I understand more about the way the speakers/amps work. I'd never opened them up before. At least I was able to fix the polarity problem caused by Adam Repair. I no longer trust anything they say.

I came here mainly to ask for a good tech in the UK that could fix/inspect the speakers for me - that question still stands, please, I'm all ears if there are any recommendations. I'm also all ears if anybody knows a different forum/place to ask these questions if this is not the correct thread/forum.

Currently the speakers are operating 'fine'/as they were and there is no pop when Speaker B is switched to standby. I have lost a little confidence that what I am hearing is 100% as it should be, though.
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