I am tearing apart the body parts of the fantastic sounding AER Compact mobile. The guide is for the 1st generation version, there is newer generations, so please verify with AER or your regional distributor on potentially different specs or replacement approach.

Haven not been able to find a lot of information on the amplifier on the internet, so I decided to give it a try. The result is rewarding, I can tell you!

The amp comes new at a price point of approx. USD 1,900 to USD 2,000 (after taxes). Try getting a used one and replace the batteries, if necessary. It sounds almost as good as the Compact 60 II (which I own in a 220 V version - which, living in the US, is not as good as owning a 110V - and, optimally in a mobile variant ... thus, this guide..)


The batteries we need as replacement. Those I found in my beloved AER which I just a few days ago bought used. So - no guarantee that those were not already a replacement for what was delivered by AER originally in the new device. I think they were original since they so nicely fitted into the compartment and looked as if never touched.
  • The batteries we need as replacement. Those I found in my beloved AER which I just a few days ago bought used. So - no guarantee that those were not already a replacement for what was delivered by AER originally in the new device. I think they were original since they so nicely fitted into the compartment and looked as if never touched.

  • I ordered the UN7-12 Lead Acid batteries new from The price in the US was less than USD 50 (in October 2015) with shipping to NYC included. Not bad, in particular compared to what I heared from the original manufacturer on what a battery replacement would cost (easily north of USD 300, with labor and two-way shipping added)!

  • The batteries are 12V with 7Ah. Note that I have seen information on the internet that the device would use two 6V Panasonic batteries with higher Ah, put together in series to get the 12V together necessary to run the device in mobile mode. Not in this case!

  • In our case, we already have the 12V, so they should be lined up in parallel to add up to 14Ah.

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The handle needs to come off to get access to the inner chamber.
  • The handle needs to come off to get access to the inner chamber.

  • Those screws are a real challenge! They are very hard to take out, so you better have a very robust Philips Screwdriver. There is 8 of them.

  • Once you take them out, it is very easy to take out the plastic handle and you get access to the chamber that hosts both the speaker and the batteries.

Great information. I bought my amp from new many years ago now. I wasn't using the amp outdoors any more and my batteries were dead anyway so I thought I would remove them completely and not replace them. I didn't know how it would affect the sound but i figured it would certainly make it lighter. I followed every step but when it came to removing the back panel to get access to the battery housing holding screws I had trouble getting it free. Once I finally forced it free I discovered that a capacitor had stuck solid to the board holding the back panel. Consequently the only way to get the back panel off was to rip the capacitor away from its housing....I have a gig in 3 days now so now I have to try to repair in time :)

justgeorge121 - Reply

  • Since my amplifier dates back to the early 2000's, the soft front with the AER logo came off easily, providing access to the grille. It was not glued or otherwise attached.

  • To take off the grille, you need to unscrew the four screws in the four corners with your Philips screwdriver.

  • This is how the amp looks like once once the Grille has been unscrewed and taken off.

  • Please note that the speaker is very fragile, in particular since the tweeter is built in its center, so please be very carefully handling it going forward!

  • Note: In my version of the amplifier, there is a bass reflex pipe on the right and a hole without such a pipe on the left.

  • You can probably also see the handle is also taken out on the left side of the chamber.

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  • You can (hopefully) see the size 8 locks on top of the long distance holders the come from the back of the chamber.

  • Those need to come off, but only for the part that secures the black batteries on the top, very much right behind the speaker.

  • Since it is virtually impossible to remove the locks without removing the speaker, speaker needs to come off. Another four very well fitted Philips screws that need to come off around the front side of the speaker.

  • Please find a picture attached for the tool I found in my treasure tool chest. Brought it from Germany.. "It's because of the metric system, you know.."

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  • The back side panel of my AER Compact Mobile. When I bought it used, it only worked on 110V - attached via normal power cable. The batteries would not charge (indicator LED did not turn on at all). So, I decided to tear it apart and find out which batteries were mounted to finally replace them and make live music!

  • There are seven easy to remove (in my case) short black screws that you need to unscrew to remove the back panel.

  • Very good German engineering, the panel comes off completely in one piece and slides out nicely from the amplifier body. Nice!

  • I uploaded an image of the screwdriver I used. It is important that it is robust and of good quality. Not so much for the screws we just took out, but for all later ones, where you need to take the deeper screws out of the massive wood, you better do.

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  • The back panel with all electronics has come off nicely.

  • As you can see, there is four screws on the black back of the speaker compartment which you need to attack in a later step.

  • I am showing it here so that you can prepare the tool, it is not yet time to take them out. First, we have to remove the carrying handle and the from grille as well as the speaker.

  • Please make sure you get a tool that helps you (In german this would be an 'Imbus', a small one)

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  • To get the light color wood battery holders off and to finally take the batteries out, you need to unscrew the top three of the long distance holders that are accessible from the outer back of the speaker chamber.

  • Please remember that in a prior step, the counter locks have been removed, so those should come out easily.

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  • Once the wooden holder comes off, the batteries come out and you can easily and softly unplug them and take them out through the handle hole.

  • It is easy to plug in the new batteries (red is red is +), (- is - is black) and to put them back in.

  • The picture of the battery. Note that there is two (2, dos, dois, dwa, due) of them in the device. No point in just replacing one..!

  • Have fun charging and enjoying some 4 hours of 'unplugged' acoustic music... you might run into me on the downtown NY subway.. pardon my playing, but enjoy the sound of the amp.. it is simply beautiful and worth price and replacement effort..

Hi, is this ok for the aer compact 60 - the version that can be powered only AC (with no batteries)?

I've read on the net that many people have buzz problems with a 'do it youself' battery.

Does your amplifier buzz?


Alessio biondi - Reply


To reassemble your device, follow these instructions in reverse order.

3 other people completed this guide.

Carsten Koscher

Member since: 10/09/2015

161 Reputation

1 Guide authored


Hi! If I've got the AER Compact 60 mobile II, have you got any suggestions on portable batteries to power it after it runs out? And is it possible to upgrade its batteries so it lasts longer?

KEN music - Reply

Thank you so much for this! My Compact Mobile 2 has been left dormant for about 9 years (I also have the early 2000s model). This guide is EXACTLY what I needed and so clearly explained along with the photos. Perfect!

Chuck Clarke - Reply

Hi, thanks for this great article! Would you tell me how much do the two batteries weight?

Is it ok for the aer compact 60? I'd use it as external battery.

Alessio biondi - Reply


Do anyone has a copy of the SERVICE MANUAL for AER COMPACT MOBILE 2.....

there something wrong in my Aer....

IF YES please send it to


Victor Omedes - Reply

Thanks Carsten this is very helpful. I do have one @x!F however. You say "Very good German engineering". I have to say I don't think they've thought through the implications of this degree of difficulty in replacing batteries. Even in the comments on this post there is an example of a purchaser who hasn't used the mobile capability for 10 years because they've run up against this difficulty. Very few people are going to go this amount of trouble, OR pay someone to do it. As the word gets out the end result will be that the product dies. The trade off between sound quality and price/convenience is swinging radically in favour of cheaper and more convenient products - albeit not as good in sound quality. But how much does it matter when the main use of these amps is on the street?

Tony Cusack - Reply

Hello, I have to change the voltage converter right before the batteries, after the fuse and the current input.

Anyone can tell me where to buy this? The inscription is erased, is anyone can make a picture of it otherwise?

Thanks a lot

Gaëtan Damoiseau - Reply

And here I was thinking that I was the only one suffering. Great article explaining exactly what I needed to know. I only ever use my Aer60 Compact Mobile indoors now so i do not need the battery facility. Will the amp work if I remove the batteries thus making the amp lighter?"

justgeorge121 - Reply

Hi, I live in the middle East of England, and I want to buy a second hand of AER mobile amplifier (Battery rechargeable) If anyone want to sale the AER mobile amplifier, please contact me : Thanks

Chun - Reply

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