recently acquired ar3's advice

[Guest]

hello, i am a newbie but will make this quick. i recently purchased a pair of ar3's. as is to be expected, the adjustment pots work only with much twisting and pushing, and then only while you push them in. what are the basic options to solve this? I would love to simply repair/replace them and keep them as stock as possible. is there any way to repair/replace them without going through the front of the speakers? thanks a lot.

[administrator]

The behavior you are describing is very common .. the pots have developed corroded contacts over time.

I was going to replace my pots in a pair of AR3's and a pair of AR3a's, with new units, but they replacements that I have seen are very low quality Taiwanese make.

So .. I took all the pots apart one night on the kitchen table and sanded all the contacts with fine sandpaper. You may need to flex the contact arm slightly in each pot to make sure there is good contact.

Soldered them back in, and they worked perfectly ..

Beware however, these pots will corrode again. I have been told by Stephen Tidwell at Layne Audio that the corrosion will occur relatively fast, (i.e. you aren't going to get another 20 years out of them!) but I'm not sure how many years you can expect before more cleaning is required. If Stephen reads this he may give you a rough estimate ..

Another option is to just find high quality replacement pots. I'm not sure where to find them, or if they are made by anyone in the US?? (The originals I think were made in Chicago.)

Mark

[stan461]

I purchased a set of pots from Layne Audio (appx. $7.00 each). They seem to work perfectly. I say seem because like yourself, I'm not an AR expert and am not "that" familiar with the sound. I saved the old pots and will fool around with fixing them.

In a 6 part article on rebuilding the AR3a in Speaker Builder magazine page 37 issue THREE:1998 , Tom Yaego states "I soldered little gold-plated pads (from pc boards) onto the contact points of the wipers, and I sealed the shafts with some thick grease". I'll try this and see what happens. Although I don't know why you need to seal the shaft (rust?).

This series of articles is excellent reading because it touches on every aspect of the AR3a's. As a blueprint for rebuilding - forget it!!!. Perhaps with more pictures and diagrams it you could actually go thru the rebuild. If you read the article you'll see what I mean.

[oldguide]

I believe the rebuilding "book" references this, but in case you missed it, be sure and put some contact grease on the pots, that will help cut down on the corrosion. The big box folks should have it in the electrical section.

[genek]

I believe the rebuilding "book" references this, but in case you missed it, be sure and put some contact grease on the pots, that will help cut down on the corrosion. The big box folks should have it in the electrical section.

If they didn't find grease in 2001, my guess is the pots have already failed again by now.