dynaco A25 buzzing trouble

[craig]

Hi, when i first noticed a problem with my A25 one of the woofers was not responding at all, i pushed on it gently while it was on and it came back to life, but didn't resolve entire issue, because now on volumes above low it buzzes, didn't used to do that, i took woofer out put it back in at a different angle thought it was better but while playing it today i noticed it again, are they ruined ? it's made me depressed.

[Horswispr]

Not too depressing. If the problem is with the woofer, you can just score a used one on eBay for maybe $20. Don't pay more than $30. Just make sure you get the correct one, one that matches the one you have. Usually, it's a SEAS with "horns," sometimes called the "star" woofer. Could be a SEAS "roundie." Or if you have Scanspeak Dynaco A-25s (with the port above the tweeter) make sure you get a Scanspeak woofer.

[craig]

Not too depressing. If the problem is with the woofer, you can just score a used one on eBay for maybe $20. Don't pay more than $30. Just make sure you get the correct one, one that matches the one you have. Usually, it's a SEAS with "horns," sometimes called the "star" woofer. Could be a SEAS "roundie." Or if you have Scanspeak Dynaco A-25s (with the port above the tweeter) make sure you get a Scanspeak woofer.

[craig]

Seems to be half a dozen types of dynaco A25 woofers hard to find one that's really a match, if its slightly off i take it the roll over will not match ? I have 3 other A25 woofers and none seem to match, even the rubber surround is ever so slightly different, sigh i guess i wish they could be repaired as is.

[dynaco_dan]

Seems to be half a dozen types of dynaco A25 woofers hard to find one that's really a match, if its slightly off i take it the roll over will not match ? I have 3 other A25 woofers and none seem to match, even the rubber surround is ever so slightly different, sigh i guess i wish they could be repaired as is.

Hi there

There is at least 3 different physical Dynaco 8 ohm 10" woofers in the system, possibly more.

There is definitely 5 or 6 or more different variations of the actual A-25 model speaker system.

Left and right of center tweeters, vent above tweeter, vent below woofer, different grille cloth frames, wooden and

hardboard with cutouts, and of course the different Seas and Scan drivers.

Recently a USA member came forward with another A-25 variation, caps fastened also to the tweeter magnet, massive amount of staples holding a rare metal

vent cover mesh, rather than the typical black plastic one, a 3 position switch, rather than the standard 5 position, different value resistors, and

his friend has the same identical pair.

There is the round Scan and Seas and also the horned Seas woofers.

Removing a round woofer requires chiseling some wood where the horns should sit, if installing a horned Seas woofer instead

of a round basket, in the recess.

As a side note, Dynaco only ever supplied the horned woofer version as OEM warantee replacements.

As Horsewispr said, a used one can be bought for just a few dollars.

Care should be excercised in supporting the frame so that the shipping support does not press on the rubber surround.

A shorting strap would be a very good idea also, at least for a woofer.

Dynaco originally used a plastic fitting that looks just like, an electrical blind end connector, without the metal crimping insert.

They inserted one in each woofer hole facing the cardboard packaging which was folded to wrap around the woofers.

This would only work with a lighter aluminum woofer and cardboard or use plywood with a heavier woofer.

This allows a space of around 1/2" so that the surround has clearance from it's front.

I have some original woofers and their wrapping material, which I will photo soon and post it here.

You do need to identify the version you have though.

You have had the woofer out of the enclosure, please take a few front, side and rear woofer photos, including paper stickers.

Do not consider buying a brand new replacement version as it isn't the same driver.

Beware, some sellers try to say that their 4 or 15 ohm Seas woofers can be used for Dynaco speakers, not so.

These were used in B&O speakers and possibly others.

Modified 20110621 8:33 PM

Modified 20110705 10:17 AM