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View Full Version : Altec 605A Duplex with N-1600-C found in garage! bass issue



po90260
02-12-2011, 08:09 PM
My Altec 605A Duplex with N-1600-C has been in a garage for 25 years. I only found one speaker and the plywood enclosure was too large and ugly. I removed the speaker from the enclosure to examine it. Looks OK, has black surround. Then I tested speaker on the floor connected to a 8 OHM receiver set on mono with bass turned up. I'm getting very little bass. Does the enclosure boost the bass? I turned the dial on the N-1600 but it didn't boost it much. I seem to remember it sounding better back in the 80's.

HCSGuy
02-12-2011, 08:24 PM
A Woofer sitting on the floor with no enclosure will have very little bass as the sound off the back side of the cone will cancel out the sound from the front of the cone. The purpose of the enclosure is to do something with the sound off the back - either absorb it or use the air motion to resonate the air in the port tube to produce more bass. Secondly, the enclosure helps limit the excursion of the woofer - without it you can easily physically damage a woofer. You need some box for your woofer, even if it is ugly...

1audiohack
02-12-2011, 08:29 PM
Welcome to Lansing Heritage by the way.

po90260
02-12-2011, 08:40 PM
A Woofer sitting on the floor with no enclosure will have very little bass as the sound off the back side of the cone will cancel out the sound from the front of the cone. The purpose of the enclosure is to do something with the sound off the back - either absorb it or use the air motion to resonate the air in the port tube to produce more bass. Secondly, the enclosure helps limit the excursion of the woofer - without it you can easily physically damage a woofer. You need some box for your woofer, even if it is ugly...

Thanks, I'll paint it or decorate it.

The box is 17x23x30 inches with a large vent (port tube?) on back.
Is there an optimal size?
Do they require the opening?

HCSGuy
02-12-2011, 09:38 PM
Generally, an enclosure's volume is optimized for the woofer that is going in it. Likewise, the port tuning is dictated by the woofers performance in that sized enclosure - if you downsize the enclosure but keep the opening size the same, your box performance will change significantly. If your box is an Altec box, you could remake it nicer looking, but should keep the volume and opening dimensions the same. If is a homemade box, all bets are off and you should look through this site's library for enclosure guides, solicit help from an Altec collector on the forum (I'm not one), or do a search for your driver and it will probably show up in one of the threads. Post some pictures and we can also give you an idea or two on the enclosure.

po90260
02-13-2011, 03:48 PM
Generally, an enclosure's volume is optimized for the woofer that is going in it. Likewise, the port tuning is dictated by the woofers performance in that sized enclosure - if you downsize the enclosure but keep the opening size the same, your box performance will change significantly. If your box is an Altec box, you could remake it nicer looking, but should keep the volume and opening dimensions the same. If is a homemade box, all bets are off and you should look through this site's library for enclosure guides, solicit help from an Altec collector on the forum (I'm not one), or do a search for your driver and it will probably show up in one of the threads. Post some pictures and we can also give you an idea or two on the enclosure.

I'll have to go with the 6.78819 ft³ box that I have. When I took the back off it had a rubber seal that has turned into a tar-like substance which I scraped off. I'm not sure what to reseal it with.

HCSGuy
02-13-2011, 04:15 PM
Try one of these for sealing the cabinet - If there are large gaps, you may need to do some repair or get rubber weatherstripping.

http://www.parts-express.com/wizards/searchResults.cfm?srchExt=CAT&srchCat=818&CFID=30048619&CFTOKEN=92280507

po90260
03-01-2011, 08:33 PM
Try one of these for sealing the cabinet - If there are large gaps, you may need to do some repair or get rubber weatherstripping.

http://www.parts-express.com/wizards/searchResults.cfm?srchExt=CAT&srchCat=818&CFID=30048619&CFTOKEN=92280507

I ended up getting rubber foam weatherseal self stick tape for $3.25


The speaker sounds awsome. The only problem is that I only have one.