I want to stack my OLAs (Advents), would appreciate some guidance

[OP Music]

So right now I've got all four speakers wired in to the A and B spots on the back of the receiver, such that all the ports are taken. The highs and mids sound great, seamless like the two-way design is meant to be. My problem is that I'm not getting a whole lot of low-end out of them. Is this typical of OLAs? I have the bass EQ'd on the Marantz, it is all the way up. I'm still not able to get the bass response from the speakers that I'm looking for.

Also, I thought I would mention, I was playing the speakers last night in this configuration, and the receiver got really hot, I could smell something burning so I turned the receiver off. I am playing them this morning in the same configuration, and it seems that this is not an issue...

Any suggestions/information is appreciated, thank you!

 

[stereofanboy]

Earlier in this thread was a warning against cranking the bass with that configuration. You're playing with fire and may soon start a fire. Hope your receiver survives.

Check to be certain of polarity as reversing can cause bass cancellation. If you have correctly observed external polarity, a woofer or woofers may be wired backwards inside the cabinet.

Advents that old have certainly needed refoaming. Perhaps they weren't reinstalled properly after a foam job.

 

[jberger]

My first suspicion is that one (or more) of the speakers are wired out of phase. Double check the wiring on both ends of all four cables, and make sure that + on the receiver ends up at + on each speaker. Out of phase woofers will cancel out bass frequencies in odd ways.

 

[Blue Shadow]

make sure no strands have moved to touch anything on the wire ends. If you have it cranked and crank the bass and put on the loudness you will be over driving your amp. Don't do that. What amp? How recently serviced? That 2325 should have no problem if you don't try for concert hall levels. If you do you will burn up the amp.

 

[c5corvette]

I for one would recommend connecting just one pair first. Properly wired should deliver the bass response. Play at louder volumes to monitor overheating issue. If all is well, then connect second pair in parallel. Double check for proper wiring.

 

[OP Music]

So I just checked the wiring, and one of the speakers was wired wrong, good call guys haha. It sounds way better!

 

[ranch 22b]

Good to hear that you got it figured out.

 

[toxcrusadr]

Zilch, God rest his soul, is turning over in his grave.

 

[E-Stat]

Hey guys, I have two pairs of Original Large Advents (utility cabs) that I would like to power with my Marantz 2325, I just want to make sure I'm doing this right. From most everything I've read, there seems to be a consensus that powering the Advents in parallel is the way to go. Will my Marantz be able to handle the low impedances of the Advents when stacked and wired in parallel?

You definitely want to run parallel and position the upper pair inverted for a pseudo D'Appolito arrangement where the tweeters are closest together to minimize comb filter effects. HP ran them that way in his review back in '72.

While the nominal impedance is 4 ohms, they do drop to 2.3 ohms in certain regions. I ran mine with a Threshold Stasis amp that had no trouble originally driving my reactive Acoustat electrostats.

 

[OP Music]

I don't know what I'm doing wrong, but the low end is just not right... The kick drum just doesn't have any of the low frequencies that it should have. I have them in the inverted position, and I have the two speakers on the right wired to the Main speaker ports and the left side wired to the Remote speaker ports on the receiver.

 

[OP Music]

Here's a couple pictures for you guys

 

[Old Guy8]

Don't understand why you wire that way? Left speakers go to left side. And right on right side.

Have amp turned off for changes. I would wire bottom left speaker to main left on amp or receiver. Bottom right speaker to main right on amp
Then top left speaker to remote left on amp. Top right speaker to remote right of amp.
Does that make sense to you? Both left speakers on left side. Both right speakers on right. Has to make sense to you before you do it!!!

 

[OP Music]

Don't understand why you wire that way? Left speakers go to left side. And right on right side.

Have amp turned off for changes. I would wire bottom left speaker to main left on amp or receiver. Bottom right speaker to main right on amp
Then top left speaker to remote left on amp. Top right speaker to remote right of amp.
Does that make sense to you? Both left speakers on left side. Both right speakers on right. Has to make sense to you before you do it!!!

Good call OG! I have no idea what I was thinking when I wired these up! They sound better hahahaha thank you

 

[OP Music]

Good call OG! I have no idea what I was thinking when I wired these up! They sound better hahahaha thank you

Alright guys, in my enjoyment of how good they sounded, I may have bumped them a little hard for one of the woofers! The top left woofer is now "buzzing", particularly on the more bass-heavy songs, or at louder volumes. I took the grill off, and the foam looks fine around the woofer.

 

[Old Guy8]

OP,
I'm not a speaker expert. My opinion, don't assume you killed that woofer. Could be wires touching the speaker cone or the speaker cone could be sagging with age. Are you sure the foam surrounds are pliable?
If surround in good and pliable, could try something else. You could turn off stereo first. Remove the woofer. Look for wires might be touching cone. You could rotate woofer 180 degrees and reassemble. Be carful not to cross thread or over torque screws in the old wood. Try music through the speaker again. See if still buzzing.
If still buzzing. Possible they were not aligned well when last refoamed. Or foreign material got down in the voice coil. Or you over drove them.
Others may have better ideas. Wait for them.

 

[Ross6860]

I couldn't find any jumper cables long enough (on the internet) to do the job. Also, I think my speaker wire is too fat of a gauge to simply put jumpers on them. Any suggestions? The speaker terminal connectors don't seem to be the easiest things to connect two wires to.

Use ring terminals. You can get them from any auto parts store. You will need a $5 set of wire strippers to squeeze them (you should have one around the house anyhow). The Advents (and many speakers of the same era) posts are made for them. "Yellows" should allow two #12s to be inserted. If you are running huge wire like #10 or #8, you may have to use wire nuts to make the splice to smaller gauge to make the speaker connections.

I have two pair of NLAs and the volume increase running them stacked (upper speaker inverted, as has been mentioned) is pretty phenomenal. The NLA has no lack of bass, so that should never be an issue. A receiver much smaller, and just as old as yours ran them just fine as reasonable levels.

Enjoy.

 

[toxcrusadr]

That buzzing speaker, if it's an upside down one, try turning it right side up. Spider sag or misalignment may be causing it to barely touch the magnet, and it may clear up if you switch gravity around.

Also make sure you're wiring them all in phase. I thought when you said they sounded weird, phasing was a possible culprit. Sounds like you fixed the problem though by changing the hookup.

 

[OP Music]

Hey guys, the roommates were putting pressure on me to move the Advents, so I figured I'd do a little test on them again. Played the top two in inverted configuration (same as before) and the culprit speaker was still acting up. My pops and I could hear a clicking noise coming from the top left speaker (we both decided that it didn't sound like a blown speaker), maybe more like a contact problem as you guys suggested. Inverted the speaker once again (so that it was playing right side up) and the clicking noise disappeared. However, the woofer still did not sound right and I did notice there was a little separation between foam surround and the masonite ring. I think this may be causing the weird "loose" sounding bass, but I am no expert. I imagine that's something I could fix pretty easily with a little glue and some time. What do you guys think?

 

[Ross6860]

Large Advents are acoustic suspension speakers and need a sealed cabinet to work properly.

The clicking you heard may have been that woofer voice coil bottoming out. The air in the enclosure acts as a spring and has a significant effect on the woofer operation.

Foam for these speakers is pretty affordable. I'm no expert re-foamer and I have successfully re-foamed a couple sets of woofers. Take your time, do some research, and I'm sure you can do it. Clean all the old foam, and again, take your time. The glue does not set fast and you have plenty of time to get things situated.

You may be able to repair what you have with speaker surround glue. If you can get access to the backside of the surround, make sure you get enough in there to get a seal. My Advents are metal frame and I'm not familiar with the construction of the Masonite ring woofers.

Good luck, and not to overstate the point but these are decent speakers and should have plenty of bass, and volume. Most complaints are about the tweeter on these speakers, the woofer is pretty darn nice, even today.

Don't give up on them unless you want to shell out considerably more cash for something "better".

 

[JLange2010]

Just chiming in for encouragement - I refoamed my NLA's about a year ago. It was the first time doing anything like that. I was intimidated by the inverted foam ring, the test tone, so many things. But I spent about an hour researching how to do it and maybe 1-1/2 hours actually doing it. No problems at all, it is really quite simple. The hardest part was having enough patience to scrape all the old foam off of the various parts. They are now happily playing under another pair I picked up in order to do the stacked thing.