ADS L300C sound "dead"??

[CE Holden]

Hi,
I recently acquired a set of ADS L300C speakers, having been so enamored with my old pair of L200C's, but needing a little more "oomph" than the little 200s could handle. Having read mostly glowing reviews of the 300s, I purchased a pair on Reverb. I am quite disappointed. The 300s sound, for lack of a better descriptor, dead. Highs are very muted, no depth of sound, muddy, just terrible. I even looked on the back of the speakers to see if there was a tweeter attenuator, because that's what it sounds like to me. All drivers seem to be functional. I swapped them out and hooked up my 200s and the sound difference is like night and day. I did notice that the 300s appear to be a later version of ADS; they don't have the sticky dome tweeter (Braun?) that my 200s have. Are the later 300 speakers/tweeters inferior? Any mods I can do to open up the sound on these things? As they are, they are basically boat anchors.
Sage advice appreciated.

 

[Andyman]

I'll be refoaming a set later today, so I'll post some pics of the crossover and check out my tweeters. I'm a big fan of the L300s and certainly don't find them "dead" even with my iffy hearing.

I've had a set in my bedroom for a decade and they are probably the last speakers I'll sell due to their great sound and small size.

 

[avguytx]

I'm pretty sure those use mylar caps, from what I recall about opening mine up. But, I could be wrong. Do you have a DMM to check the tweeters? Also, you could pull a tweeter from your 200's and swap it with one out of the 300's and see what the difference is. No, they aren't the same tweeters most likely, but it gives you a baseline to work with. I have a pair of L300C's I use in the living room on the rare occasion we listen to background music and they sound great. Now upstairs, I have a pair of L1230's that I love. The tweeters have been to Richard So in AZ for a rebuild as the originals were dead and I'll probably send the mids to be done after this freaking snow goes away.

 

[Boston Tom]

Hi,
I recently acquired a set of ADS L300C speakers, having been so enamored with my old pair of L200C's, but needing a little more "oomph" than the little 200s could handle. Having read mostly glowing reviews of the 300s, I purchased a pair on Reverb. I am quite disappointed. The 300s sound, for lack of a better descriptor, dead. Highs are very muted, no depth of sound, muddy, just terrible. I even looked on the back of the speakers to see if there was a tweeter attenuator, because that's what it sounds like to me. All drivers seem to be functional. I swapped them out and hooked up my 200s and the sound difference is like night and day. I did notice that the 300s appear to be a later version of ADS; they don't have the sticky dome tweeter (Braun?) that my 200s have. Are the later 300 speakers/tweeters inferior? Any mods I can do to open up the sound on these things? As they are, they are basically boat anchors.
Sage advice appreciated.

Depending on the tweeter model might just need to clean and replace the ferrofluid in the tweeters. Not likely the crossover component ADS used high end caps in their electronics.
are yours the black brushed aluminum or the painted black model. 300 or L300c?
I have both and they have a nearly identical sound quality.
Good luck
BT

 

[wmgwizard]

Ferrofluid replacement will likely correct your issue, crossovers are rarely an issue in ADS speakers as they were "ahead of the curve" using high quality Mylar caps in a majority of their speakers.

If you are uncomfortable with the process reach out to AK member Richard So, he is a former ADS employee and restores ADS speakers.

 

[CE Holden]

are yours the black brushed aluminum or the painted black model. 300 or L300c?
I have both and they have a nearly identical sound quality.
Good luck
BT

They’re L300C models; black painted.
They look newer than my 200 series, with the logo as “a/d/s” instead of ads in blocks (if that matters).

 

[CE Holden]

after this freaking snow goes away.

I'm hip. Lucky to have power right now (after having been without for 36 hours), but no running water. I guess we can't have everything...
Speaking of fluids, I will look into replacing the ferrofluid in the tweeters. I did not know that was something that would ever need replacing or could even be replaced! If it looks like more than I can or want to deal with, then I will endeavor to get in contact with Mr. So.
Thanks for the help; I surely do appreciate it.

 

[Boston Tom]

They’re L300C models; black painted.
They look newer than my 200 series, with the logo as “a/d/s” instead of ads in blocks (if that matters).

Nice yours are the newer models aDs 300 were the earlier ones and had the brushed black anodized finish and also had foam surrounds which I need to replace on my pair. Glad the power is back on for you. Hope it warms up soon.
Cheers
BT

 

[Andyman]

I did the refoam today on my L300Cs and they sound fine. I didn't snap any pictures of the crossover because after I pushed away all the fiberglass stuffing I found the backside of a PC board that was screwed to the back. Digging all the wool out and unscrewing the board was more than I planned to do. I did find this in another L300 thread here and it might help. looks like it's a 6.8uf cap in the tweeter circuit.

 

[CE Holden]

Sticky ferrofluid, indeed...
Boston Tom, wmgwizard: Tweeter coils were literally stuck in ferrofluid muck (say, I'm a poet and....never mind.)
Very gingerly pulled them apart and cleaned out the coil gaps and bobbins. Ordered new vials of ferrofluid from Parts Express. I'll post an update once I get them back together. I had no idea ferrofluid was something that ever gummed up, but it makes sense (now).
Andyman, thanks for the schematics--those may come in handy yet!
Thanks for all the help, folks! Hopefully I can return the favor sometime!

 

[plugto]

According to Rich, the older formula ferrofluid had a tendency to gum up. I had him rebuild an entire L1290/2 pair. I bought them used to use as rear surrounds. I had a pair already in the front, and when running a pink noise signal for calibration purposes on volume in a 5.1 theater, they were 2 db lower than the front pair. I found that odd but sent them to Rich and it was the ferrofluid. He has videos on youtube where you can see the inside of the tweeter with the fluid. Check it out. Also it is not good for the skin, and makes a mess.
I have 6 pairs of the 300s, and was going to use them for height speakers in an Atmos system. They couldn't play loud enough to keep up with the 1290/2s. Then I found out from Dolby that ALL the speakers in an Atmos set up receive full bandwidth, full frequency signals. So the best set up is ALL speakers be the same size and make and model for the timbre integrity.
I did replace the 300s in my bedroom with a pair of CM5s. I was curious about the 24db slope crossover. They blew the 300s away. Extremely deep and wide soundstage, and with a copolymer tweeter not the sticky dome. Crystal clear sound. Years ago I had a pair of BA400s, and the copolymer tweeter was less clear than the sticky domes. I mistakenly assumed that copolymer couldn't go as high or clear.
I was wrong. ADS models that came later are extremely clear. Nice discovery for me. I paid 120$ for the pair. Better bass than the 300s too. I hope you contact Rich to get them done right.

 

[safebet]

I picked up a set a couple years ago to use at work on a little Advent receiver. One sounds quite dull compared to the other, seems likely the ferrofluid issue is the culprit. Thanks all for the info.

 

[plugto]

I picked up a set a couple years ago to use at work on a little Advent receiver. One sounds quite dull compared to the other, seems likely the ferrofluid issue is the culprit. Thanks all for the info.

Speaking of Advent. My first pair of real good speakers were the Large Advents. Sooooooooo good for cheap. Henry used the cheapest parts and got the highest playback and accuracy then any one else.Quite the engineer. Rich So just did surrounds on a pair for me. I just had to have the old analog system again. I wouldn't trust anyone to fix any speaker more than Rich. Over 30 years experience is hard to beat.





Testing them out with a few tunes on the old Ipod. My first decent receiver the Marantz 2030.

 

[CE Holden]

Replacing the ferrofluid was a cinch, and it brought these speakers back to life. I bought new fluid from Parts Express, and they came in two vial "dosages" for each tweeter. Hardest part was cleaning out the old gunk. Sure appreciate everyone's input.

 

[plugto]

Nice job CE!