Roadside JBL L100t Pair

[grey]

I owned a pair of L80T and L80t3 speakers at the same time and was able to do a direct comparison between them. The t3 version had much better midrange and highs that were less bright the the T version. The sound was more refined. There wasn't much difference in the bass, if any. I also have T and t3 variants of the L20 and like the L20T better. I think the reason is due to the bass port being located in the front (the t3's is in the rear) which gives more fullness to the bass and lower midrange and the L20t3 sound quality is much more dependent on speaker placement.

I remember the tech sheets having different external dimensions between the 100t and t3. I've only owned the t3 so far. Not sure if there is an internal volume difference to be considered. Everything that I've seen on the 100t to t3 crossover modification feedback has been positive.

 

[OldJBL]

I remember the tech sheets having different external dimensions between the 100t and t3. I've only owned the t3 so far. Not sure if there is an internal volume difference to be considered. Everything that I've seen on the 100t to t3 crossover modification feedback has been positive.

The t3 series had smaller cabinet dimensions for every model in the line compared to the T versions.

 

[crybdr]

This is the crossover network. Not a PCB but more of an old school 'breadboard'. I've researched a bunch about it.

The vocals on these speakers with my source and built in EQ flat (Yamaha AV-50 receiver) all sound really 'loud/harsh' at mid high volumes. If I nudge the 2.5khz slider down a bit - the harshness goes away and it feels comfortable all around. I am no audiophile, but what I'm reading says it could be partly due to capacitor age.

Capacitors: All have likely drifted over 40+ years and should be replaced.
Resistors: Wirewound ceramic, don't drift unless damaged visually inspect - don't replace.
Inductors: Don't drift unless damaged visually inspect - don't replace.

I can work on this board, I can get some lacquered wire to keep it legit if any needs to be changed out. Just don't have $$ to throw the whole kitchen sink at these speakers at the moment.

Am I right to focus on capacitors and leave the resistors and inductors alone for now?

 

[maxhifi]

Am I right to focus on capacitors and leave the resistors and inductors alone for now?

Yes. And the yellow film capacitors are also fine. Just the three nonpolar electrolytic capacitors should be replaced.