Replaced blown woofer in an A/D/S L620 gen 2. It's not a robust as the other!

Sep 23, 2018
Bought a pair a of metal grilled A/D/S L620's know one cab had a blown woofer. I had ohmed out the good one to satisfaction, and bad one indeed was dead, maybe blown voice coil, etc. Bought the exact same part number woofer from ebay, and upon firing up my NAD amp noticed the right speaker needed me to advance the balance control to 1 o'clock for both speakers to sound about equal. I will try other methods like swapping speaker leads around, swapping the rear terminal/crossovers, etc. to see what gives. Anybody out there have any plausible explanations for what I'm seeing, rather hearing! I realize that's what the balance control is for, but all flat is how I grew up to understand how the setup should be. Thank you...this site is tremendous by the way!!!


New Member
Oct 5, 2015
Sofia, Bulgaria
Check the connection polarity of the new installed woofer - must match the old one. Sometimes, depend of the crossover and overall speaker designs, drivers are connected with reverse electrical polarity . You need to follow the original design. Aged crossover elements or woofers itself can be reasons for the unbalanced sound too.

About us

  • What’s Best Forum is THE forum for high end audio, product reviews, advice and sharing experiences on the best of everything else. A place where audiophiles and audio companies discuss existing and new audio products, music servers, music streamers and computer audio, digital to audio convertors (DACS), turntables, phono stages, cartridges, reel to reel, speakers, headphones, tube amplifiers and solid state amplification. Founded in 2010 What's Best Forum invites intelligent and courteous people of all interests and backgrounds to describe and discuss the best of everything. From beginners to life-long hobbyists to industry professionals we enjoy learning about new things and meeting new people and participating in spirited debates.

Quick Navigation

User Menu

Steve Williams
Site Founder | Site Owner | Administrator
Ron Resnick
Site Co-Owner | Administrator
Julian (The Fixer)
Website Build | Marketing Managersing