bennattj
New Member
I have a pair of KLH Model 32s with a burnt-out voice coil on one of the woofers (thank you Lady Gaga and my inability to stay below what I knew was the maximum volume), so they're currently upstairs collecting dust (while I enjoy the Model 17s I picked up to replace them).
Recently, I called a local audio repair shop that claims to specialize in vintage gear to ask about fixing a minor rattle in one of my 17s. The tech gave me serious pause when he said, "We'll just replace the woofers and tweeters with modern high-efficiency drivers if needed."
That red flag stopped me from dropping off the 17s, but it got me thinking: why not let someone go ham on the busted Model 32s? Then came the bigger realization—I’d essentially be asking a general repair shop to custom-design a speaker from scratch, and I'm not confident they have the design expertise to pull that off.
So, if I decide to take on this resto-mod myself—replacing the woofers and tweeters and designing a custom passive crossover—how monumental of a task am I looking at? Or is cutting my losses, and trying to sell them for <$100 probably my best option?
I have a basic understanding of Thiele-Small parameters (i.e. I know they are important and that's about it), and I know crossover design is critical (especially since matching an 8-inch woofer means finding a tweeter that can cross over fairly low, around 1.5–2 kHz).
A few specific questions for the brain trust:
Recently, I called a local audio repair shop that claims to specialize in vintage gear to ask about fixing a minor rattle in one of my 17s. The tech gave me serious pause when he said, "We'll just replace the woofers and tweeters with modern high-efficiency drivers if needed."
That red flag stopped me from dropping off the 17s, but it got me thinking: why not let someone go ham on the busted Model 32s? Then came the bigger realization—I’d essentially be asking a general repair shop to custom-design a speaker from scratch, and I'm not confident they have the design expertise to pull that off.
So, if I decide to take on this resto-mod myself—replacing the woofers and tweeters and designing a custom passive crossover—how monumental of a task am I looking at? Or is cutting my losses, and trying to sell them for <$100 probably my best option?
I have a basic understanding of Thiele-Small parameters (i.e. I know they are important and that's about it), and I know crossover design is critical (especially since matching an 8-inch woofer means finding a tweeter that can cross over fairly low, around 1.5–2 kHz).
A few specific questions for the brain trust:
- Driver Selection: Is there a way to select a reliable woofer/tweeter combo based on specs, or is buying and testing multiple physical drivers the only way to get good results?
- Measurement Workflow: Do I measure the drivers mounted in the cabinet before designing and building the crossover network?
- Internal Damping: What should I do with the original fiberglass insulation? Should I retain the original fill density, replace it with modern polyfill/denim insulation, or adjust the fill amount based on the new woofer's parameters?
- Step-by-Step Process: What is the proper sequence to pull this off? What acoustic/enclosure measurements do I need before choosing drivers, what parameters matter most for this cabinet volume, and what measurements do I need to take to design the crossover network?
