Boston Acoustic HD7

[kevin30127]

Thanks for any information you may have on this. Looking for the crossover schematic for the Boston Acoustic HD7 loudspeaker. Thanks again.

 

[Hybrid fourdoor]

Do you have access to the crossover board? Looking at eBay listings, it looks like a 2nd order with a resistor, probably to pad the tweeter. But we would need to know the values to get an idea of the crossover frequency.

 

[system7]

Yup, second order on both filters, you'd think.

Probably 2mH followed by 6uF on the bass. 3.3uF followed by 0.3mH on the tweeter. That 4R could go in a lot of places. 3kHz crossover I'd guess.

7" polycone Vifa-type bass with foam surround. Tends to rot.

 

[xrk971]

I have HD5's and XO looks very similar. Foam surrounds also rotted.

 

[kevin30127]

Upgrade Crossover

Thanks guys. Was wondering if you thought it was worth upgrading the crossover components? Speakers sound pretty good for there age. And there will be a reform in the near future. I can build boxes and choose drivers but the crossover part for whatever reason has been difficult for me to get. I can wire a schematic but cannot figure out what goes to what on this board. The round inductor has 250mh in the center and the square one has 300mh under it. Any help would be appreciated. Thinking of upgrading the crossover for fun. See what happens. Thanks.

 

[system7]

You need to trace the crossover before you do anything.

It can't be far from the below:

 

[Ron E]

I wouldn't bother with anything other than replacing caps with Mylar or polypropylene.
3.3uF and 6uF mylar caps are pretty cheap
https://www.madisoundspeakerstore.com/carli-capacitors/carli-mylar-3.3-mfd/
https://www.madisoundspeakerstore.com/carli-capacitors/carli-mylar-6-mfd/

Polypropylene caps only slightly more expensive:
https://www.madisoundspeakerstore.com/solen-capacitors/solen-3.3-mfd-fast-cap-400v/
https://www.madisoundspeakerstore.com/solen-capacitors/solen-6-mfd-fast-cap-400v/

Don't be fooled into thinking that spending 10 times as much will give you better sound.

 

[kevin30127]

Thanks guys. This is exactly what I was looking for.