707 crossovers in a 705

jghglofer

I happen to get my hands on a set of 707 crossovers and was wondering how they would fit in a pair of 705's. I just don't know if they match up

WLDock

The 705's have a 2800Hz & 100Hz crossover w/ 5" midrange & 5"x7" woofers.

The 707's have a 3000Hz & 100Hz crossover w/ 6.5" midrange & 6"x9" woofers

Given that the speakers are still in production and parts are available from Polk I guess I don't see the point. Whats wrong with your LSiM 705 crossovers? Or are you looking to keep the original crossovers in tack yet have a second set of crossovers to mod? I guess you could use the 707 boards or make your own. Are you planning to build with better components?

F1nut

Different circuits designed specifically for each model, so no. If you want to improve the 705's upgrade the crossover components.

jghglofer

I like the 705's just the way they are. but got a set of 707 boards and was just wondering. maybe I will start me a project.

rooftop59

jghglofer wrote: »

I like the 705's just the way they are. but got a set of 707 boards and was just wondering. maybe I will start me a project.

What exactly are you wondering? The 707s don't have better components, just different specs designed for different drivers and cabinet volume. follow F1NUT's advice...

But hey they are your speakers and your time and money, have at it!

WLDock

jghglofer wrote: »

I like the 705's just the way they are. but got a set of 707 boards and was just wondering. maybe I will start me a project.

Ok, your reply is a little vague however maybe you are saying that your goal is to use this set of 707 boards to modify them with better components in hopes of improving the 705's. The boards may or may not work depending on how far you go with the crossover mod. Some of the poly caps from Clarity Caps for example might be much larger and may not fit.

The best thing to do is to find a schematic but i don't think they were ever released. So, compare the 705 to the 707 crossover side by side to see what the component value differences are. You might have to measure the inductors as they might not be labeled like the caps, and resistors. Both speakers/crossovers seem to use the same topology so there might be minor component changes. However, there could be some changes here and there that one has and the other does not. You can modify the components on the 707 board to the same values as the 705.
Here are pics of the 705 crossovers.

jghglofer

@WLDock yes your right I did leave the table with out answering. my question was would the 707 boards sound any better in the 705's and that question was answered.
I am not going to mod the 705's like I said I like them just the way they are. the project will be to use these 707 boards in a build.

WLDock

jghglofer wrote: »

@WLDock yes your right I did leave the table with out answering. my question was would the 707 boards sound any better in the 705's and that question was answered.
I am not going to mod the 705's like I said I like them just the way they are. the project will be to use these 707 boards in a build.

Did you get the boards for free or super cheap or something? Because there are tons of DIY project plans out there. Money could be better spent towards the correct components for a given project.





https://www.audioholics.com/diy-audio/building-a-do-it-yourself-loudspeaker-design

https://www.popularmechanics.com/technology/audio/how-to/a3485/build-your-own-speakers/

https://www.instructables.com/id/How-to-Build-Custom-Speakers/

http://techtalk.parts-express.com/forum/tech-talk-forum/38661-the-speaker-building-bible

https://www.amazon.com/Loudspeaker-Design-Cookbook-Vance-Dickason/dp/1882580338/ref=pd_lpo_sbs_14_t_1?_encoding=UTF8&psc=1&refRID=YASC3M2YHPZ1PFQMB7ZY

https://www.amazon.com/Speaker-Building-201-Ray-Alden/dp/1882580451

http://projectgallery.parts-express.com/

https://www.diyaudioandvideo.com/Guide/BuildSpeaker/

http://speakerdesignworks.com/index_page_2.html

https://meniscusaudio.com/product-category/speaker-kits/

http://www.zaphaudio.com/

https://www.madisoundspeakerstore.com/welcome.php

https://www.css-audio.com/

http://www.troelsgravesen.dk/Diy_Loudspeaker_Projects.htm

https://www.youtube.com/channel/UCOuow_HIYmeaIqi42zVs3qg

https://www.diyaudio.com/forums/loudspeakers/

http://www.htguide.com/forum/forumdisplay.php?6-Mission-Possible-DIY

https://www.hometheatershack.com/forums/diy-speakers/

jghglofer

@WLDock I got them free

WLDock

jghglofer wrote: »

@WLDock I got them free

Nothing like free. Maybe you can find some cheap driver from the speaker buyout section at Parts Express that might work with those crossover points. Then, design a cabinet and build and fine tune. Might make for a fun garage, basement, etc speaker project.

sgmsmg

@jghglofer
I know it has been a couple of years but by any chance do you still have the 707 crossovers and would you be willing to sell them?