Magnavox D8443 Power Blaster Upgrade

[Lasonic TRC-920]

OK, so, unlike most of my threads were I toil away for days, week, months and years before posting. I will be posting as I go, ignoring all reasonable suggestions and stumbling along making huge mistakes and costly repairs....

Now with the "Legal department" out of the way....here we go...

Many of you saw and commented on this thread "Questions about the Magnavox D8443" and saw that I planned a big project around it...

The radio I will be starting with is this one...

It's in average to good condition



To begin with, the plan is to replace all speakers...

First, the stereo woofers with these Lucky / Lasonic 5.25" out of a TRC-918, 4 ohm
They are a little dirty, but that's ok.



The center speaker will be replaced with a white Lasonic 8" 4 ohm from a 931 to be used as the sub.
I will be getting this speaker from member SLO when we get together at some point. If for any reason that doesn't work, I will purchase a "Subwoofer" specific speaker for this project.

The goals of this build are pretty straightforward...to make this thing HIT as hard as it looks. To make the center speaker act like and sound like a subwoofer.

That isn't going to be easy, from my subwoofer building experience, it can be hit or miss when it comes to enclosures, porting or sealed. The real subwoofer numbers for an 8" speaker are 0.93 cubic feet, using a 3 inch diameter port, 9 inches long. Even gutted, I'm not sure there is a cubic foot of space inside this radio.

One of my ideas....

The D8443 is very shallow, see it pictured here with the TRC-920



So I thought, why not fatten it up a bit...and add a middle section be be part of a center enclosure to give me the interior space to comfortably achieve 1 cubic foot of subwoofer volume.



AMP POWER!

I have been using this little amp as a test mule for all kinds of projects.

Class D amp, 15 watts x2 or 30 watts mono'd with built in subwoofer bridging, 10v-18v DC power, headphone jack in and volume knob. $9.00 each, free shipping from China or $14.00 plus shipping from Parts Express on eBay



Thinking of using 2, one mono'd for the sub, one in stereo for the woofers and tweeters.

Add Bluetooth and DONE!

Well, not really, because I want to keep some of the features on the unit like the FM, volume, bass, treble and I'll add a sub volume knob which, like everything else in my life will complicate the whole build!

But we will start with the sub enclosure and see if I can get the cabinet to hit like a 1989 Toyota Mini Truck!

HERE WE GO!

 

[blu_fuz]

Ohhhhhh yeah, make her sing!!!!

 

[im_alan_partridge]

Good luck with the project mate, this list of parts and just reading your 8443 questions thread is giving me some potential ideas for my own 8444

 

[trippy1313]

Yes!!! Here we go!!! I like the idea of a middle spacer section.

Somebody grab me some popcorn please.

 

[MyOhMy]

 

[jimmyjimmy19702010]

The mega build has begun!

Looking forward to seeing what you can achieve sonically with the inbuilt constraints of utilising a thin, plastic case as a resonance box.

You're definately the man to overcome these challenges and create an awesome piece of kit.

Good luck with the project Chris,

Show that Maggie who's boss!!

James....

 

[Radio-Active]

Please sir, give me hope for my "sentimental box", I will always love my PowerPlayer. But it needs to be The One in my house again.

 

[T-STER]

<-----Pulls up at seat next to Mom. Share the popcorn please this is going to be a good one...

 

[Lasonic TRC-920]

Thanks everyone....I have a project on the workbench that I need to finish up and then I will open this thing up and have a look. I will see if I can get video of the process.

The mega build has begun!

Looking forward to seeing what you can achieve sonically with the inbuilt constraints of utilising a thin, plastic case as a resonance box.

You're definately the man to overcome these challenges and create an awesome piece of kit.

Good luck with the project Chris,

Show that Maggie who's boss!!

James....

Thanks James. I maybe hitting you up for some technical information or part suggestions should I hit some walls since you have built some "From Scratch" blasters.

Please sir, give me hope for my "sentimental box", I will always love my PowerPlayer. But it needs to be The One in my house again.

R.A., it's going to take some time to figure this out....lets "Hope" it can be done!

 

[Northerner]

Definitely watching this one

 

[Reli]

Don't forget to put some real tweeters in there!

I don't think those Lasonic speakers are capable of producing good mids, let alone highs. Those surrounds are just too soft. So if they can't produce good mids, then you should at least give it some highs, LOL.

Consider the TRC-920 for example, it doesn't produce very good mids IMHO. So if it didn't have good tweeters for the highs, that box would suck.

 

[Lasonic TRC-920]

Don't forget to put some real tweeters in there!

I don't think those Lasonic speakers are capable of producing good mids, let alone highs. Those surrounds are just too soft. So if they can't produce good mids, then you should at least give it some highs, LOL.

Consider the TRC-920 for example, it doesn't produce very good mids IMHO. So if it didn't have good tweeters for the highs, that box would suck.

100% on new tweeters, not sure what size can fit in there, but that is a must.

I'm not sure what will happen with these Lasonic speakers. You could be right. The 918 actual has good solid bass, but I might have to go with a mid range speaker. But since I have them and they are free, I will try them out.

 

[jimmyjimmy19702010]

The sound of speakers has as much to do with the equalisation as it does with the cabinet dimensions and design. Neither of these previous parameters are applicable to this new installation.

Your Lasonic drivers (2) should work well as mids. The tweeter sensitivity (loudness) will be the tricky part as to balance with the dominating output of an 8 inch driver powered by its own mono amp.

 

[Reli]

Those Lasonic speakers have rolled surrounds, made of foam or cloth or something. And everytime I've had a box with those kind of surrounds, the mids weren't as good as my other boxes with regular paper cone edges. But, the bass will be good.

As for tweeters, anything will be better than those stock pizeos. Do they even produce any sound anymore?

 

[Reli]

Another thing that would look sick is if you painted all the little nooks & crannies between the speakers. While masking off the chrome pieces, of course.

 

[MyOhMy]

<-----Pulls up at seat next to Mom. Share the popcorn please this is going to be a good one...

Tell me about it! I've put my soft slippers on along with my very baggy but comfy ol' cardigan - I'm well settled down for this one.

 

[trippy1313]

Thanks everyone....I have a project on the workbench that I need to finish up and then I will open this thing up and have a look. I will see if I can get video of the process.

You're such a tease!!!! Start this thread but not starting to work on it???

TEASE!!!

 

[restocat]

Good luck! I have a working parts box , PM if you need anything.

 

[Lasonic TRC-920]

You're such a tease!!!! Start this thread but not starting to work on it???

TEASE!!!

Yeah, this one will be a long and drawn out process...stay tuned.

Good luck! I have a working parts box , PM if you need anything.

Thanks brother, if I hit a wall I will hit you up!

 

[kennerithmcguire]

What if you were to build the back half of the box out of mdf, In order to get the thickness/depth but used the back half of the case to skin the unit? Very similar to your design but it would allow for better acoustics plus keeping the original look and feel.

Using bondo, or fiberglass to blend the back to the front of the original case...in essence the inner box is made from wood slightly smaller than the actual casing.

Hope this makes sense, I love this kind of Mod!