So I've picked up a Magnavox D8443 and it really isn't rubbish like some people say it is,it can definitely use some improvement with some modern and more efficient speakers but this is a good and loud sounding box that can be fiddled with to sound quite sweet and well balanced. So in my quest to make this box step up to this next level I really could use your help.

First off is the radio sounds really nice with the radio but when I use the tape player I run into a problem. I've looked through some of the posts here that say use the line out on this box and run your signal in through that. However the problem is that this seems to require quite a bit of drive from the source and even when I use one of my headphone amplifiers I can't really get around this so I mainly use a tape adapter and one thing I notice with the tape adapter(I need to double check if this is also the same with the line out)is that it doesn't sound as good as just straight radio. I have a problem with sibilant treble that just runs away and gets way way too piercing. It almost seems like as I feed more signal into the tape adapter into the deck that the sound becomes more compressed and ugly sounding while still at the same time not reaching the same volume level as when the box is just playing through FM radio. The volume difference isn't much but its there. I'm trying to figure out what I'm overdriving. Am I maxing out something literally in the heads of the tape or is it further down the signal path? Some songs sound great whereas others sound bloody awful. It sounds like I'm trying to shove 5 gallons worth of sound into a 2 gallon bucket. Basically I'd just like to get the same volume and headroom from playing from an outside source as I do from the radio's internal tuner.

Another problem I have,and I have to investigate this more thoroughly,is that sometimes when I press the Play button the box fails to turn on. Sometimes it does,sometimes it doesn't and sometimes when it does work it'll power off randomly. I'm not quite sure what causes this. Is there some switch that is depressed when the Play button is depressed that activates the power? If so then perhaps this is dirty... Its not a huge deal but still I'd like to know what it might be.

But down to the nitty gritty. I notice that when I turn the bass up the center woofer starts to distort if the control is turned much past 2 in the positive direction. I take it the amp driving this speaker simply cannot keep up with the demand of the woofer and is thus saturating,right?

So I want to replace the current speakers with higher efficiency modern speakers so I can create more volume and require less load on the op amps themselves and thus giving me some more headroom. I've heard the two side speakers are 5" in diameter and that the center speaker is 190mm or about 7.5",correct? Could someone recommend me some good replacements for both? Would it be possible to stick an 8" subwoofer in place of the middle woofer or would this require too much current draw to power regardless if its dB sensitivity rating is higher than that of the original woofer?

Are the tweeters that are situated above the left and right channel speakers of the piezo variety? I'm pretty sure I could replace this with proper cone style tweeters,correct?

How much of a pain is it to take this box apart? I see the screws on the back but is there anything I have to worry about when cracking this box apart? Either way I hope that through installing more efficient speakers the op amps won't have to work as hard and thus hopefully the center one especially won't be driven to saturation so quickly.

As a complete pipe dream while I have the box open I'll look at the amps used and see if I can find any similar types that are rated for higher output but then I'd have to worry about the power supply being able to take it as well as the amplifier board components being able to take the increased current flow.

Oh well,one step at a time.

Welcome! Wow! Great idea's as I have one of these.
How about installing a Sonic T-amp 5086 - I believe is the model number as the main amplifier as it runs off of 12 volts and it puts out a max of 15 watt's into 4 ohm's and this could be modded into this somehow or any bbx that use's 12 volts as it's source of main battery power.
15 watt's would be a good amount of power to have to use in this with the correct crossover and bypassing the main amplifier in this D8443 somewhow. James, more laterz

Hi & welcome.
Plenty of people have customised b-boxes here, & this Philips is a favourite, due to it's looks outstripping it's performance.

a T-amp & speakers of the correct size could make a huge difference.
But as is the nature of all things audio, the amount of improvement depends on lots of variables... good luck & keep us posted!

Yeah that seems like a good idea with the T Amp. I think at first I'll see how the speakers help it and see if I can get some appreciable headroom from better speakers. I know one member here got quite in depth into the 8443 so hopefully he and you all will be able to shed some light on good speaker replacements and such.

Do the speakers come out from the front or the rear? I see screws of some sort at the front of the radio but I'm not sure if those are just decorative covers.

I tried cleaning the heads a bit but I'm still having that runaway treble problem. I'll keep trying to see if I can get the line out to work better but it seems to need an awful lot of drive to work at all.

Best bet is to use an FM transmitter instead of a tape adapter

Yeah,do you know of any good ones? One I had couldn't maintain a good stereo signal and would distort whereas the other one I have doesn't broadcast in stereo.

This thread has some good ones: http://stereo2go.com/eve/forums/a/tpc/f/8306018954/m/9081001055

Thanks Reli,I really appreciate it. The CCrane one looks good and being an amateur radio operator I know that CCrane puts out some pretty good products for the price point. Their solid build quality is something they're known for.

I'm really excited for when I get some new speakers for this because right now I have this thing tuned to my local college radio station and they're playing some electronica and I have to say this thing really cranks! I'm actually kind of surprised by the bass this thing kicks out. Its sitting on the floor about 2 feet away from me on the floor and I can feel the bass kicks reverberating solidly through the floor.

The treble and mids are also really nicely defined and don't start getting out of hand until you start pushing the amps to hard. I'm surprised with the imaging and soundstage this bugger puts out!

Considering the bad rap this guy gets it'll sound legendary when I get some new iron inside of it!

If you push play with no cassette in to play, while your using the line in, it should sound like any other box using line in.

I too had the same quiet result until a member here suggested 'push play.'

Then like magic, actually a strange design in my opinion; it sounded perfect!

Was this pointed out? I dont remember reading this possibly little known fact in this thread yet?

Okay I fixed the problem with the poor sound on the line out/cassette adapter. The MP3 player I was using has a DSP programme that had some features that were making the box unhappy. Mostly it was the whole spatial "3D" deal and preset EQ(I usually EQ dead flat but this player really needs these DSP deals to sound even half good). Its a cheap little MP3 player that I'm using an interim until I can replace my Creative Zen Vision:M.


However a new problem arises,I cannot record to the tape deck. Regardless if I use the line in or line out no actual content will be written onto the tape. I can hear the pop of the record head actuating but no music.

Thanks a lot for the tip,I will give that a shot. I'll eventually have the box apart to replace the speakers and that will be cleaned. Everything else works 100% besides the occasional time the deck won't power up but,again,probably a bad contact point.

Even if the amps weren't rated for much I'm pretty sure the original speakers in there are of much lower sensitivity than newer units on sale today. I'd atleast like to think it could only help...

I've had a fair few Philips b-boxes apart of this vintage. You're in for a shock when you see the size of the speaker magnets...

hey, had a similar idea myself but ran into a wall called life


http://cgi.ebay.com/Galaxy-Audio-S5N-8-Neodymium-Replac...ksid=p3286.m20.l1116


if you need dustcaps i might be able to find some for you.
actually, youd be better off pulling the dustcaps from the orig speakers. the D8443 needs those caps, if you go a little smaller or a little bigger it throws the aestetics of the unit all out of whack.

Though I haven't had it open,the Mag 8300 actually sounds a lot better than the 8443.Both boxes will go very loud but the highs on the 8443 sound rather flat to me.The 8300's graphic equalizer seems to correct the problem.

There are some other problems with the sounds of both of these boxes,not the least of which is it's poor stereo separation.The driver layout is very similar on both boxes.The center woofer probably interferes with the stereo mids and tweets.The bass for most music is actually very good.80s synth pop type music sound really good.Of course the box was produced during that era.However,with music having heavier bass like trance the bass will vibrate like the woofer is being pushed past its design limits.I prefer the looks of the 8443 but the sound of the 8300.

Yeah having that large middle woofer kind of messes with things a bit so you need to keep that "spatial" control maxed or nearly maxed for good stereo separation. I bet a dollar those tweeters are of the piezo persuasion hence the flat highs. I'll hopefully replace those with some nice cone units.

I had the 8443 sitting on top of a chair at a barbeque I attended with friends in front of my friend's apartment and with the volume up about half way it was in danger of drowning out the conversation that was around. I was pretty impressed as when listened to about 3 feet away it has a surprisingly wide sound.

I'm just looking around for good deals on a replacement for the center woofer and the tweeters.