Philips D8444 - just a bit of cleaning...for now

So, yesterday I got my first big one. Been dreaming of a bigger one since last summer, when I got my Siemens.

Part 1 - the box
The courier gave me this quite large box

Lets see whats inside...

Oh, its just pieces of newspaper damn.

Oh wait...

Should have seen my face at this moment...

Lets put her on the floor





Sorry for no backside pictures, its like new, only one scrape on the round center piece.

Part 2 - inside of the box

The device had been with a smoker, it smelled quite strong, old tobacco.

There was some dirt inside, seems like it has been opened at some point.

Traces of wiping dust off the bottom. I think the spider chose his place a little badly. He wasn't there no more though.

If it wouldn't have been opened in any point, I can just imagine how much dirt there would have been...


Some random pics

Deck door has jammed at some point, there is some marks on the sides of the door and on the opening mechanism

Motor and date


Part 3 - cleaning

Side connector panel before/after


didn't polish the connectors, just a normal cleaning

Deck

















Speakers
These had some dust on them and the dust covers were dirty. I used microfiber and APC on them.

Left speaker...


...had some spatters on it






Right speaker is now in mint condition








Woofer was very dusty





I used toothbrush for the excess dirt


Then I found out that the shiny "topping" on the surround had lost its shine under the dirt. I took 100% silicone oil and put it on




Dust cap cleaned


Here is the finished woofer


Washed the front cover, also cleaned the deck door and tuner dial window with microfiber and APC (no pics)



[continues..]

i still love these and they are built pretty tough . these sound good and have amazing low bass just not hell of a lot of it .

this s not the loudest box but at average listening it sounds sweet .

the reason the speaker magnets are so small is because the magnets are a stronger magnet material so they really don't need to be that big. if this box put out just a few more watts it would be a monster.


nice job

I know many are saying that the woofer has too small magnet... I take it a grain of salt because it seems back then every speaker had smaller magnets because they were made with higher standards.

I tested the box with a 12V 4A switched-mode power supply, worked really good, voltage stayed at 12.09V even with full blast on cassette.

Awesome looking box!...but I would say that as I've just got one myself! Thanks for all the pics, it's really useful as I haven't opened mine yet. Was it easy to get in to and work on?

Thannk You! Very easy (this being the third one I've opened). 10 screws on the back, just pull the back plate out. The handle should be pointing up or front, otherwise it keeps the upper part of the back plate down. It has lots of space. The wires are detachable for most part and the amplifier board is easy to take out, also the tuner board is easily reachable. Piezos are glued to place and wired to the mids so if you need to remove the mids, I recommend to detach the piezo wires with solder. If you need photos, I can take more of them because my box is still open.

It would be very easy to swap the speakers if one wants. And suitable 13 cm mids/wide range speakers should be easy to come by. The woofer is about 7 - 7 1/2" so it could be more difficult to find alternative.

I think that the woofer is the best bit of this box, it would only need a few watts more. Piezos are pain on the ears and the front is really badly designed. Just a tiny hole and the "horn" is for show only, it has only one narrow straight path.

The mids sound a bit "tight", not really a relaxed sound. Maybe a low pass on the 4k-5k could do some difference.

I have been thinking of giving this box a little mods, since this model is no rarity and when being "as is", its not the greatest.
-Revamp the line-in
-Maybe small good tweeters and make the "horns" to really work (would need time and consideration)
-Good 13 cm speakers that look alike as possible as the originals. On the other hand, if replacing the mids with good wide range speakers, there would be no need for extra tweeters = little less treble, but better sound overall
-A sophisticated tuner dial lighting and...
-Maybe led VU-meters on the tweeter "grilles" I have one VU-unit with 5 or 6 leds per channel, taken from a car EQ (from 80's)

Looks good! At least your tape deck works(hope I didn't jinx it) , mine, D8443 dark, needs the gear replacement. :'-(

I changed my caps to cut some bass frequencies that seem to distort the L&R woofers when at higher volumes. I hear the center speaker reproduce the lows better now that I don't hear the other woofers distorting. With this smaller amp output, I didn't notice a big improvement when I changed speakers, back when I had bought one new. I think this recap gives me a better sound overall, especially at higher volume.

So is there a highpass onboard for the midranges? Can you give me the numbers of those (on the pcb)? Or did you just added caps on the + wires? I've been thinking of changing some of the bigger caps to new higher capacity ones. Also I thought of rewiring some parts, because the wire is so damn thin, 26AWG. Could go with something like 22AWG...

EDIT: So I did some digging and found one store that sells a 4 ohm version of the midrange speakers. The originals are 8 ohms. Bet those have black dust caps but I'll try to purchase two of those, just for a test.

Also I think the woofer amplifier TDA2003 could be changed to TDA2050V. It should work with a single supply and the power should be somewhere around 10 W, compared to 4-5 W of the original.

Things are getting interesting...

I just used 470microFarad 35wvdc caps, on the terminals, at the speakers. You may prefer a different cutoff frequency. Interesting amp choice, would be curious as to its performance, if do able?

I tested my box with only the woofer and it distorts real quickly. When having the mids connected too, the woofers distortion isn't so noticeable, but its there. So the woofer would need a few watts more! I also tried to connect the mids to the woofer channel and it was really weak on 8 ohms. With the woofer disconnected, the sound didn't get distorted so quickly. Will test with woofer connected to a mid/high channel.

Great post! Got 2 of these now, but not in this color. Will clean them in a few weeks and your pics help me out and motivate!! Own one in mint condition and one in lesser condition with a tapedeck isue; when switching between radio and tape there's a little movement in the mechanism (motor) but it doesn't work properly , any idea what that could be?! It's like the switch is not working properly.

I have a service manual of this box, so if anyone is interested just PM/inbox me. Would like the Owner Manual to complete my D8444 dossier

Don't know about any of these modifications.I saw one recently that was turned into an Ipod player.

nice box and good pics of your cleaning...

Good Work L.O....thanx for the info. I've wanted 1 of these for a while. They look well built. Can you tell me if the woofer frames are cast metal or plastic? They look extremely ruggeed. I'm assuming the center woofer is the octagonal edged 1. That octagon basket is stamped for sure but he outer woofers look pretty dope.

great job......the chrome caps are in great shape...thats my favorite part of getting a new box taking it all apart and making look like new

Thank You all! I'll be shooting more pictures as I go forward and clean it some more. For now, I must look in to tuner to get the reception right and stereo working...

Cpl-Chronic said:

Good Work L.O....thanx for the info. I've wanted 1 of these for a while. They look well built. Can you tell me if the woofer frames are cast metal or plastic? They look extremely ruggeed. I'm assuming the center woofer is the octagonal edged 1. That octagon basket is stamped for sure but he outer woofers look pretty dope.

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The midranges are a low cost "light weight" -line with plastic frames and very small magnets. I have one black DUX that has same kind of speakers, just smaller. No bass whatsoever, only "meh" midrange and some highs.

The woofer on the other hand "radiates" quality. There is the AD80800 M4S wide range (dual cone) model, that has got some good talk around the web. This is AD80800 P4S -model, not mentioned anywhere. But it is quality, thats for sure. Only thing I am a bit skeptic about the woofer is its xmax. When I tried the box with only the woofer connected, the sound got compressed/clipping really quickly. But I think its more a low power amp's fault.

The Service Manual (Thanks Hurb!) suggests that it has only 3,2W power at 10% THD for the woofer. I think the woofer could easily handle 10-20W. When the bass knob is cranked, the woofer has a big excursion but the limits are so close that there isn't much oomph when you get farther away from the box. When you sit very close to it, it sounds magnificent.

I tried to order the 4ohm midranges but the reply was they didn't have those or the amplifier chips at all... weird, as their online store suggested otherwise.

Just bagged a second one of these! Already got a minty silver one and now awaiting a dark coloured one like yours which I think is a much better looking colour. Was a bargain BIN on eBay with a very short description and only one picture so I've got my fingers crossed that it's not a pile of junk! you know you've got an obsession when you get two of the same box just because it's a different colour!!

I'm bidding on one of these now. How do they sound?

spaz815 said:

I'm bidding on one of these now. How do they sound?

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Has that auction not ended yet?! both of mine sound awesome!!

Got a new idea for the power boost. I have one left-over amplifier from a Creative 2.1 computer speaker set. The amp works with 12v. I thought about putting this amp board in the box. It should give something around 20 W to woofer and 5-10 W to mids/highs. That should give some bad ass volume increase! I thought I would spare the original amp board and just disable the amp circuits. The amp has a bass level knob and maybe it could be installed in somewhere on the chassis. I would really like to keep the box itself original with minimal modifications... Or, should I just go and make this a killer? Haven't seen it done before... not on this model.

EDIT: OMGOMG!

Decided to do some preliminary testing. I just hooked the speakers on the box up, closed the back with just 2 screws. Running with the amps own 12V ~ 2,9 A power supply. Played some music from my laptop. I thought myself "man, was the bass really so weak, must've been dreaming before". Then I cranked it, WOW! The clarity is 10x the original, and the volume goes hiiiigh! But the bass was lacking, wondered it a few moments.

Then decided to try if the Win 7 own bass boost (+subsonic) would get me more volume or something. Opened the window, and WHAT?! 75 Hz cut-off! Disabled it and plastic almost started to fly! The lows really pound... Hard to say yet, if they fill the room but sitting right next to the machine, it sounds like it goes down to 40Hz or so...

While I'm typing, I tested with test track from Genelec. Last 10 burps were audible. The frequencies in this signal are 16, 18, 20, 22, 26, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 120 and 150Hz. So my guess was right!
Though this was of course tested sitting right next to the box.

The bass level knob on the amp is more a pain because its rated so that the minimum level is already too high. I think I may replace the 50k potentiometer with a 75K(?) or higher value. Should get lower levels and better control.

Pictures may come...

JVC Floyd said:

i still love these and they are built pretty tough . these sound good and have amazing low bass just not hell of a lot of it .

this s not the loudest box but at average listening it sounds sweet .

the reason the speaker magnets are so small is because the magnets are a stronger magnet material so they really don't need to be that big. if this box put out just a few more watts it would be a monster.


nice job

Click to expand...

Will make a monster, thats for sure. What I heard tonight.... man, this will be
Total RMS power will shoot up from about 7 W to around 25+ W. The mid/high section sounds really fresh with more power.