Marantz Car Stereo

[lurp]

About the only thing I love as much as vintage, 70s-era audio is 70s & 80s-era cars, but I haven't found much stereo-wise that a) looks the part, and b) isn't junk. So I've decided I'm just going to build my own

Styled after my beloved Marantz receivers (a 2015 in this case), controlled by a pair of Arduinos, and powered by a 2x50w TPA3116 class-D amplifier, this is a rendering of what the final, single-DIN product will look like:

Marantz Car Stereo - Front

• lurp
• Apr 2, 2023

Behind a piece of smoked plexi-glass, I'll have 3 OLED displays for the VU meters and tuning / mode dial. Finished all the code powering those last weekend, and they look pretty awesome IMO

IMG_20230205_224335_189

• lurp
• Apr 2, 2023

I have a number of small parts to design and 3D print still, but just finished a mock-up faceplate. Once I've verified dimensions and fitment, I'll cut one from AL on my CNC. Still pondering how to to the text though. Vinyl? Silkscreen? TBD...

 

[redk9258]

Looks like a great project!

 

[Lavane]

About the only thing I love as much as vintage, 70s-era audio is 70s & 80s-era cars, but I haven't found much stereo-wise that a) looks the part, and b) isn't junk. So I've decided I'm just going to build my own

Styled after my beloved Marantz receivers (a 2015 in this case), controlled by a pair of Arduinos, and powered by a 2x50w TPA3116 class-D amplifier, this is a rendering of what the final, single-DIN product will look like:

Marantz Car Stereo - Front

• lurp
• Apr 2, 2023

Behind a piece of smoked plexi-glass, I'll have 3 OLED displays for the VU meters and tuning / mode dial. Finished all the code powering those last weekend, and they look pretty awesome IMO

IMG_20230205_224335_189

• lurp
• Apr 2, 2023

I have a number of small parts to design and 3D print still, but just finished a mock-up faceplate. Once I've verified dimensions and fitment, I'll cut one from AL on my CNC. Still pondering how to to the text though. Vinyl? Silkscreen? TBD...

Silk screen with a durable paint.

 

[Lavane]

Will it fit into the standard single DIN dash hole in a vehicle? Cool project.

 

[painttoad]

cool project. hope it turns out better than the turd i owned in the 80s

 

[Lavane]

cool project. hope it turns out better than the turd i owned in the 80s

The 80's and Philips was not kind to Matantz. I remember the cheezy Matantz under dash EQ also.

 

[swechsler]

My one concern would be the small size of the volume and other controls might make one difficult to grab while watching the road.

I look forward to seeing the finished product, though.

 

[spicer]

cool project. hope it turns out better than the turd i owned in the 80s

Stacks and stacks of those went back to the manufacture. To bad too for they promised so much and looked great.

 

[Lou F Quincy]

Cool idea. Will it have a remote USB for a thumb drive? Bluetooth? Fader?
What car is it being designed for?

 

[Lavane]

It should read " Mobile Stereo Console"

 

[lurp]

Thanks for the interest and great ideas!

Silk screen with a durable paint.

Not something I have any experience with. I hope to learn something new with every project, and that's probably what it'll be this time...

Will it fit into the standard single DIN dash hole in a vehicle? Cool project.

Indeed, the faceplate is precisely the dimensions of a single DIN outer bezel. I'm using a frame from the cheapest new CD car stereo I could find ($39!). Why one with a CD? I need the depth for all of the boards I'll be using!

Cool idea. Will it have a remote USB for a thumb drive? Bluetooth? Fader?
What car is it being designed for?

I could certainly include a remote USB, but don't personally find that I ever use them. It'll have bluetooth to connect to my mobile, where I either stream of have much of my music collection on its internal SD card.

No fader in this case, because both cars I envision using one of these in have fader rheostats on the dash or center console (common kit in luxury cars of the era). Specifically, a 1978 Mercedes W116-chassis 300SD and a 1988 BMW E28-chassis M5.

It should read " Mobile Stereo Console"

I like it. I am, however, real estate-limited

 

[lurp]

Since my OP, the mock-up faceplate (dual-color extrusion faltered, so pardon the sharpie) and its support bracket finished printing. I dry fit some of the components I've amassed, and its looking pretty close to what I'd envisioned!

IMG_20230402_205801_526

• lurp
• Apr 2, 2023
• 2

As is often the case with a prototype, I discovered a few things I'd overlooked. Notably:

• My plan to use a horizontal thumb-wheel to the right of the frequency dial for tuning (as would have been period correct) is out the window. The spec sheet for the OLED display I used for the dial gives the bezel dimensions, not PCB dimensions. I should have confirmed that :/ I may still use a wheel oriented vertically with a rotary encoder, or just a momentary on-off-on rocker switch (may the spirit of Saul B forgive me).
  
  
• The body of my 4P3T selector switch is too large, and won't clear the chassis below or the display above. That's going to be a more interesting nut to crack...

IMG_20230402_212554_049

• lurp
• Apr 2, 2023

 

[Lavane]

Very cool so far.

 

[elvi]

"Inboard" the rotary and selector switch. Extend the shaft "back" to the actual part. Float the shaft in a brass threaded tube, two jamnuts to fasten.

( quite common the inboard switches in vintage recievers.. )

That will solve the space issue.

This, and whirlyscope are examples of ability and imagination getting drunk together, and having beautiful babies..

Good on you!

 

[lurp]

"Inboard" the rotary and selector switch. Extend the shaft "back" to the actual part. Float the shaft in a brass threaded tube, two jamnuts to fasten.

I've seen this in practice on a number of receivers and some of my test equipment in fact. That would solve the clearance to the displays above the selector switch, but not below to the chassis unfortunately. I only have ~16mm total diameter to work with, whereas most of the readily available multi-pole selectors (I need 3 poles: two for the L&R audio channels, and one to switch a ground pin to tell the Arduinos what mode we're) are ~25mm.

After a rather exhaustive parts hunt yesterday evening, I believe I've found a suitable (if pricey) option: A Grayhill 51S30-01-3-04N 3-pole, 4-position switch that's only 14.5mm in diameter. $22.89 from Digikey, and I'm off the the races. Until I encounter the next issue, that is

 

[Sansuiman]

Killer project. I'd love something similar in a Sansui theme, if only I had the tools here to do it (the CNC particularly). Well, that and time to play around with designing and building it. I'll look forward to seeing the finished product.

 

[lurp]

Had a chance to do some work on this project over the weekend. Knocked out the CAD drawing for the frame that sits behind the face plate support bracket that will secure everything to the chassis and holds the screens. For what looks like a straightforward bunch of rectangles, it has a lot of detailed geometry and interface points everywhere that took quite a bit of time to measure!

Marantz Car Stereo - Front Frame

• lurp
• Apr 17, 2023

I also received a bunch of various parts and material I've been awaiting, including the aluminum plate, smoked acrylic for the viewing window, and that Grayhill selector (which looks like it'll work perfectly!) I've decided to go with a simple mon-off-mon toggle to the right of the tuning dial screen, which also arrived and looks like it'll work well.

I'm printing what might be the final frame and bracket now from PETG, and will CNC the aluminum and acrylic one night this week. Hoping to have something close to a functional unit by the end of the month...

 

[Lavane]

 

[lurp]

My Fusion is a bit rusty, but I managed to generate a viable toolpath. The faceplate is milling right now out of 1/8in 6061. Fingers crossed that the puny 2mm endmill I'm using doesn't break!

 

[lurp]

Made some progress here and there over the last week, and it's starting to take shape!

Few shots of the front frame installed in the chassis with all 3 OLED screens installed



Designed / printed / installed the component tray in the chassis. From top -> bottom, left -> right: TinySine AudioB bluetooth module (missing, still in transit), Arduino Nano #1 (drives the FM tuner and screen), Wondom 2x50 Class-D amplifier, Arduino Nano #2 (drives the VU meters), Arduino FM tuner module, Tone control board (not installed). Still lots of point-to-point wiring to do



And last but not least, the face plate and its bracket! Took two tries, but I got a decent cut. 6061 Al loves to chatter and 2mm endmills are FRAGILE. You can also see the mon-off-mon switch I went with for tuning up/down. The window is acrylic in 2064 smoked gray, which transmits 27% visible light. I'm worried it's a bit too dark, and have ordered a small sheet of smoked Lexan I30, which lets 47% through. We'll see if that's too clear...



Still lots of finish work to do. The faceplate needs more sanding and silk-screening, need to finish making the selector knob extension on my lathe, lots wiring as mentioned, and am still awaiting several components from AliExpress.

Another couple weeks should see it wrapped up I hope!