1 2
DrBoost
DrBoost MegaDork
7/4/17 1:13 p.m.

So, I've been wanting to tackle a project like this for some time because I like the look and build quality of older furniture, but being an audiophile I want newer tech and top-notch sound quality.
Enter Project Boosted Tunes
I was at Goodwill and found a console stereo, nope, radio since this was a mono speaker and only had AM, Weather, and Police bands. Here's the beastie as dragged home

testing to see if the picture shows......

Bibs
Bibs New Reader
7/4/17 1:18 p.m.

Awesome. If I had the right house for antiques, I would do something similar. A friend of mine gutted a 60's era MCMC stereo cabinet. He put a 12v power supply in, and used one of the "hidden" car stereo units used in old muscle cars. It's all controlled through his phone, and sounds great!

DrBoost
DrBoost MegaDork
7/4/17 1:28 p.m.

Ok, so the picture shows. Hot dog! I'm using imgur for the first time since Photobucket is the suck.
So, when I got it the power cord was deteriorated and would no doubt burn my house down. There was even a sticker next to the price tag that said "Do not plug in. needs new cord"
Here's a few more pics of it when I got it home.

Here's the worst of it. You can see cracking in the veneer and a small gouge from something being dropped against the side of it. I suspect that gouge happened at Goodwill since it was very fresh, and they are not careful about handling anything.

Here's the back of the cabinet. No cover panel, and no evidence of there ever being one either. Notice the record storage compartments on each side. They are made from cardboard!! And they are original to the radio. I'm shocked that something built 71 years ago, something that uses tongue and groove and dovetail joinery used cardboard!
I will be building new storage out of plywood during the process.
The record player is in a drawer that pulls out.

I can't imagine trying to thread a record in there, there's not much extra height, and the drawer only pulls out 2/3 of the way. The record player appears that it would function, the cords are there, and by spinning the platter by hand I can see the mechanisms moving around, the tone-arm travels up and down and left-right. I'll sell the turntable to recoup the purchase price!
Hot dog! I'm gonna grassroots this thing!!!
Here's the lid to the tuner, I can't believe the lid is there since it's not even attached!

Speaking of tuners, here it is in all it's nasty glory. I hope I can get that looking decent.

I had a hard time even seeing a brand through all the grime. It's a Sparton.

The cabinet was in really good shape.

noddaz
noddaz SuperDork
7/4/17 2:07 p.m.

Classic looks with modern electronics. Sounds like a great idea to me.

wheelsmithy
wheelsmithy Dork
7/4/17 2:12 p.m.

Excellent Project! Here's mine. Yes, it is dusty, but not as bad as the pictures show.

Viewing intently.

RossD
RossD UltimaDork
7/4/17 2:28 p.m.

Nice! Do your modern electronics involve tubes?

Jerry From LA
Jerry From LA SuperDork
7/4/17 2:29 p.m.

Is everything there? No reason not to use the old tube guts because it would be very cool. I would recommend hooking the unit up to a variac (after replacing the power cord), turning the machine on, and starting with 10 volts. Feed another 10 volts in every hour or so. This will help re-form the capacitors after sitting for a long time. I built a variac out of an old commercial-grade auditorium dimmer pack from the '70s. The whole thing cost me less than 30 bucks to build, 25 of which was the dimmer.

The big reason to re-use the old guts is the phono preamp. It may not use the RIAA curve that did not become standard until after this unit was built, especially if it's a 78-rpm-only unit. So substituting modern stuff might sound weird.

DrBoost
DrBoost MegaDork
7/4/17 3:32 p.m.
RossD wrote: Nice! Do your modern electronics involve tubes?

Not yet, but one day I suspect it will. You know I've been wanting to build a tube amp for some time, and this just begs for tubes.

DrBoost
DrBoost MegaDork
7/4/17 3:33 p.m.
Jerry From LA wrote: Is everything there? No reason not to use the old tube guts because it would be very cool. I would recommend hooking the unit up to a variac (after replacing the power cord), turning the machine on, and starting with 10 volts. Feed another 10 volts in every hour or so. This will help re-form the capacitors after sitting for a long time. I built a variac out of an old commercial-grade auditorium dimmer pack from the '70s. The whole thing cost me less than 30 bucks to build, 25 of which was the dimmer. The big reason to re-use the old guts is the phono preamp. It may not use the RIAA curve that did not become standard until after this unit was built, especially if it's a 78-rpm-only unit. So substituting modern stuff might sound weird.

Everything is there, minus a tube or two.
I don't plan on using anything but the cabinet. I'll put a small amplifier and a bluetooth board in there, and put modern speakers where there used to be a single 10"? driver. I don't even own a record anymore, so I'll just sell it off to zero out the purchase.

DrBoost
DrBoost MegaDork
7/4/17 3:34 p.m.
wheelsmithy wrote: Excellent Project! Here's mine. Yes, it is dusty, but not as bad as the pictures show. Viewing intently.

Me likey!

Jerry From LA
Jerry From LA SuperDork
7/4/17 3:48 p.m.

I promise this will be my last shot....Ironically, the tube electronics are usually good as designed. It's the mechanical bits on these old units that were the weak links. Turntables and speakers were where the large advances in sound quality lay. You can still hook up anything you want like bluetooth or whatever. Someone might still make a good quality coaxial driver for your speaker setup. Tannoy used to make two-and-three-way speaker setups, the likes of which will simplify your system and surprise you with the sound due to improved phase coherence.

stuart in mn
stuart in mn UltimaDork
7/4/17 6:49 p.m.

Before trying to use the original electronics they'd need to be rebuilt - no doubt all the capacitors have gone bad and need to be replaced, for one thing. It will also be a mono amplifier, so no stereo sounds will be available. Not saying it's a bad idea as I like the sound old tube radios, but it's not gonna be plug and play by any means.

edited to add: Dr. Boost, what brand is that thing? It look pretty similar to a Bendix console I had a long time ago.

Jerry From LA
Jerry From LA SuperDork
7/4/17 7:25 p.m.
stuart in mn wrote: Before trying to use the original electronics they'd need to be rebuilt - no doubt all the capacitors have gone bad and need to be replaced, for one thing. It will also be a mono amplifier, so no stereo sounds will be available. Not saying it's a bad idea as I like the sound old tube radios, but it's not gonna be plug and play by any means. edited to add: Dr. Boost, what brand is that thing? It look pretty similar to a Bendix console I had a long time ago.

Read my post regarding using the variac to re-form caps. It works unless there's been a catastrophic failure, usually in the power supply. That would result in an incredibly loud 60-cycle hum.

Also, I may be wrong but this will end up being a monophonic setup. Matching some kind of speaker system to that cabinet would be next to impossible and not necessarily desirable, since the system was either open or cardboard-backed. The only way to do stereo would be abandoning the original speaker placement and just using the piece as a hi-fi cabinet for the electronics.

It could be a cool mono piece and a coaxial-type driver works well in that realm.

DrBoost
DrBoost MegaDork
7/4/17 9:13 p.m.

In reply to Jerry from LA and Stuart in MN (both guys put their location in their screen names, cool huh):
I'm not going to use any of the electronics at all. I would like to refurb the internals just because it'd be cool, but I have to watch scope creep. I know what time I have available and what my current abilities are. If I decide to get into antique electronics this will never get done.
Someone before me, from the looks of it, decades ago removed the speaker and replaced it with a solid wood panel covered with upholstery cloth.
I'm going to leave the tuner in for looks, assuming I can make it look decent, and install modern electronics and modern speakers in cabinets that are built into the chassis. When I'm done it'll be stereo with a subwoofer, 2.1 channels.
When I decide to enter the world of tube amps, I'm going to build my own amp. I very well may do that for this down the road.

stuart in mn
stuart in mn UltimaDork
7/4/17 10:01 p.m.

I've heard of the variac re-forming method, but while it may work on electrolytic capacitors from the 1960s I'm not so sure it would be effective on those old paper and wax capacitors from the 1940s. Once they start to leak they're pretty much done for. Full disclosure...I am an electrical engineer but I haven't worked on small format eletronics (tube or transistor) for many years now, so I won't claim to be an expert.

DrBoost
DrBoost MegaDork
7/4/17 10:06 p.m.
stuart in mn wrote: edited to add: Dr. Boost, what brand is that thing? It look pretty similar to a Bendix console I had a long time ago.

It's a Sparton Model 7-46 nearest I can tell.

DrBoost
DrBoost MegaDork
7/5/17 9:58 a.m.

Let the cleaning commence!!
I chose this cabinet because it's in good shape. I don't need to sand it down and refinish it, just clean it and maybe fill that small gouge. So, lets get the compressed air, shop-vac, Windex, and Murphy's Oil Soap out and get dirty...to get clean?

Here's the turn table drawer pulled out and simply wiped off, no soap used yet! It looks great!
Look at that mahogany glimmer! In person, it looks just amazing.

The tuner turned out real nice. There's two pieces of glass, one at the cabinet and one on the tuner. The glass on the tuner has the script painted on it. For some reason, that piece of glass was 1,239 times dirtier than the top piece of glass, the one that you can actually tough. Weird. Anyway, Windex, microfiber cloths, newspaper, and q-tips and some child-labor later and we have a result!!

Before:

And after:

onemanarmy
onemanarmy New Reader
7/5/17 10:33 a.m.

awesome. looking forward to more.

DrBoost
DrBoost MegaDork
7/5/17 10:54 a.m.

Ok, here's that rear shot of the radio I posted earlier.
In the upper left corner is the tuner/amplifier. Upper right is the turn table. Center on the bottom is the antenna, and behind that is the baffle board that isn't actually a baffle since there's no driver mounted on it. Somebody cut the wires, removed the driver and put a hunk of plywood in it's place, covered in upholstery fabric.
Again, there are two record storage bins that are made of cardboard.

With all the components out, it was high time to remove the cardboard to take measurements and reconstruct them from plywood.
Here's the cabinet in all its naked glory.

DrBoost
DrBoost MegaDork
7/5/17 10:59 a.m.

Here's the 'chassis' with the storage boxes built. I used 1/8" birch plywood and 1X1 in the corners for reinforcements, and under to make a place to more securely mount the boxes.

stuart in mn
stuart in mn UltimaDork
7/5/17 12:46 p.m.

Progress!

There are places out there that sell speaker cloth in vintage patterns - I haven't saved any links so you'd have to search for them, but you could probably find some cloth that's more appropriate for the front grille. They have it both for old radios, as well as guitar amps.

Wall-e
Wall-e MegaDork
7/5/17 12:57 p.m.

In reply to stuart in mn:

I picked up some vintage speaker cloth from eBay. At some point I want to build a small old looking speaker for her iPod to go with her other 1950s-60s era office stuff.

DrBoost
DrBoost MegaDork
7/5/17 1:18 p.m.

So, for the speakers. Originally I was going to use a 6.5" driver and dome tweeter salvaged out of an Advent tower speaker I got from goodwill just for this project. Well, in true GRM fashion, I upgraded the thing before I even started! I have some truly amazing Celestion studio monitors at home that are currently doing nothing since building my Magnepan 5.1 setup in the theater (build thread)
So I decided to use the Celestions, they are full-range and I run them without a crossover of filter of any kind. The Celestions are already in boxes, so I'll just attach the boxes to the baffle board after cutting the appropriate holes (there are currently no holes for speakers in the board.)
I have a Rockford Fosgate 8" I plan on using for the subwoofer. I should be able to fit everything in there.

.....at least that was the plan. I didn't want to screw the Celestion boxes to the baffle from the front of the baffle because I want the speakers to be serviceable without cutting the fabric. So, I decided to just cut almost the whole baffle away, leaving 2" around the perimeter, and 2" in the middle for some rigidity. Then I built a shelf in the bottom of the radio. Then I'll simply stack the boxes on the shelf with the sub behind them.
Here's the baffle all cut away getting ready for grill cloth. I found some reproduction cloth at www.richmonddesigns.com. Stay tuned for pics....

DrBoost
DrBoost MegaDork
7/5/17 1:31 p.m.

That brings us to the subwoofer. I used the RF 8" because that's what I had laying around. This radio isn't going to be used for critical listening so I'm not terribly concerned with ultimate quality, just want good sounding background music and the occasional ability to pump up the jams as the kids say (or at least, used to). Judging from simimilar speakers I've owned from Celestions, the Celestions I'm using are 90 or 92 Db sensitivity drivers, so the modest amp will be sufficient.
So I placed the boxes in the cabinet on the shelf I built and measured the space I have to work with. Uh oh. Not enough for the sub. I'd have to either lose one of the side storage boxes (don't want to do that), lose the drawer that the record player was in (don't want to do that I have plans for that space), or have the sub sticking a few inches proud of the rear of the cabinet, forcing the cabinet to be placed a few more inches away from the wall. Don't want to do that. So, for now I'm going to forgo the sub to keep the project moving.
The Celestion drivers I have don't have any model identification info at all, meaning I had no specifications to use when building the enclosures. As a result, when I built the boxes they are in I guesstimated the volume I needed. Well, this will prompt me to contact Celestion and get the proper T/S specs and build a proper box. I'll build them shallow to free up precious inches for a sealed enclosure for the sub.
Onward and upward!!

DrBoost
DrBoost MegaDork
7/6/17 7:00 a.m.

Well, it's (mostly) done. I'll get some pics of the inside of the cabinet in a bit, maybe during lunch today.
I got some reproduction grill cloth that looked great on the computer screen, looked good in person, and pretty good on the cabinet Basically, it looked very yellow on the screen, we thought that would look great against mahogany. When it arrived it was more orange. A little disappointed, but not a big deal. When I put it on the cabinet, from 6' away, it looks almost a little brown, and you lose the detail in the pattern. Not a big deal really, it still looks good.

Here's the finished product

And the former turntable drawer is where my 3D printed charging station now resides. Kinda nice, all the cords are hidden, the devices are out of site, and the irony of a 71-year old radio housing modern tech:

1 2
Our Preferred Partners
LKBwPUvM7kWa49xhUr7MlX0JT425CrxYDRzUoxtleUIsBCFYrC5t56DDhHmrYEtm