1959 Magnavox Imperial - Danish Modern / Console Upgrade RESTO-MOD (Econowave + 9300 series)

[Almost There]

I picked up this Magnavox Imperial Danish Modern off Craigslist’s from the original owner-family in 2011 and I've tinkered with this restoration on and off over the past decade. The Imperial Maggie has a nice legacy, and I believe I started off with the intention of restoring this to the original. But I kept adjusting the plan as I went along. All in all this resto-mod of an American stereo console classic from 1959 looks great, sounds even better, and is a crowd pleaser. More than a few family and friends have expressed interest and I’ll probably let her go one day soon. It's too nice a piece to be sitting in the basement workshop. But I’ve really enjoyed working on it - and had even more fun listening

 

[Almost There]

Some history on the Magnavox Imperial line from Tube Radio Forum; Apr 29, 2014 :

The top-of-the-line series of Magnavox instruments is the Concert Grand. In 1959, the famous bi-amped chassis appeared. Only two cabinet styles were offered, French Provincial and Danish Modern, the latter featuring twin, reverse-grained glass lids. These instruments cost nearly the price of a new Chevrolet in 1961, starting at almost $1000.

The Imperial series is a step below the Concert Grand instruments. There are two distinctly different series of Imperial instruments. The "big" Imperials are housed in smaller versions of the Concert Grand cabinet, commonly 56" or 60" in length, 32" tall and 19" wide. These instruments utilized a bi-amp chassis ala the Concert Grand with two 5U4 rectifiers, 3 12AX7 pre-amp/phase inverter tubes, and 6 6V6 audio output tubes. P-P 6V6's for the 15" speakers and single ended 6V6 for the horns.

A common way to distinguish an Imperial from a Concert Grand, especially in photos, is by the placement of the horns. MOST Imperial models have the horns above the speakers. MOST Concert Grand models have the horns to the side of the speakers. The Imperial series appears to have been built in greater numbers than the Concert Grand. The Imperials use the same tuner as the Concert Grand, with tuning eye, and the same turntable as the Concert Grands. The Danish Modern cabinet style has proven more elusive than French or Italian Provincial.

----------
This video of the 1959 Magnavox sales brochure on Youtube features the Danish Imperial as its cover girl:

.

ORIGINAL photos:

 

[Almost There]

THE WORK:

The console cabinet was in excellent condition and very well made, solid walnut. However, one of the faux-wood glass sliding cover panels was cracked and after I got into the guts of the cabinet, including the speaker sound boards, I decided to eliminate the sliding glass panel system, and replace it with a solid, flip top top. I then re-surfaced the top and the speaker sound boards with some bird’s-eye maple veneer I had left over from another project. The bird's-eye looks great against the walnut, and shined after a shellacking.

I preserved the original speaker fabric and made up some new magnetic grilles to replicate the look of the original (with the grilles on and the sliding front access panel in place). See photos with grilles, post #1. So I made some attempt to keep the original Magnavox look as an option.

 

[Almost There]

Speakers: Speakers were always touted as a Magnavox strong point. Each channel on the Imperial uses a heavy-duty 15" bass speakers with 24 oz. magnets, along with a 1000 cycle exponential treble horn.

From hammr7, AK Subscriber, Oct 23, 2008) “ID on Vintage Magnavox Speakers?”​

Many of the older Magnavox speakers, at least the Alnico ones, seem to be similar to older Jensens. In fact, many of Jensen's late 50's triumphs in supplying speakers for organs, guitar amps, and the like came at the expense of Magnavox. The Jensen speakers were originally built to match Magnavox specifications.​

When I broke down the speaker assemblies I found that one of the treble horns was blown and the other sounded very tinny. The 15" drivers however were in excellent condition and it became immediately evident that I needed to save these.

I had purchased components for a Zilch Econowave upgrade and decided to go that route, with the original Magnavox 15" alnico as the anchor.

 

[Almost There]

The original Magnavox amplifier in this Imperial was the 182BA:

“Magnavox 182 BA” at https://audiokarma.org/forums/index.php?threads/magnavox-182-ba.502726/ (kward, AK Subscriber Feb 18, 2013): "This is a strange beast - bi amped treble and bass for each channel on a stereo chassis, and the treble amps are single ended!!... there's a couple of things to consider… Nice little amp if you can work out the little quirks."​

There's lots of posts here on AK regarding the 182 BA. I decided not to try and tackle the bi-amped crossover and instead have substituted in a 9300 series amp from another Magnavox console. For the 9300, I followed dcgillespie very popular & highly recommended post: https://audiokarma.org/forums/index.php?threads/more-fun-with-magnavox-the-9300-series.687735/

1. Installed a power switch in place of the Molex plug​

2. Installed a fuse, 2a fast blow​

3. Replaced the coupling capacitors with .1uf and then the smaller ones with .01uf.​

4. Kept original cap can on top for looks (it is better than there being a hole)​

5. Replaced four power capacitors:​

a. 40uf@450volts​

b. 30uf@450 volts​

c. 10uf@450 volts​

d. 20uf @ 25 volts.​

6. Bypassed the balance pot; replace it with a pair of 360-ohm resistors.​

7. Installed banana plugs for the back of the amp.​

8. Installed a new pilot light.​

9. Installed a new volume pot.​

xx. (Output transformer upgrade (e.g. Edcor) would be the probable next step.)​

 

[Dswankey]

I like what you've done with it!!!!!

How does it sound?

 

[Almost There]

It sounds great !!!. I don't have any professional measuring equipment, but to my ears it is very enjoyable listening. Very tubey and warm. The bass is deep, but not punchy. It gets better as it warms up. And the 9300 series amp has plenty of driving power. It's very nice, and a fun experience.

 

[Lavane]

Very nice! The Maple makes it really pop.

 

[gadget73]

The 182 is the stereo bi-amp one right? I have one of the mono bi-amps from the slightly older model. Push-pull-parallel 6V6 on the bottom end, single end 6v6 for the treble amp. Even more of a mismatch power-wise but it seems to work. I have it stuck in a aux cabinet from a Magnavox with the original 15" and horn, surprisingly it balances out better than you'd expect considering one amp is nearly 8x the power of the other.


console looks great. I do love that base / foot style.

 

[Almost There]

Yep, 182 is bi-amped stereo. Very specialized, and limited IMO by the integrated crossover. Instead of trying to by-pass the crossover, I went for something more straightforward and simple with the 9304.

At the end of the day, really all I've built is a standalone speaker cabinet that can be hooked up to any power amp. The updated/modified 9304 is working out just fine however and it keeps it all in the Maggie family.

The original Collaro turntable and the 54-03-10 tuner/pre-amp are still in place and untouched (including the Magic tuning eye). I don’t think I’ll ever tackle these, but the option is there in case anyone down the road wants to bring them back up. In the meantime, I’m using a iFi nano iOne bluetooth DAC as the source component which is convenient (especially for guest listeners) and gives this vintage console an up to date hi-fi feel. (https://ifi-audio.com/products/nano-ione/)

 

[gadget73]

I did some hammering on the stock crossover. Kept the basic design, just made some alterations to make it stop overlapping terribly in the middle and extend the bottom end. Sounds a lot cleaner, but its not as loud without that huge midrange overlap. If you want to seriously alter the crossover points its kind of inconvenient. They use a passive LC crossover setup, so at some point you have to change the inductors if you want to move things around too much.

wouldn't mind a twin, and a decent set of 2 way that happen to want a crossover at the stock point.

Surprised it has a Garrard. Magnavox usually shipped with a Collaro.

 

[Almost There]

oops, my typo - turntable is original Collaro (not garrard)

 

[tonyk]

Very nice!

 

[macyjrm]

A most excellent project built to high standards. Thanks for sharing your modern interpretation of that classic Maggie.

 

[Lavane]

Yep, 182 is bi-amped stereo. Very specialized, and limited IMO by the integrated crossover. Instead of trying to by-pass the crossover, I went for something more straightforward and simple with the 9304.

At the end of the day, really all I've built is a standalone speaker cabinet that can be hooked up to any power amp. The updated/modified 9304 is working out just fine however and it keeps it all in the Maggie family.

The original Collaro turntable and the 54-03-10 tuner/pre-amp are still in place and untouched (including the Magic tuning eye). I don’t think I’ll ever tackle these, but the option is there in case anyone down the road wants to bring them back up. In the meantime, I’m using a iFi nano iOne bluetooth DAC as the source component which is convenient and gives this vintage console an up to date hi-fi feel. (https://ifi-audio.com/products/nano-ione/)

View attachment 2419684

You could connect the Bluetooth to the aux input on the tuner/preamp and have a FM tuner and tone controls also.

 

[Dadbar]

Really nice job. Some of those old Magnavox consoles were really cool.

 

[x-rayrad]

Looking for help on a 1958 Magnavox 300H CG. Trying to find out what's original and what isn't. Both amps are 150DB's, which have the 4 - 6V6's and 1- 6V6. Tuner markings are 57 01 11 and
R054-03-10. Horns are 580051's. Woofers are 584037 & 583982. Reading past postings, I'm wondering if this has any original parts. Any help would be appreciated.

 

[FlaCharlie]

Looking for help on a 1958 Magnavox 300H CG. Trying to find out what's original and what isn't. Both amps are 150DB's, which have the 4 - 6V6's and 1- 6V6. Tuner markings are 57 01 11 and
R054-03-10. Horns are 580051's. Woofers are 584037 & 583982. Reading past postings, I'm wondering if this has any original parts. Any help would be appreciated.

I'd suggest that you ask the moderators to create a new thread for you since this one is really about one particular "resto-mod" of a similar console and not a more general discussion. You can do that by clicking on 'Report' at the bottom left and making a request for a new thread. You'll likely get more attention and help by doing so.

In the meantime, here's the Sams for the amp. It's in pdf, which can be enlarged to show detail. I'm afraid I can't help you with the rest but if you include the console model number in the title of a new thread I'm sure there are others here who can provide details and can tell you if what you have is original or not.

 

[raycarr00]

amazing design! I'm impressed. have a '64 rca/ victor console n love the tube sound. able to plug a variety of pre amps to the amp for sound variety.