Mystery Beovox M70 (Type 6304): Right-aligned drivers

[Martin PV]

Hi everyone,

I recently acquired a pair of Beovox M70s (Type 6304) and started restoring them. I’m a big fan of vintage hi-fi and the engineering behind these classic B&O speakers.

I just finished a full recap of the crossovers, and I have to say, the sound is absolutely fantastic! The bass is tight and balanced, and the vocals and string instruments are incredibly clear and realistic. They are a joy to listen to.

However, I’ve stumbled upon a bit of a mystery with my pair that I hope the experts here can help me solve.

As far as I know, all standard Beovox M70s have their tweeter and mid-range drivers offset to the left side of the front baffle to minimize diffraction. But on my speakers, the drivers are offset to the right.

I have never seen them sold as acoustically mirrored pairs (Left/Right), and every brochure or picture I can find online shows the left-aligned version.

Here are the details of my pair:

• Model: Beovox M70 (Type 6304)
• Serial Number: 1366002
• Driver Date Stamp: The SEAS 25F-EWRX (H131) woofer is ink-stamped “4 21/77”, placing its production in week 21 of 1977. So this was right in the middle of the main production run.
• Crossover Note: Interestingly, the crossover features a factory-fitted 2.2 µF Evox MMK film capacitor on the tweeter circuit instead of the standard bipolar electrolytic (Wico/ROE) usually found in mass-produced M70s.

Does anyone have any information or knowledge about this right-aligned version?

Could this simply be a CNC-routing error / production anomaly at the factory in Struer that slipped through Quality Control, or perhaps a special edition or experiment?

I have attached pictures of the front baffle and the Evox capacitor.

Any insights into the history of this specific production run would be greatly appreciated!

 

Best regards,

Martin

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