Repairing vintage speakers

bic venturi speakers

Trash or treasure – are old, broken speakers worth fixing?

It seems that the British Industries Corporation (BIC – actually an American company cashing in on the popularity of British Hi-Fi gear at the time) sold a lot of their Formula 2 speakers around my local area back in 1974. That’s the only way I can explain a peculiar coincidence.

The Local Council has a biannual junk collection service for residents and occasionally interesting items of questionable value are placed kerbside. In the early 1990’s my friend Jason, a talented musician and sound engineer, found a pair of these speakers on the roadside.¬† He tried them out but it seemed some of the drivers had blown. On the back however, he found a set of fuses, one for each woofer, horn mid range and tweeter and upon replacing the defective ones they sounded pretty good. I remember visiting soon after and being impressed by such a lucky find. Although missing the grills, the vinyl wrapped cabinets were in very good condition. I had never heard of the BIC Venturi brand name but a quick listen impressed me even further and I remember being somewhat envious at the time. Jason still has these speakers, although his young toddler managed to push in the dustcaps on the tweeters and woofers.

weathered bic venturi speakers
Weathered Bic Venturi Speakers

Fast forward to around 2008 when another good friend Clive, also involved in the audio industry and also friend of Jason’s, found a pair of BIC Venturi Formula 2’s on the roadside. What are the odds? Again an easy fuse replacement restored these back to full working condition. He was building a house on a budget at the time and created a recess in a living room wall where he placed these speakers behind a sonically transparent screen. This pair didn’t look as pretty as Jason’s but he still has them today and they still work.

Budget speakers for the shed

Recently, I had been setting up my workshop and needed some cheap lighting, so I found a guy selling half a dozen fluorescent lights on an online marketplace. I arranged to meet him at his house but before I left I checked out what else he was selling online. He had a pair of scrappy looking BIC Venturi Formula 2’s for sale for $10 (US $7.50)! They had definitely seen better days but I thought that they would be great to use in the workshop. He was a DJ and had a couple of turntables set up in his living room next to the speakers. He told me they worked OK and when I told him the story of Jason and Clive’s finds he sheepishly admitted that he too had found them on the roadside. I took them without testing or haggling the price – a pair of working speakers for ten bucks is a pretty rare find in Australia.

First test, blown fuses

Once I got them home I noticed that the particleboard cabinets were in pretty bad shape, the mitered corner joints were coming apart in a couple of places and there were cobwebs and what looked like spider eggs in the ports. I brushed them out a bit and made a mental note to fumigate these. I set them on the kitchen bench and hooked them up to a vintage NAD 3020 amplifier from 1978, nominally a 20 Watt per channel amp but capable of brief forays over 50 Watts at 8 Ohms or more than 70W transients at 4 Ohms. The Formula 2’s are rated 75W at 6 Ohms so I figured this amp was a good match and originating from the same era, would sonically transport me back in time. I didn’t want to start dissecting my home theatre setup for a source component so I connected an APTX Bluetooth receiver and streamed some music from Spotify Premium (I can see the audiophiles cringing right now). The speakers sounded awful, only one tweeter on the left channel and the woofer on the right was working – technically the guy was right, they were working… sort of. I turned these around to locate the fuses on the back, still covered by their plastic covers which normally would have been lost.

Bic Venturi back panel
BIC Venturi speaker connections and fuse panel on rear

I tested all 6 fuses and sure enough 4 were blown. People must just throw these speakers out not realizing that they have fuses, or only do a visual check of the fuses. The 3AG fuses have a very fine wire that is thinner than a human hair and even when blown, sometimes most of the wire may still be visible and appear intact. You really need to use a multimeter and you must remove the fuse from its holder. Obviously if you check the continuity of the circuit across the fuse terminals while they are in place, it may just be indicating an intact a continuous circuit through the voice coil of a functional driver. And this is the beauty of fuse protected speakers like this, it is virtually impossible to blow the speakers unless you have put in a fuse that is rated higher than it should be then crank up the amp too high or force a weaker amp into clipping. Fuse protection is not that common and was generally the domain of higher end speakers. Formula 2 fuse values are printed next to the fuses; woofers require 3AG 2A / 250V , midrange 3AG 0.5A / 250V and tweeter 3AG 0.375A / 250V. I rummaged around my fuse collection and found suitable replacements, although the closest value for the tweeter I had was 0.365A. Choosing a slightly lower value than specified is always safer than a higher value, of course.

Listening first impressions

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Sed ut iaculis ligula, ac pulvinar urna. Aliquam ultrices ante leo, id malesuada orci dignissim elementum. Sed aliquam congue enim a facilisis. Nulla venenatis mauris id dolor facilisis, quis accumsan tortor porta. Pellentesque facilisis ligula est, ut commodo sapien interdum eu. Suspendisse nec lectus ac magna suscipit aliquam vel in odio. Aenean et cursus eros, tincidunt rhoncus nibh. Phasellus consectetur, enim sit amet molestie vestibulum, diam dolor vehicula eros, a consequat tellus diam non metus.

Morbi ligula enim, laoreet et quam vitae, mattis blandit mi. Praesent faucibus nibh arcu, ac condimentum mi posuere in.

Broken Speakers

BIC Venturi - Formula 1Lorem ipsum dolor sit amet, consectetur adipiscing elit. BIC Venturi Proin at mollis lectus. Integer et dolor tempus, convallis dolor quis, rhoncus ligula. Suspendisse pulvinar arcu odio, quis pellentesque nunc elementum in. Donec aliquam convallis efficitur. Donec odio tortor, scelerisque nec rhoncus vel, suscipit non mauris. Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Nunc imperdiet odio vel luctus suscipit. Vestibulum imperdiet vulputate leo, eu efficitur arcu mollis nec.

Sed ut iaculis ligula, ac pulvinar urna. Aliquam ultrices ante leo, id malesuada orci dignissim elementum. Sed aliquam congue enim a facilisis.

Balance control

Speaker balance control
Speaker balance control – front

Nulla venenatis mauris id dolor facilisis, quis accumsan tortor porta. Pellentesque facilisis ligula est, ut commodo sapien interdum eu. Suspendisse nec lectus ac magna suscipit aliquam vel in odio. Aenean et cursus eros, tincidunt rhoncus nibh. Phasellus consectetur, enim sit amet molestie vestibulum, diam dolor vehicula eros, a consequat tellus diam non metus.

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed ac volutpat turpis, et lacinia est. Fusce pulvinar, felis non consectetur interdum, elit nulla laoreet turpis, id mollis lacus nulla vel elit. Phasellus vitae mauris eros. In bibendum sollicitudin nisl. Donec placerat magna vitae elit interdum ornare. Mauris ullamcorper justo ligula, consequat posuere nunc ultrices ut.

Curabitur maximus tristique gravida. Vestibulum bibendum sagittis arcu finibus mattis. Proin at dui quis libero sagittis iaculis. Mauris ultricies eget lacus in volutpat. Praesent massa quam, varius ac sagittis sit amet, aliquam a turpis. Curabitur eu dolor lobortis, vulputate erat quis, semper tellus. Nam pellentesque tincidunt suscipit. Pellentesque molestie luctus urna. Phasellus ut vestibulum lectus. Sed tincidunt nibh ut tortor cursus, et finibus ante porta. Suspendisse condimentum arcu nec magna commodo aliquam. Sed mi diam, aliquet eget metus eu, iaculis sodales lorem. Curabitur vulputate accumsan dolor et maximus. Phasellus et cursus dolor. Phasellus feugiat ante est, pellentesque viverra urna dignissim ac.

Morbi ligula enim, laoreet et quam vitae, mattis blandit mi. Praesent faucibus nibh arcu, ac condimentum mi posuere in. Sed malesuada ac sem nec rutrum. Etiam condimentum lorem eget tincidunt rutrum. Aenean a ex velit. Pellentesque scelerisque enim sit amet efficitur cursus. Nam sed consequat nisl. Fusce interdum risus id facilisis fermentum. Etiam sit amet euismod lectus, quis efficitur enim. Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vivamus pretium sollicitudin aliquam. Aenean enim nibh, luctus sit amet ullamcorper sed, volutpat efficitur felis. Vivamus faucibus est vitae pulvinar luctus. Sed ut diam mi. Integer turpis augue, dictum vitae quam eget, tempor tincidunt purus.

Fixing BIC Venturi Speakers

Changing Fuse

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin at mollis lectus. Integer et dolor tempus, convallis dolor quis, rhoncus ligula. Suspendisse pulvinar arcu odio, quis pellentesque nunc elementum in. Donec aliquam convallis efficitur. Donec odio tortor, scelerisque nec rhoncus vel, suscipit non mauris. Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Nunc imperdiet odio vel luctus suscipit. Vestibulum imperdiet vulputate leo, eu efficitur arcu mollis nec.

Sed ut iaculis ligula, ac pulvinar urna. Aliquam ultrices ante leo, id malesuada orci dignissim elementum. Sed aliquam congue enim a facilisis. Nulla venenatis mauris id dolor facilisis, quis accumsan tortor porta. Pellentesque facilisis ligula est, ut commodo sapien interdum BIC Venturi eu. Suspendisse nec lectus ac magna suscipit aliquam vel in odio. Aenean et cursus eros, tincidunt rhoncus nibh. Phasellus consectetur, enim sit amet molestie vestibulum, diam dolor vehicula eros, a consequat tellus diam non metus.

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed ac volutpat turpis, et lacinia est. Fusce pulvinar, felis non consectetur interdum, elit nulla laoreet turpis, id mollis lacus nulla vel elit. Phasellus vitae mauris eros. In bibendum sollicitudin nisl. Donec placerat magna vitae elit interdum ornare. Mauris ullamcorper justo ligula, consequat posuere nunc ultrices ut.

Curabitur maximus tristique gravida. Vestibulum bibendum sagittis arcu finibus mattis. Proin at dui quis libero sagittis iaculis. Mauris ultricies eget lacus in volutpat. Praesent massa quam, varius ac sagittis sit amet, aliquam a turpis. Curabitur eu dolor lobortis, vulputate erat quis, semper tellus. Nam pellentesque tincidunt suscipit. Pellentesque molestie luctus urna. Phasellus ut vestibulum lectus. Sed tincidunt nibh ut tortor cursus, et finibus ante porta. Suspendisse condimentum arcu nec magna commodo aliquam. Sed mi diam, aliquet eget metus eu, iaculis sodales lorem. Curabitur vulputate accumsan dolor et maximus. Phasellus et cursus dolor. Phasellus feugiat ante est, pellentesque viverra urna dignissim ac.

Morbi ligula enim, laoreet et quam vitae, mattis blandit mi. Praesent faucibus nibh arcu, ac condimentum mi posuere in. Sed malesuada ac sem nec rutrum. Etiam condimentum lorem eget tincidunt rutrum. Aenean a ex velit. Pellentesque scelerisque enim sit amet efficitur cursus. Nam sed consequat nisl. Fusce interdum risus id facilisis fermentum. Etiam sit amet euismod lectus, quis efficitur enim. Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vivamus pretium sollicitudin aliquam. Aenean enim nibh, luctus sit amet ullamcorper sed, volutpat efficitur felis. Vivamus faucibus est vitae pulvinar luctus. Sed ut diam mi. Integer turpis augue, dictum vitae quam eget, tempor tincidunt purus.

Upgrading Capacitors

Placement of BIC Venturis

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin at mollis lectus. Integer et dolor tempus, convallis dolor quis, rhoncus ligula. Suspendisse pulvinar arcu odio, quis pellentesque nunc elementum in. Donec aliquam convallis efficitur. Donec odio tortor, scelerisque nec rhoncus vel, suscipit non mauris. Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Nunc imperdiet odio vel luctus suscipit. Vestibulum imperdiet vulputate leo, eu efficitur arcu mollis nec.

Sed ut iaculis ligula, ac pulvinar urna. Aliquam ultrices ante leo, id malesuada orci dignissim elementum. Sed aliquam congue enim a facilisis. Nulla venenatis mauris id dolor facilisis, quis accumsan tortor porta. Pellentesque facilisis ligula est, ut commodo sapien interdum eu. Suspendisse nec lectus ac magna suscipit aliquam vel in odio. Aenean et cursus eros, tincidunt rhoncus nibh. Phasellus consectetur, enim sit amet molestie vestibulum, diam dolor vehicula eros, a consequat tellus diam non metus.

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed ac volutpat turpis, et lacinia est. Fusce pulvinar, felis non consectetur interdum, elit nulla laoreet turpis, id mollis lacus nulla vel elit. Phasellus vitae mauris eros. In bibendum sollicitudin nisl. Donec placerat magna vitae elit interdum ornare. Mauris ullamcorper justo ligula, consequat posuere nunc ultrices ut.

Back of BIC Venturri
Back of speakers

Curabitur maximus tristique gravida. Vestibulum bibendum sagittis arcu finibus mattis. Proin at dui quis libero sagittis iaculis. Mauris ultricies eget lacus in volutpat. Praesent massa quam, varius ac sagittis sit amet, aliquam a turpis. Curabitur eu dolor lobortis, vulputate erat quis, semper tellus. Nam pellentesque tincidunt suscipit. Pellentesque molestie luctus urna. Phasellus ut vestibulum lectus. Sed tincidunt nibh ut tortor cursus, et finibus ante porta. Suspendisse condimentum arcu nec magna commodo aliquam. Sed mi diam, aliquet eget metus eu, iaculis sodales lorem. Curabitur vulputate accumsan dolor et maximus. Phasellus et cursus dolor. Phasellus feugiat ante est, pellentesque viverra urna dignissim ac.

Morbi ligula enim, laoreet et quam vitae, mattis blandit mi. Praesent faucibus nibh arcu, ac condimentum mi posuere in. Sed malesuada ac sem nec rutrum. Etiam condimentum lorem eget tincidunt rutrum. Aenean a ex velit. Pellentesque scelerisque enim sit amet efficitur cursus. Nam sed consequat nisl. Fusce interdum risus id facilisis fermentum. Etiam sit amet euismod lectus, quis efficitur enim. Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vivamus pretium sollicitudin aliquam. Aenean enim nibh, luctus sit amet ullamcorper sed, volutpat efficitur felis. Vivamus faucibus est vitae pulvinar luctus. Sed ut diam mi. Integer turpis augue, dictum vitae quam eget, tempor tincidunt purus.

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