Speakers I Built in my Bedroom

[ElectroMan]

I have threatened, a few times, to post some photographs of the speakers I built in my bedroom about 30 years ago.

They were a pair of large transmission line speakers designed by Chris Rogers, the Pro-9TL. The plans were originally published in Practical Hi-Fi magazine, and were I believe based on earlier designs printed in Hi-Fi Answers and elsewhere.

This is some of the wood, fresh from a timber merchant, plus assorted tools.

If anyone is remotely interested in this, I have more photographs of each stage of construction, and the finished articles.

 

[matthewpiano]

Would love to see more. Looks fascinating. Nice to see the Thorens box in the corner too!

 

[Messiah]

Would love to see the rest........

 

[Olli1324]

Another vote for the rest of the pictures!

 

[Anonymous]

ditto

 

[Anonymous]

Do show but tease us a bit, maybe a daily update !!

 

[bretty]

I'd like to see the other shots.

I have some Rogers myself. I bet yours sounded amazing, right?ÿ

 

[ElectroMan]

matthewpiano:Would love to see more. Looks fascinating. Nice to see the Thorens box in the corner too!

Glad someone noticed the Thorens!

It was a TD160, I think, with a Goldring cartridge. How I wish I still had it!

Unfortunately, I 'upgraded' it to a direct-drive turntable (Direct Designs, a British company who bought in a Japanese drive and mounted it in their own deck). This was when direct-drive was all the rage, and the turntable got a great review in a hi-fi mag (not WHF).

Basically, it was cack! The first sample had to be replaced as the much-vaunted speed accuracy was way out, with the speed varying wildly as a record was playing. The second sample was better, but not much.

After this, I think I put a Connoisseur turntable into a home-made plinth. I can't remember the arm, but it used silicon damping fluid in a partly transparent housing (I think). I've searched through lists of tonearm manufacturers and none of them ring a bell!

marvsins:Do show but tease us a bit, maybe a daily update !!

A good idea (though some may liken it to slow torture).

bretty:

I'd like to see the other shots.

I have some Rogers myself. I bet yours sounded amazing, right?

I don't think Chris Rogers was connected with Rogers the company?

The Pro9's had amazing bass - I had previously used bookshelf speakers (before stands were generally used), so the depth and 'size' of the sound was a revelation. But I expect yours are much better made!

This shows the side panels marked out, with one fitted with wooden battens. I eventually borrowed an electric drill from a friend, as I didn't realise how many screws would need to be fitted!

(Apologies for the net curtains, but it was the 'Seventies and I was living at my parents'!)

 

[bretty]

Oops, my mistake. Confusing Chris with Jim. I'm gonna shut up, now. But before I do, I want to say great shots, keep em coming.

 

[ElectroMan]

Thanks for the comments.

Apologies for the less than perfect quality of the pictures, but they were scanned in from old black & white prints as I made a long time ago!

This is one of the cabinet shells, ready for the back and internal panels.

 

[floyd droid]

This could turn out to be a classic thread methinks,great stuff. I think the wallpaper in the 2nd pic must be the 'every home must have it' design of the 70s.

 

[ElectroMan]

I thought I ought to apologise for the wallpaper too!

And the flowery thing in the previous picture is a tubular, vinyl-framed wardrobe (flower power and all that).

This is after all of the internal bracing battens and panels were fitted, waiting for the wood glue to dry out.

Note the integral solid wood block floor stand!

 

[Anonymous]

This is really interesting. Look like a lot of work though.

 

[ElectroMan]

I suppose it took about a month to finish the cabinets, and about as long to clean up!

I remember I had to wait a while to get both sets of drive units, and crossovers, which was quite frustrating. I also remember being dumped on by a pigeon as I was waiting for a bus home with a large box of parts in my hands!

 

[Anonymous]

One of the great ongoing threads here I see. I've been looking into 'Ikea' speakers myself only recently, I adore the satisfaction involved in constructing your own pleasure. I've always had the intention of buying a Caterham at some point, though I'm at a loss at the moment given my lack of garage and vehicle assembly tools.

Looking forward to your future posts!ÿ

 

[ElectroMan]

I believe you can get cabinets in kit form now for DIY speakers - I gave the cutting plan from the magazine to a timber merchant, and not all the pieces were exactly the right size, but I managed to get them to fit together!

You could always start small with your Caterham, like this!

This is one of the cabinets completed so far as the woodwork is concerned, with internal panels and bracing.

 

[ElectroMan]

This is a close-up of the top section, showing how the internal 'labyrinth', or folded tunnel, is laid out, to (greatly) increase the bass output.

There are more panels to be fitted after some internal sound deadening has been applied ...

 

[ElectroMan]

Some more wood fitted, plus a bitumen sound deadening panel.

 

[floyd droid]

Keep em coming mate,despite this being the first response to your last 3 pics,and i hope i speak for others,we are still out here watching and waiting.

 

[ElectroMan]

Cheers - let me know when it becomes too much to take!!

 

[Dave_]

Yep, agree with floyd droid keep 'em coming!

 

[Olli1324]

I have been lurking too 😉

 

[ElectroMan]

Thanks for all the encouragement!

 

[ElectroMan]

Here we have one of the front baffles, plus the drive units and crossover:

The bass driver was a Kef B139, the midrange by Peerless, and the tweeter an Audax (I think).

The midrange had special 'doping' applied and was only available through two or three specialist suppliers. It was a few months before I could get hold of them.

Like rest of the cabinet, apart from the battens, the baffle was made of chipboard. It was quite an effort to cut out the holes, and chamfer them with a chisel!

 

[ElectroMan]

Ordinary carpet felt underlay was used as basic damping: