Official Semi-Omni Metronome Build Thread.

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Cressy Snr
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#1 Official Semi-Omni Metronome Build Thread.

Post by Cressy Snr »

So at last I'm ready to do a proper official build thread on the semi-omni, folded Metronome.

Mind you, it didn't get off to a good start this morning, as I couldn't for the life of me, find my red book with all the build data in it. In fact I still can't find it, so I ended up having to reverse engineer the prototypes to retrieve all the dimensions. Talk about absent-minded professor mode! :lol: :lol:

Anyhow! these ones are for my own use, and will be veneered in African walnut and waxed. These, once in my own system, will release the fully run in prototypes. I know Simon has asked to hear to hear the prototypes, so once the new ones are built, and in my own system, you can have the prototypes for a week at home Simon.

I should be around a fortnight at the most, building the newies and will detail them on this thread.
Will do some nice, spring woodland photography featuring the newies.
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simon
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#2 Re: Official Semi-Omni Metronome Build Thread.

Post by simon »

Thanks Steve, I do appreciate that. I'd hoped to hear the OTLs too before they went to their owners but time is against me at the moment. Still the decorating campaign is progressing reasonably well...
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#3 Re: Official Semi-Omni Metronome Build Thread.

Post by Cressy Snr »

No problem Simon. :)

Now, seeing as there is only one component apart from the drivers, ie a cap to keep bass out of the tweeter, I splashed out a bit on the caps; a nice pair of Mundorf Mcap Evo, silver gold foil in oils, courtesy of Hi-Fi Collective.
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#4 Re: Official Semi-Omni Metronome Build Thread.

Post by IslandPink »

Top notch !
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Thermionic Idler
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#5 Re: Official Semi-Omni Metronome Build Thread.

Post by Thermionic Idler »

Gotta love a crossover that consists of one component.
Deck: Garrard 301 - Audio Origami PU7 - NW Analogue DH3S
Phono: Pete Millett LR, Lundahl SUT, AMB σ22 PSU
Linestage: Bruno Putzeys Balanced Pre + Hans Polak relay mod, LCDuino control
Power amps: 300B PP 'Symmetric Reichert'
Speakers: FF225WK Big Mets
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Ray P
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#6 Re: Official Semi-Omni Metronome Build Thread.

Post by Ray P »

Cressy Snr wrote: Mon Mar 13, 2017 1:26 pmMind you, it didn't get off to a good start this morning, as I couldn't for the life of me, find my red book with all the build data in it. In fact I still can't find it, so I ended up having to reverse engineer the prototypes to retrieve all the dimensions. Talk about absent-minded professor mode! :lol: :lol:
Don't worry Steve, it'll be right in front of you when you least expect it - that's the voice of experience!

Looking forward to following this build and hearing a pair at Owston.

Ray
Sorry, I couldn't resist!
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pre65
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#7 Re: Official Semi-Omni Metronome Build Thread.

Post by pre65 »

It happens to me as well Steve. I can't believe the large number of things I've lost, or mislaid over the years. :(

Most of them turn up, eventually. :)

I find that when searching for something I've lost today, I find the thing I lost two weeks ago. :lol:
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G-Popz THE easy listening connoisseur. (Philip)
Cressy Snr
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#8 Re: Official Semi-Omni Metronome Build Thread

Post by Cressy Snr »

Ray P wrote: Tue Mar 14, 2017 7:17 am
Looking forward to following this build and hearing a pair at Owston.

Ray
Yes,
I'm quite looking forward to taking some speakers to Owston, that actually fit in the car. :lol:
pre65 wrote: Tue Mar 14, 2017 8:47 am It happens to me as well Steve. I can't believe the large number of things I've lost, or mislaid over the years. :(

Most of them turn up, eventually. :)

I find that when searching for something I've lost today, I find the thing I lost two weeks ago. :lol:
Found it right at the back, under the sofa, though how in God's name got there, I've no idea :|
Thermionic Idler wrote: Mon Mar 13, 2017 11:46 pm Gotta love a crossover that consists of one component.
Yes, a single cap works brillantly in some situations.
Up - firing semi-omnis like the OmniMets, the Doc's Cubes, and your forward firing main driver modded Mets all seem to benefit greatly from keeping crossovers as simple as possible. Another plus is that having only a cap means you can spend a bit more for a quality component.
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#9 Re: Official Semi-Omni Metronome Build Thread.

Post by Cressy Snr »

Not a lot of progress last week; I marked out one panel and that's all I got done, but I've almost completed the marking out of all the panels now.
Should be able to get cutting tomorrow, providing the agency don't phone, wanting me to work.
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#10 Re: Official Semi-Omni Metronome Build Thread.

Post by Cressy Snr »

One marathon hand sawing session later, and we have a complete kit of parts for another pair of OmniMets.

Image

Assembly starts tomorrow. :)
Last edited by Cressy Snr on Tue Mar 21, 2017 7:03 pm, edited 1 time in total.
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#11 Re: Official Semi-Omni Metronome Build Thread.

Post by Cressy Snr »

Look at the waste generated by that one speaker cabinet.
Image
That waste is why no mainstream maker would touch this design with a bargepole.
Suits me fine.
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#12 Re: Official Semi-Omni Metronome Build Thread.

Post by simon »

That's a LOT of handsawing Steve!
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#13 Re: Official Semi-Omni Metronome Build Thread.

Post by Nick »

That waste is why no mainstream maker would touch this design with a bargepole.
I would have thought those shapes would tile nicely to fill a sheet of ply.
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#14 Re: Official Semi-Omni Metronome Build Thread.

Post by Cressy Snr »

simon wrote: Tue Mar 21, 2017 11:29 pm That's a LOT of handsawing Steve!
Yes... the production method is, shall we say, labour intensive :wink:
Nick wrote: Tue Mar 21, 2017 11:45 pm I would have thought those shapes would tile nicely to fill a sheet of ply.
Aye, that was a stupid comment I made. A computer would generate a much more economical cutting list from a sheet of 8x4 and a power tool would make short work of the sawing.

I do like the feel of the hand saw though, and it's good exercise. :)
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#15 Re: Official Semi-Omni Metronome Build Thread.

Post by Cressy Snr »

Hand tools used for this project.
Image
Top is, My late Dad's Stanley No 5 jack plane for planing angles onto the edges of the pieces. I know... a table saw would do the job ten times as quick and that's what is really needed to be honest; can't keep messing about like this, need to get with modern times, but the plane is such a satisfying thing to use and produces true edges, straight as a die.

Middle, Dad's old 1960s cutting gauge to cut lines and make sure I'm taking off exactly the same amount off each edge, when planing the angles.
And the modern Stanley block plane for fine trimming.
Last edited by Cressy Snr on Thu Mar 23, 2017 7:35 pm, edited 2 times in total.
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