Yes, I've had Olson on my ebay watchlist for a couple of years and those crop up often.Quote:
Originally Posted by struth
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Yes, I've had Olson on my ebay watchlist for a couple of years and those crop up often.Quote:
Originally Posted by struth
Removes the need for a 'balance' control. It's a neat idea. :)Quote:
Originally Posted by walpurgis
Are you sure it is the same company? I have a couple of their 13A socket distribution units and they are made in the UK.Quote:
Originally Posted by struth
yup afaik anyway. they started in about 1961 working from home. they made various things but are now big in pdu's and sell a lot to the nhs and for servers.Quote:
Originally Posted by Barry
Just messing about.
I've got a bunch of decent full range drive units that have not been used, so I'm doing a quick evaluation by mounting them in spare cabinets on temporary baffles, with some wadding added. I'm mainly listening for general tonal character and top end definition. No, I'm not doing anything 'by the book' here, but it'll give me an idea.
First up, 5.5 inch Chinese 8 ohm Aucharm units. These are very nicely built and finished, on a par with Coral and Fostex. They sound very punchy and clear, you'd not guess you were listening to such small units, no top end nasties at all either. Seem easy enough to drive, I think sensitivity is around 90db (I have the details somewhere).
https://i.ibb.co/RQ0TqGx/IMG-1331.jpg
I'll be trying 5.5 inch Canon units later, they should be nice too, I've used them before.
Now the Canon drivers. Used by Canon in their own branded speaker systems, quite probably from Taiwan or similar. These are actually 5.25 inch units and barely cover the baffle aperture.
Nowhere near as detailed or vibrant as the Aucharm units, less bass too. Can't really grumble though, I picked these up for a song ages back.
They go back into storage I think. I may have an idea for using them, I built two pairs into big folded horns years ago and that worked very well.
https://i.ibb.co/hF2jJLS/IMG-1332.jpg
Next, some vintage Eagle/Coral 6.5 inch 16 ohm extended range speaker units, not twin cone. I'll do 'em later.
probably the same unit used in the old S35? https://www.stereophile.com/standlou...non/index.htmlQuote:
Originally Posted by walpurgis
https://i.ibb.co/rt04nv5/canon.jpg
I believe it may be.Quote:
Originally Posted by Macca
Now playing with the old 6.5 inch Eagle/Coral drivers. I first had a pair of these around 1972, the twin cone version, marketed as the FR65, wish I'd kept them. They are single cone, extended range units with long throw doped fabric roll cone surrounds and are from the DL67 speakers system, I have a few 8 ohm pairs but these are the only 16 ohm ones which date from around 1968. Sounding extremely good, with no colorations standing out, firm and fast with good treble and detail. Could be the best tried out so far.
https://i.ibb.co/QMQ7z6Q/IMG-1336.jpg
https://i.ibb.co/0mLLQc3/IMG-1335.jpg
Playing a bit of classical through these now. Ina Boyle, Symphony No.1 "Glencree", sounds lovely. Great timbre, depth and detail, good weight too. I haven't even lagged the boxes properly or tuned the bass yet. Very nice.
Right, more playing around.
These 6.5 inch Chinese drivers up next, I'll need to do a bit of woodwork to fit them first. No idea what they'll be like, but they look decent.
https://i.ibb.co/4gT14mW/IMG-1338.jpg
https://i.ibb.co/TLBLT0z/IMG-1340.jpg
Are those whizzer cones Geoff? I don't know why exactly but they don't look quite the same as usual to me like they are too stiff or not wide enough or something. Maybe they will sound better than the usual ones.
I think they had a coaxial tweeter the S30s may have been the full range driver ones.Quote:
Originally Posted by Macca
I found this, but the whizzer cone looks white
https://images.app.goo.gl/yRdcgpez1vU4WFBu7
Edit: might be the S50s
https://www.audiosciencereview.com/f...-review.13982/
They are.Quote:
Originally Posted by Lawrence001
The parasitic cones on twin cone drivers seem to vary enormously in size compared to the main cone. I suppose it's all down to the maker's experimentation to judge what suits.
Right, back to driver comparisons.
The latest Chinese 6.5 inch units are performing very nicely in the try-out rig. Very clean top end and nicely detailed, bottom end is tight and punchy and there's definitely some decent transparency. Think I'll stick with these as a project for now. My valve amp should be happy with them.
https://i.ibb.co/7KRBkLC/IMG-1341.jpg
No info came with these, so I'll now have to poke around on the net to see if there are some specs around, if not, I'll figure it out.
(yes, I know the cable you can see is rubbish, it's just for a quick hook-up :))
Long overdue update to this blog.
My current speakers. They are homebuilt.
These are 1/8 wavelength transmission lines and are omnidirectional with upward firing 5.5 inch full range, dual cone Aucharm drivers, having a diffuser/reflector above them. They sound remarkably good and have much more weight to the presentation than might be expected and there is no shortage of detail. The omnidirectional characteristics do not detract from the ability to pinpoint the origin of sounds.
https://i.ibb.co/YFMrWcSW/DSC-0022.jpg
https://i.ibb.co/93r0DW0H/DSC-0024.jpg
https://i.ibb.co/DPzNb9BB/DSC-0026.jpg
https://i.ibb.co/JF5cKF5H/DSC-0027.jpg
https://i.ibb.co/jvqstkgZ/DSC-0028.jpg
https://i.ibb.co/d0fsC0Jp/DSC-0030.jpg
Nice build Geoff.
Ta Rob. :)
Looks like a professional build not DIY.
How did you make the diffuser?
Agreed!Quote:
Originally Posted by Macca
And how did you make the diffusers? I recognise the metalwork as possibly being protective grills taken from an electric fan, but the cones elude me.
Anyway, a lovely job - well done! :)
I made the diffusers by securing a long wood screw into the centre of the panel and moulded plaster around it to the approximate profile. Then using a profile template as a guide, sanded it into shape. The board was painted with PVA and the plaster applied while it was still wet. PVA was also mixed in with the plaster. The shaped plaster was impregnated with wood hardener to seal it and then sprayed white with matt acrylic paint.
That's what they are (computer parts) and they don't 'ring', there's a rubber damper on top.Quote:
Originally Posted by Barry
Before anyone asks. The cabinets are vinyl wrapped. It worked a treat!
Old school! I was wondering if you'd used a 3D printer.Quote:
Originally Posted by walpurgis
That would cost me £300, not the three quid I spent! :)Quote:
Originally Posted by Macca
Very neat work there, Geoff. I always admire folk who can build things:)
Hope they hit the spot for you and provide many happy hours of listening.
Marco.
Nice looking speakers.
Do you still have some Tannoy's hanging around? I fondly remember the cheviots you had many years ago.
S.
No Shane. The Tannoys were lovely, but too big for my current environment.Quote:
Originally Posted by southall-1998_mk2
Out of curiosity, I bought a Rotel RB-03 power amplifier off eBay, as the reviews claimed it was decent. Well it was mint and sounded vey good. Trouble is, there was some low level popping/crackling on the left channel. It goes back tomorrow. Not so good, I hate disappointments!
https://i.ibb.co/KctcQh3T/P1010413.jpg
Like with NAD, their older amps (1980s) were better.
I think you may be right.Quote:
Originally Posted by Macca
Do you still use a turntable, Geoff?
If yes, which one? And what arm/cart/stage?
S.
I have a turntable Shane, but it's stored at the moment.
A few years ago I treated myself to an old favourite, a mint Thorens TD150 Mk,II complete with TP13a tonearm and the now very rare original lid.
A simple old deck that always surprises me with how good they can sound.
I also have a selection of decent cartridges.
Did a tone test on the homebuilt speakers. Started with 100 Hz, then 75Hz and 50Hz, all sounded well defined. As did 45 Hz and I even got a solid output at 40Hz. 35Hz was audible but reduced and doubling was evident. No clear bass output at 30Hz.
A decent showing for a speaker with a 3.5 inch wide cone.
I did find that I can still hear up to 13kHz. Surprised me.
The 1/8 wavelength acoustic line is tuned to 40Hz and the driver resonance is quoted at 45Hz, so the port resonance falls slightly within the driver roll-off, which is OK.
https://i.ibb.co/rG4b09Gq/DSC-0022.jpg
(yes, I know the ancient carpet is horrible! :D)
Look like very respectable figures Geoff. Can you tell me a bit about the tone test and what's involved, I'm curious.
Quite simple. Use an online tone generator and hook up your PC or whatever device and take your pick of which tones you need.
You definitely want to go very easy on volume levels to start off. Only use sine waves, square waves and other can destroy speakers.
I used this: https://www.szynalski.com/tone-generator/
There are loads of sites for tone signals.
Thanks for that Geoff. I was mostly just curious about how bad my hearing was these days. I think you could probably hear pretty much any frequency if it's loud enough, so I just set the volume at 50% on my laptop and plugged my headphones in. Got to about 10kHz before it all went quiet, which was better than I was expecting.
Also I found that my puretone tinnitus is around 7kHz fwiw. I suppose I'd need to go for a proper hearing test to see if anything can be done about that. Might enquire about hearing aids anyway.
Sorry to be banging on about my hearing, but then you did name your thread 'Deaf row', so... :)
Very nice speaker build btw, they look shop-bought. With those diffusers, was that based on an existing design, or was it something you just thought you'd try out and see what happens? Either way it looks proper... and for 3 quid? I wish I had those kind of skills.
Well the diffusers cost around three quid and materials for the whole speaker build was probably somewhere a bit over £100.Quote:
Originally Posted by Pigmy Pony
Just a thought, perhaps your headphones lack output much above 10kHz. Some headphones don't extend up as far as you might expect, not that many might notice.
You reckon your DIY speakers sound (at least) as good as commercial speakers costing £500?
S.
£500 probably doesn't buy anything special in the way of speakers these days Shane. I'm thinking the sound quality I'm getting might cost more.Quote:
Originally Posted by southall-1998_mk2
Omni-directional speaker are a rarity. I can only think of MBL and Duevel as current makers, but no doubt there may be others. I have built some before and they were well liked by listeners.
Quote:
Originally Posted by walpurgis
Most modern speakers today are total rip-off. I can sort of understand why some people turn to DIY.
S.
Not according to Darko:Quote:
Originally Posted by southall-1998_mk2
https://darko.audio/2026/09/no-diy-s...lue-for-money/
Of course his job is industry promotion so he has to say that but his argument is that if DIYers costed their time then it's not economical. What he misses is that people DIY in their leisure time - time in which they would not be earning money anyway.
So if you DIY your speakers and save a grand over equivalent commercial product you were going to buy instead, you effectively made a grand in your leisure time where usually you'd make no money at all in that time. Win, win.
In my limited experience, omni-directional speakers are highly dependent on their surrounding environment. My only experience was with a Sonab design. I heard them sounding great at an audio and record dealer's premises, where they were located in a fairly small vaulted basement underneath the shop. Obviously the dealer had taken care both in choosing them and setting them up, but they worked really well.Quote:
Originally Posted by walpurgis
The second time was when a friend of a friend bought (or was given) a pair of Sonab speakers. Try as we might, we could not get them to sound right in the owner's fairly large living room. I wouldn't say they sounded awful but I wouldn't have been content.
I should add that the Sonab designs used several tweeters, whereas Geoff's design uses one drive unit: that could well make a difference.
I remember those Sonab speakers. I never heard any, and had no desire to. They would have to sound pretty special to justify those looks. They just looked weird.
This has now been replaced by an RB-850 power amp, which is in great shape and sounding very decent with the RC-960BX pre-amp. At slightly under £250 for this pair, it's tremendous value considering the sound quality provided.Quote:
Originally Posted by walpurgis
Along with my Rotel RA-04BX integrated, that completes the current foray into older budget gear. I do have more serious stuff, but I'm having fun with this lot :).
https://i.ibb.co/tdRTVq7/P1010417.jpg
Boot Sale Booty?
Four pairs of recently (very cheaply) acquired headphones.
https://i.ibb.co/cXc4gbny/P1010422.jpg
Nearest left, Philips EM 6146, dull sounding and not good, just as well they were only three quid.
Furthest left, Philips SHP 2500, awful! Thick and bassy with no definition or top end, Yuk! I wasted two more quid here. :rolleyes:
Nearest right, small JVC pair with no model number. They sound remarkable, a big surprise. Two nicker well spent! :)
Furthest right, small Lenco set, no model number. Again, very decent sound, slightly forward at the top, but OK. Nice and transparent, remind me of eighties Sennheisers. These were only 50p. :D
The last two pairs are definitely 'keepers', with the JVC top choice.
Not surprised the JVC are the best.
This is rather nice. Yes, I've been naughty again and bought another amp! :D
A rare, very late Quad 606 Mk.II power-amp, in black and grey with the later 909 type bevel edged casing. It's in amazing condition, as near immaculate as could be hoped for. With the later spec, it's more or less a 909 without the unwanted and occasionally problematic Quadlink circuitry. It's sounding excellent and totally silent mechanically. Nice.
https://i.ibb.co/N2w0CZdg/P1010429.jpg
Does look tidy, I never liked the graphics on those big QUAD amps though. I think they cheapen the look a bit.