Whether you are aware of it or not, you have attracted a few of the forum heavyweights here. Dissi's sim is rather interesting. It shows a typical midrange peak from the 0.9mH woofer which I would expect from a 1.8mH bass coil with a 4.7uF rolloff. You need a 3:1 ratio to lose the shunt resistance.Cheers and thank you, all of these very helpful options are being collated and will be offered to the guy I know.
It's obvious this isn't my area of expertise, I'll put up a couple of photos tomorrow that shows where I fit in to DIY audio
http://www.diyaudio.com/forums/multi-way/270818-changing-out-scanspeak-tweeters-2.html#post4249996
If the baffle width is a mere 22cm, you might expect some dropout around 200-500 Hz. 30cm works better. 1.8mH is quite high bafflestep for an 8" speaker too. I hate lumpy low bass myself. It intrudes when the speakers are near a wall. I'd probably try a smaller coil and a bigger capacitor.
What's the way forward for a guy here with an evidently deep wallet and some goodish drivers? Frankly, hear one soft dome and you've heard them all. While they behave well near the voice-coil. In the centre of the dome they are just producing noisy mush above 7kHz.
TBH, my ears have taken a hammering over the years too, thankyou to Ducks Deluxe in small venues and windblast from motorcycling. Nevertheless, I still appreciate drivers that resolve detail.
If I was you, I'd try a metal tweeter like this H1212-06 27TBFC/G with a 6.8R and 0.68uF Zobel. Or that Vifa XT25.
Or weirdly, this little £7 Monacor HT22-8 cone cheapie which is about 90mm diameter. Dispersion sucks, but detail shines.
HT-22/8
Or persist with your current circuit with a bit of bass shunt resistance to lose the mid peak and a Zobel rather than the 5.6R and 0.3mH series element. The red resistor is tweeter level. It's adjustable. Every ohm at the input resistor adds about 1dB attenuation.
The fact is that with a 3kHz crossover, the woofer is doing most of the work. Tweeters just add air. I found this out by just putting my hand over the tweeter.
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Yes, that's a point I thought about making myself, the system is "for my ears only" so to speak, I actually have hearing aids which I loath using but due find useful for TV, where I'm not actually that concerned about quality.
And believe me what you hear through those things is artificial beyond belief.
And yes, I do realise that I'm getting replies from some staunch members here, I have dropped in from time to time and have picked up on many of the names simply from googled questions. It is all greatly appreciated, I hope I haven't given the impression it isn't, it's just that as you probably realise I don't fully appreciate some of the comments that you guys take as read.
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Sub is another Wilmslow design with a 200 watt british built amp on board and Volt 250.1 unit. Headphone stand was mage 40 years ago from 12" x 4" reclaimed 19th century ships timbers.
Must use exterior grade varnish with a uv protector in next time, speakers are 20 years old, sub is about 6, note the lack of fade to the speakers.
Sub has 6mm square oak let into all corners to take ant knocks being floor standing.
Stands are again home made, 3 x 100mm x 4mm wall stainless steel and sand filled, top/bottom plates 8mm aluminium.
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Well, it's evidently time to earn some NEW skills then! Nice old speakers, BTW.
Crossovers modifications aren't hard. You'll need to buy a 40W soldering iron and some lead-free solder at Maplin. It should be tinned the first time it warms up. Wirewound resistors and coils are tough as old boots, but you should work fast (say 5 seconds at most) with capacitors. Old oxidised components should be scraped to fresh metal for a good join.
Some cutting and gripping tools are useful. Long nosed pliers and cutters.
Capacitors: LCR Audio-Grade Polypropylene Axial 630V 680nF Capacitor | Maplin
Resistors: Wirewound 10 Watt 6.8 Ohm Resistor | Maplin
Hook up wire to bypass: 5A/15A/30A Fuse Wire 3 Pack | Maplin
Tagstrip: http://www.maplin.co.uk/p/5-way-tagstrip-fm34m
I buy big reels of tinned 30A fuse wire. It's actually pure copper and just the job. There's a good trick with crimping connectors, double the wire back to get it fat enough for a good crimp.
Crossovers modifications aren't hard. You'll need to buy a 40W soldering iron and some lead-free solder at Maplin. It should be tinned the first time it warms up. Wirewound resistors and coils are tough as old boots, but you should work fast (say 5 seconds at most) with capacitors. Old oxidised components should be scraped to fresh metal for a good join.
Some cutting and gripping tools are useful. Long nosed pliers and cutters.
Capacitors: LCR Audio-Grade Polypropylene Axial 630V 680nF Capacitor | Maplin
Resistors: Wirewound 10 Watt 6.8 Ohm Resistor | Maplin
Hook up wire to bypass: 5A/15A/30A Fuse Wire 3 Pack | Maplin
Tagstrip: http://www.maplin.co.uk/p/5-way-tagstrip-fm34m
I buy big reels of tinned 30A fuse wire. It's actually pure copper and just the job. There's a good trick with crimping connectors, double the wire back to get it fat enough for a good crimp.
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Well, it's evidently time to earn some NEW skills then! Nice old speakers, BTW.
Crossovers modifications aren't hard. You'll need to buy a 40W soldering iron and some lead-free solder at Maplin. It should be tinned the first time it warms up. Wirewound resistors and coils are tough as old boots, but you should work fast (say 5 seconds at most) with capacitors. Old oxidised components should be scraped to fresh metal for a good join.
Some cutting and gripping tools are useful. Long nosed pliers and cutters.
Capacitors: LCR Audio-Grade Polypropylene Axial 630V 680nF Capacitor | Maplin
Resistors: Wirewound 10 Watt 6.8 Ohm Resistor | Maplin
Hook up wire to bypass: 5A/15A/30A Fuse Wire 3 Pack | Maplin
Tagstrip: 5 Way Tagstrip | Maplin
I buy big reels of tinned 30A fuse wire. It's actually pure copper and just the job. There's a good trick with crimping connectors, double the wire back to get it fat enough for a good crimp.
Yep, had a smile at that.
Ex heating/plumber type guy, have the soldering bit, have but that's easy. 1/2" copper to old lead pipe is my forte. But I should keep on track.
Did a 2 week course on basic safe electrics and an add on of 2 days electronics, most went away with the years but I do have some basic understanding. Only concern is I don't have a sucker punch to go with all this
The sucker punch, given that the art has evolved over the last 20 years, is probably the Harbeth Monitor 30:
6moons audio reviews: Harbeth Monitor 30
Metal SEAS tweeter. I rest my case.
6moons audio reviews: Harbeth Monitor 30
Metal SEAS tweeter. I rest my case.
Well, finally got around to sorting this today.
End result is I'm now convinced that any additional effort in the upper frequency are is un-needed.
Direct changover gives a 25% increase, measured by my ears, level of upper piano, symbols etc. IE I can now just hear them, forget abrasive/smoother, I now just have some.
Did play around with a new CD frequency test disc I have had for a while but never bothered with.
Set up at a constant level that is my normal listening comfort zone, 5000hz is fading, 6200 is at the limit of my hearing and further is gone
So efforts now being made lower down and will concentrate on the bass/mid, a question about which I have seperated out for simplicity.
Thanks gain,
End result is I'm now convinced that any additional effort in the upper frequency are is un-needed.
Direct changover gives a 25% increase, measured by my ears, level of upper piano, symbols etc. IE I can now just hear them, forget abrasive/smoother, I now just have some.
Did play around with a new CD frequency test disc I have had for a while but never bothered with.
Set up at a constant level that is my normal listening comfort zone, 5000hz is fading, 6200 is at the limit of my hearing and further is gone
So efforts now being made lower down and will concentrate on the bass/mid, a question about which I have seperated out for simplicity.
Thanks gain,
I'd agree that if you really aren't hearing a test tone at 6.2kHz, there really isn't much point in doing anything to the tweeter. Shame.
Just looking at that 1.8mH bass coil, I'd reckon these speakers will be overly bassy. Sort of thing you can't put near a wall. Might be worth trying just stuffing the port with a pair of socks, and getting nearer closed box.
These days, I tend to use 1mH or less with a bit of resistance in the bass shunt. Maybe 6.8uF and 3 ohms in your case. That sounds louder in the midrange, so you'd also increase tweeter level a tidge.
Just looking at that 1.8mH bass coil, I'd reckon these speakers will be overly bassy. Sort of thing you can't put near a wall. Might be worth trying just stuffing the port with a pair of socks, and getting nearer closed box.
These days, I tend to use 1mH or less with a bit of resistance in the bass shunt. Maybe 6.8uF and 3 ohms in your case. That sounds louder in the midrange, so you'd also increase tweeter level a tidge.
Thanks Steve,
Yes, I hadn't really realised how abrupt "my" drop of was, I actually took that disc to a friends to try on a different system just to make sure it wasn't a crossover issue at my end. Same result at his end so have to accept that my listening is always going to have limitations.
Good news is that it doesn't stop the enjoyment of music, you just keep thinking "I know there is a low level vocal in there"
My classic example is on Supertramp's Crime of the Century, a record I played a lot back in the day.
On the title track the last line as the vocals fade out is '' ....there's you and there's me, that can't be right?"
That bit has gone, I just add it mentally
I've printed all the suggestions and will chat with my man, he will have all the caps and resistors on the bench and be far more able to mess around than I.
thanks again to all.
Yes, I hadn't really realised how abrupt "my" drop of was, I actually took that disc to a friends to try on a different system just to make sure it wasn't a crossover issue at my end. Same result at his end so have to accept that my listening is always going to have limitations.
Good news is that it doesn't stop the enjoyment of music, you just keep thinking "I know there is a low level vocal in there"
My classic example is on Supertramp's Crime of the Century, a record I played a lot back in the day.
On the title track the last line as the vocals fade out is '' ....there's you and there's me, that can't be right?"
That bit has gone, I just add it mentally
I've printed all the suggestions and will chat with my man, he will have all the caps and resistors on the bench and be far more able to mess around than I.
thanks again to all.
Thanks Steve,
Yes, I hadn't really realised how abrupt "my" drop of was, I actually took that disc to a friends to try on a different system just to make sure it wasn't a crossover issue at my end. Same result at his end so have to accept that my listening is always going to have limitations.
Good news is that it doesn't stop the enjoyment of music, you just keep thinking "I know there is a low level vocal in there"
My classic example is on Supertramp's Crime of the Century, a record I played a lot back in the day.
On the title track the last line as the vocals fade out is '' ....there's you and there's me, that can't be right?"
That bit has gone, I just add it mentally
I've printed all the suggestions and will chat with my man, he will have all the caps and resistors on the bench and be far more able to mess around than I.
thanks again to all.
Crime of the Century was a great dynamic piece of vinyl, that got ruined on transfer to CD where all the dynamics were compressed. It was an unusual Left, Right and Centre mix that broke the usual rules of pan-pot mixing. I believe it has finally been remixed to CD in 2014 to get back the original sound.
That's a new speaker. And I thought you had new 90dB Scanspeak D3004-662001? Have you fitted them yet? Had a listen?
I remain of the opinion that adjusting the bass filter for less bass would sound much better. It has the effect of bringing up the midrange. I would try 1mH with 2.7 R and 8.2uF shunt. Then reduce the tweeter input resistor to 1 ohm.
It's a little softer than my usual taste but the dynamics of the piano made it my equipment auditioning disc in the 70's, I liked to be able to follow every rhythm on that track and only gear that had real separation could do that.
Yes the tweeters have been changed, my comment in the earlier posted were based on that.
And yes, I maybe have the bug again simply through talking this over with you guys, maybe new speakers are on the agenda. I really love the bottom/mid of the units I have, but do use the sub I pictured earlier to get down lower. I'd like, and so would my wife, to dispense with that.
Wilmslow do a kit based on the ATC 100, using the same ATC bass and mid which unfortunately I haven't heard in either active or passive form, they don't have them on demo either so I'm open to any considerations at present...
And yes, I do seem to be firing in several directions at once
I mostly get involved in the mostly demented and tirelessly repetitive threads at DIYAudio because something, "Je ne sais quoi" as the French say, interests me.
This one is actually quite interesting. The Volt BM220-8 0hm is a modern recreation of your classic plastic polycone in the KEF B200 tradition.
Volt Loudspeakers | BM220.8 (8″)
It's quite well-behaved, as evidenced by the 1.8mH/4.7uf bass crossover with no shunt resistance. What's wrong with it is the awful choice of a soft-dome tweeter. Frankly these things stink. Er, IMO.
You can't correct hearing loss at HF with treble boost. It's simply inaccurate.
Much better, would be to use a ring radiator like the Vifa XT-25:
An externally hosted image should be here but it was not working when we last tested it.
I say that having never heard one in my life. It's just theoretically better.
Below my 8" bass epiphany, the paper bass flat baffle KEF Celeste 3, a BW3/LR4 hybrid with negative polarity on the tweeter. And a physically time aligned KEF modification to the polycone 8" B200 with a Vifa XT-19 ring radiator to show there's many ways to skin a cat.
That Wilmslow design is rather good IMO, except for the choice of tweeter.
Hi Steve, out of interest, the crossover in the image is for an enclosure of 30L@37Hz. What deficiencies would you anticipate if you were to change the enclosure to 50L@30Hz
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