With regards to the passive xover have you ever resolved the problem that the ATC from the Gold is 16Ohm while the Platinums Volt is 8Ohm?
The Volt dome has a Qts of 0.75 according to manufacturers figures btw.
Volt Loudspeakers | VM752 (3″ Midrange Dome)
The Volt dome has a Qts of 0.75 according to manufacturers figures btw.
Volt Loudspeakers | VM752 (3″ Midrange Dome)
It is very easy nowadays to do some measuring. Any decent sound card
for about 30 quid, HOLM Impulse ( free software), a measurement mic
(Behringer),phantom power supply (a couple of resistors, caps, jacks,
9V battery) and a single channel amplifier with volume control and you
are set.
for about 30 quid, HOLM Impulse ( free software), a measurement mic
(Behringer),phantom power supply (a couple of resistors, caps, jacks,
9V battery) and a single channel amplifier with volume control and you
are set.
I was assured by WA that I had the Platinum crossover not the gold but I have been onto them to check.
With HOLM you are measuring impulse response and the software
calculates frequency response, phase and distortion. You will then
see exactly how your XO filter and drivers work together.
calculates frequency response, phase and distortion. You will then
see exactly how your XO filter and drivers work together.
really sad to hear your disapointment but not at all surprised, as you point out you were looking for a proven design - you shouldn't have to mess around with this. Unfortunately my experience with all the WA designs I've seen is that they suck at crossover design, and generally produce poor sounding speakers that should blow you away if you look at the sum of the parts (whilst PMC produce astounding speakers with cheap parts through excellent design and tollerence standards)
I have personal reasons why I prefer passive crossovers to active, so at this stage I'd be working on a passive xo, however if you're going to go active there's no reason to measure everything, you just need a measurement mic and to measure FR with your active units.
What are your plans now?
I have personal reasons why I prefer passive crossovers to active, so at this stage I'd be working on a passive xo, however if you're going to go active there's no reason to measure everything, you just need a measurement mic and to measure FR with your active units.
What are your plans now?
I've got an awful lot of work to do before the active idea comes to life.
In the meantime I need to get the passive setup working.
In the meantime I need to get the passive setup working.
The Volt VM752 dome has a sensitivity of 92db based on the spec when I bought the unit. (The latest spec said 94db). I think you really need to have both of your speaker setup to do the listening test.
I drive my Volt actively and I do not find it less sensitive compare to other mid dome I have such as the Dynaudio Escotar M560. I find the sound quality of the VM752 on par with the Escotar.
Let the beast run for a while and let us know how it is doing. Good Luck
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Yeah... You're not in a good place.
I'm running some sims to see what I can come up with based on the manufacturers data, but these certainly arn't any easy set of driver to integrate... some drivers just play nice together, some don't. These don't... I'll update with a post of some potential schematics for you in a while
I'm running some sims to see what I can come up with based on the manufacturers data, but these certainly arn't any easy set of driver to integrate... some drivers just play nice together, some don't. These don't... I'll update with a post of some potential schematics for you in a while
It strikes me as more likely that something is not working as intended because of a mistake. A straightforward way to determine this is to measure the on axis frequency response and then investigate further based on what you find. If you opt to DIY then being able to perform diagnostics like this is pretty much a requirement if quality is at all important. A reasonable measurement system will cost less than £100 with an uncalibrated microphone.
Yeah... there is that, the B&W mid unit is superb.
Did you try swapping the polarity of the speakers and listening in stereo yet, or just in stereo for a while? I think we need to establish that the current solution is invalid before pushing forward with a new one.
I've modelled what you have based on manufacturer data, as I said these drivers don't play nice together at all.. the more I look at it, the more confused I get, really very tempting to suggest we change the tweeter, but before that we need to look at the measurements of the drivers in the boxes, there's a lot of anomalies with the simulation, I could give you a "will sound ok given variables and not to costly" design to test agains, which is 2nd order electrical throughout, with an inverted mid and zobel on the bass, but the impedance isn't anything like what I'd want to see for any design I would personally sell.... and it presumes that the manufacturer data supplied is accurate.
Problem is even for mid-range crossover components this 'cheap' solution is gonna cost about £160, though a cheap version could be made to test, and then if it works you're probably going to want the more complex crossover design I was working on, which was much better but had about 27 components per side, as opposed to 13, which also means higher values and cost for the caps... but would sound superb if the measurements are correct...
Which leaves us in the same place, build the stereo pair, listen to them, try switching the polarity on the mid and trebble (or just the bass) and listen again.
If you're definately not happy we need to measure the things!
Did you try swapping the polarity of the speakers and listening in stereo yet, or just in stereo for a while? I think we need to establish that the current solution is invalid before pushing forward with a new one.
I've modelled what you have based on manufacturer data, as I said these drivers don't play nice together at all.. the more I look at it, the more confused I get, really very tempting to suggest we change the tweeter, but before that we need to look at the measurements of the drivers in the boxes, there's a lot of anomalies with the simulation, I could give you a "will sound ok given variables and not to costly" design to test agains, which is 2nd order electrical throughout, with an inverted mid and zobel on the bass, but the impedance isn't anything like what I'd want to see for any design I would personally sell.... and it presumes that the manufacturer data supplied is accurate.
Problem is even for mid-range crossover components this 'cheap' solution is gonna cost about £160, though a cheap version could be made to test, and then if it works you're probably going to want the more complex crossover design I was working on, which was much better but had about 27 components per side, as opposed to 13, which also means higher values and cost for the caps... but would sound superb if the measurements are correct...
Which leaves us in the same place, build the stereo pair, listen to them, try switching the polarity on the mid and trebble (or just the bass) and listen again.
If you're definately not happy we need to measure the things!
Given the lack of satisfied feedback on the current incarnation of wilmslow audio is this most likely? I know people on this forum are a fussy bunch, but have yet to find someone jumping up to say how brilliant their current kits are...
I had a very rough look at your speaker, and that midrange crossover certainly doesn't inspire confidence. I don't know why that 100uF is there at all, and it's certainly not a classic topology. The speaker is quite like a Celestion Ditton 66.
Which could do some very nice phase alignment with a bit of tinkering, although it had midrange diffraction problems on a wide baffle IMO.
The only way to approach a 3 way is to set up the midrange response first, then build the bass and tweeter around it. Target response, in other words. Steen Duelund worked out some solutions.
Just thinking aloud really.
Which could do some very nice phase alignment with a bit of tinkering, although it had midrange diffraction problems on a wide baffle IMO.
The only way to approach a 3 way is to set up the midrange response first, then build the bass and tweeter around it. Target response, in other words. Steen Duelund worked out some solutions.
Just thinking aloud really.
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The OP said the sound was rubbish not that is was a bit different and not quite as good as his current speakers. The drivers are good, the cabinet looks fine, the crossover may well be improvable but if assembled correctly with the right value components should be at least reasonable. I cannot see how this can add up to rubbish unless something is wrong and, to be blunt, the OP should not expect his efforts to come together perfectly first time since they rarely do for the rest of us.
Cost isn't too much of an issue but I am completely new to DIY speaker design.
I'm waiting on a few minor parts so that I can complete the second speaker, simple things like turret nuts.
I'm waiting on a few minor parts so that I can complete the second speaker, simple things like turret nuts.
And he is not the first to be dissatisfied with WA. I asked if anyone had ever posted that WA had delivered something that was good. I have only seen positive feedback on the WA site, so I wonder on what evidence you base your conclusions? One would expect a £2600 kit to be good 'out the box' so I think the OP is right to be frustrated.
I am basing my conclusions on experience of what happens in the real world when we DIY, what the OP has stated his speakers sound like and the likelihood of a company that has been in the speaker business a long time marketing a very expensive kit that sounds like rubbish compared to something being wrong. The advice that the clearly inexperienced OP is being given concerning changing the passive crossover before he has found why his poorly performing speakers are performing poorly is not good in my opinion. Whether the design is as good as it should be is a separate issue.
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