so with my Kludge, being monopole bass, perhaps a sort of dipole mid and monopole tweeter i am not gong to get that whatever the effort!.........?
To be fair to it, it sounds quite open and imaging has some tolerance of position, but without A/B my memory wont discern whether that's better than the original Fusion before cannibalisation!
SL did some speakers without dipole bass though, i think....or did he move on from there...
To be fair to it, it sounds quite open and imaging has some tolerance of position, but without A/B my memory wont discern whether that's better than the original Fusion before cannibalisation!
SL did some speakers without dipole bass though, i think....or did he move on from there...
Avoid treating your room as any treatment that absorbs early reflections will interfere with the sort of effects being described there. Try and place the speakers to avoid reflections at less than 6ms. This sounds great when described like that but I find it to make studio recordings much less pleasing.
It doesn't seem too hard to work although it is not as intuitive as other software I have used. I have got a 24dB LR Crossover in the screen shot attached below.
To measure the woofer alone just disconnect you mid tweeter speaker cables and to measure the mid alone turn the Hypex off 😉
To measure in room move a speaker to the centre of the room raise it off the ground and put your absorbent panels on the floor between the speaker and the mic. Gate the response before the first reflection by looking at the impulse response. For the woofer leave it on the floor and take nearfield measurements of the driver and port output to combine together. Jeff Bagby has a good guide to Quasi Anechoic measurements.
Outside or groundplane are also good options but are not always possible depending on where you live.
What you have is interference between the two drivers, moving the crossover up a bit won't really fix that. It might help but what you need is a woofer filter that works with the new mid response.
Attachments
I would not say that the sort of sound your are looking for is only to be found in dipoles/open baffle speakers.
Many who desire it gravitate towards them but it is not a prerequisite.
The interaction between speaker and room is a complicated one.
Is the amp happy only driving a part of the load, be it active through Hypex on the woofer or passive to the mid or tweeter?
I have never weighed the Fusions but my guess is > 60kg, they were assembled upstairs here because of that, no chance to get outside and difficult to raise but i will have a go at that!
Yes, there are already driven separately the high level input is just that.
You don't have to raise the speakers at all but it might cut down the reflection free time and therefore reduce the resolution of the measurement.
I had kept this thread updated to a point and was grateful to the many respondents but went off air when I started to consult in more detail by email with Fluid who generously gave me advice and patiently coached me through learning quite a lot and experimenting in some well targeted areas.
It’s clear I have learnt a little and enjoyed the process.
My original question was OB or box and through the process of using the same components that I had built up as the excellent Fusion BAD design by Troels Gravesen mounted with mid and tweeter OB I was coached through some modifications to the OB and some more detailed work on the active bass:mid crossover and the EQ in the bass range up to that frequency.
I started with a baffle as designed for the Fusion mid and treble but with no box and the bass from the separated Fusion ported box.
We added some short wings round the mid to fill a little of the bass to mid crossover dip that appeared with the mid OB.
We aligned vertically the bass (in front of the OB) and put in delay to time align the drivers.
We raised the crossover frequency and applied some EQ to the bass and gradually got a good flat FR and more coherent sound.
It was an experiment, not a refined design, but we coaxed out of it quite a respectable FR and result, it was good to listen to. It was surprising how much difference small adjustments could make.
In the end I believe I learnt to like the presentation of mid and treble it gave, even though my OB was only possibly dipole in the mid range and I may come back to that principle in the future.
However, perhaps more importantly I learnt new things and had several practices reinforced in my mind that I shall now apply to my Fusions as originally built and expect to get even better results than before. This will largely be room position and treatment followed by EQ on the bass.
What did I learn?
1. A well designed speaker using good components like the Fusion is at quite a good level of capability and performance and my amateur efforts would take a long time or a lot of luck to replicate that, it’s a complex business, but good fun!
2. I did like something about the spacious presentation of the OB experiment, but that’s not to denigrate the Fusion as that doesn’t sound boxy anyway, someone somewhere said “only bad boxes sound boxy”
3. One thing I sought was “the magic”, like Linkwitz describes it, particularly the experience of multi positional listening without losing the image/sweet spot - whilst I got a reasonable band in the centre of the room I think I would have to go a long way deeper down a well thought out and optimised OB to achieve what he describes. That is not really a surprise as he was acknowledged as an expert in this field and I am not!
4. Details matter, and there are lots of them, from understanding the room and its interaction through speaker construction and set up to room treatment and finally EQ, there are stages to follow through and I learnt a bit about that process which was good.
5. I expect someone has already described that route very well, but I only started to realise what it might be when half way along it at least, anyone new to DIY audio, it’s well worth understanding more about it first, however for my mentality one needs to get the interest level up first and that means some experiments, dead ends and mistakes en route.
6. Many things inter-relate, to a much greater extent than I realised, for example when the upper bass/lower mid was light in the speaker output I heard what I thought was new treble detail, actually it was all about the balance, so the bass can easily affect your perception of other frequencies, obvious to those who know I am sure………..
7. As confirmation, I have now reassembled but not optimised the Fusions and all that detail is there, I completely mis interpreted the additional detail because the upper bass I was used to was not there……..
8. With many inter-relating factors one can work away at one thing to no avail when another, possibly less obvious might do the trick.
9. There were lots of useful responses to my question, some responses seemed to hit the spot better than others, that again could be my perception, it’s all quite subjective
10. It was fun! – thanks to all respondents and participants. – I shall now spend some time better optimising my boxes in their room before considering further experimentation.
A friend is hoping to build a OB using 2X 15 inch speakers per channel; with the following specs; fs33.6, vas10ft 3, qts 0.725, %1.26, 93Db, BL15-2tm, mass161g. Can anyone recommend a suitable mid- range and tweeter, suitable crossover?
Thanks
Thanks
No, too many unknown factors. Baffle size, budget etc
For crossover you need to measure and experiment.
Otherwise try to find a kit.
For crossover you need to measure and experiment.
Otherwise try to find a kit.