Another post link directed me to sound doctor. Some interesting ideas and advice. So I used bungs for my large floorstanders. Back to 80hz, SMALL crossovwr. Interesting experiment!
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No replies eh? Not surprised really. However. Listening to Dire Straits right now. Placebo? Maybe but heres my opinion. Probably due to room interaction, size etc. Who knows but it was free....
Separation seems cleaner. Vocals more focussed. Bass tighter but extended. I'm lovin it right now. Cost 0. Value 100. Will go back to the 'doctor' to see what else he has to say.
Cheers. The snow clearance can wait
I've been pushing this for years! :grin:
They're basically THX suggestions.
David @Frank Harvey Hi-Fi, Coventry
Thanks David. I know yr crossover advice and have taken it. Didnt know you banged on about bungs tho. I thought it would ruin the sound that manufacturer designed into its speaker but it just seems to let the mid & highs sing and integrates more smoothly with the sub. Cheers
More to do with the 80Hz crossover point and setting everything to small, regardless of the size of the speakers. It's not for everyone though.
Using bungs on speakers does make them sound more like a sealed box, which is more like a dedicated AV speaker - there's still fundamental differences, but its as near as a hi-fi speaker will get to sounding anything like it should do for AV. The problem is it usually screws up the music performance. Generally, I don't tend to recommend using bungs as it does tend to vastly change what the manufacturer was aiming for, and can really suck the life out of a speaker. Manufacturers will choose specific drivers for use in a sealed cabinet, and also for a ported cabinet - swap the two over and they don't work so well.
It's a case of suck it and see really. Try full bungs, give yourself time to adjust to the new sound, but if the speaker then sounds dull and flat, try making your own bungs and making a hole in the centre of the bung - the more you take out, the more air is allowed to pass through, and the less the intended sonic signature changes.
The other thing to note is that fully bunging a speaker deadens the overall sound. This is fine for higher listening levels, but lower levels will sound a little lacklustre. A partial bung would work better in this case, but not too many people want to swap and change bungs depending what they're watching and how loud they're watching it, so its a case of finding the happy medium.
Thanks David. If nothing else it suggests that experimentation can be really useful and no size fits all. I was most surprised about music performance thinking it may suffer. I rhink it has led to better integration. Maybe my large speakers were producing to much bass at some frequency above the 80hz crossover. Whatever the reason I will settle into the modified sound and no doubt continue to experiment. Cheers
Generally speaking, speaker manufacturers use ported speaker designs to obtain greater low frequency extension / output from a speaker. This is achieved by the summation of the low frequency driver output and the port output. The inherent problems you have with this type of speaker design are that there is a differing phase relationship between the port and the low frequency driver, which can lead to out of phase relationships and smearing through the low frequency range. Then when you add a subwoofer to a ported speaker system it has its own phase relationship. Know you have 3 sources of low frequency energy with differing phase relationships. By port bunging the speakers you remove the out phase relationship of the port, know leaving only 2 sources of low frequency energy with differing phase, the subwoofer and the speaker low frequency driver. Know by careful setup the subwoofer and speaker low frequency driver phase can be phase time aligned at a selected crossover frequency as there are only two differing phase sources. This leads to seamless integration between the sub and speakers. There are more details on how to do this in Barry’s whitepapers.
Furthermore, by setting the speakers to small and the crossover to 80 Hz, the bass managed bass redirects all low frequencies below 80 Hz to the subwoofer. This has a number of benefits. Your amplifier and speakers are know not having to produce any low frequencies below 80 Hz, thus resulting in the greater reserves for the amplifier to produce the remaining frequencies and the drivers to focus on 80 Hz and above frequencies. This results in cleaner reproduction of the 80hz and above frequency range produced by the speakers and a overall improvement in the low bass output, know produced by the subwoofer.
Generally, you will find a speaker position in a room, which give you the optimum mid-range and upper range performance but this position does not give the optimum low frequency performance. You then often find users moving speakers closer to the room boundary to increase bass performance from room boundary gain. By adding a subwoofer you can know place the speakers in the optimum position for mid-range and upper range performance whilst placing the subwoofer in a position that gives you optimum low bass performance (flat response). This also improves the overall performance of a system.
Barry’s knowledge is phenomenal and his white papers are exceptional.
Hope this helps.
Manny @ AV Tech Solutions Ltd - UK & Ireland Distributor of JL Audio Home Products
All that sounds about right thanks. Lost the link
Brilliant and very informative,great find Robin .Iv'e only had time to flick thru but i think the doc is gonna be best mate!
Speaker placement for me is a problem at home...looking forward to reading more
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did you also try changing the distances for the fronts & sub to try and balance out the phase relationship?! Interesting learning about the way that AV recievers act in reverse in this regard & how changing phase on the sub on only adds delay.
I was looking at one of the active crossovers from Behringer that allows you to add delay to the fronts but ended up going with a second hand Bryston. Just waiting on some leads now before I can get it plugged in.
I'm still not entirely sold on the 80hz crossover thing. I can understand that smaller speakers might benefit, but I can't see the problem with sending full range signal to larger floor standers that can handle this. The guy that I bought my Yamaha from also had the same model & he swore that crossing over at 80 & setting to small was the way to go.
The front speakers that I have now are front ported, but the port is more like a thin slot rather that your traditional circle. My old floor standers that I had before these were rear ported & were situated quite close to the wall. I lifted them up and spiked them to a piece of sandstone & then made up some foam bungs. The difference was startling, tightedned everything right up, much less boomy.
I loved the bit in the animated video where the guy tells his wife that he is adding subs because he is the KING!!! tried that but it didn't go down that well
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Thankx neuphonix. My sub phase is variable but not yet experimented. If nothing else these discussions give us ideas to inform experimentation. No one size fits all but in some rooms, some small changes can yield big gains. Conversly, a 'bad' room will never improve by throwing money at new kit.
Unfortunately I am pretty limited in my placement options, not the biggest of rooms. So I've built the two subs into my stand beneath the centre.
The idea was that they would be best placed as close to the fronts as possible. I did toy with the idea of taking the speakers off their stands and placing them on top of the subs. But the stands for the Diablos are just such a statement, & I had reservations about the vibration from the subs.
If I ever move to a bigger place I will be able to start with the crawl test. Might give it a go this weekend, it would be interesting to know where the ideal place would be even if I cant use it.
I do have the receiver set to 80hz now that I have stand mounts, but I remember with my old speakers that large was the way to go. There was a mixed feeling with movies after I made the change, wondering if I'd done the right thing. My new F112 has gone some way to putting those demons to rest
The 80Hz crossover point is a THX requirement (as is sealed speakers). The interaction between smaller, sealed speakers and the room boundary greatly reduce the possibility of the overall sound changing drastically when used in different rooms, so when the soundtrack is mixed on small, sub/sat speakers in the studio, you can then play that soundtrack on a small sub/sat speaker system in any number of rooms and what you hear will be far closer to what was originally mixed.
Also, by removing the need for any sized speaker to reproduce anything below 80Hz eases its workload so the frequencies it does produce can be produced more cleanly, resulting in better quality.
Sealed subs blend better with sealed boxes. Ported subs tend to work better with big floorstanding speakers as ported subs tend to offer clean output low down, but aren't as good with higher notes, which in this case can be dealt with by larger speakers. I feel there is still a benefit to using large speakers with an 80Hz crossover point as it removes output well away from the troublesome port frequencies. If the speaker package is made up of small and large speakers, it brings the operating range of all of the speakers within the same bandwidth - 80Hz and above. This gives a more consistent soundfield as all the speakers are doing the same thing. And of course, leaves the sub to do the hard stuff.
Of course, this isn't for everyone. Some like the warmer sound that their big floorstanders will give them.
I find that vocals (especially deeper mens voices) lose depth and therefore presence / realism with the centre set to 80hz. I much prefer a 70hz cut off.
Maybe my MA RSW12 sub isn't good enough at reproducing detail at 80hz.
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hi,thanks kn advance. suppose i find my floor standers sound better when fully bunged and say iliked the sound verymuch and want use my speakers always bunged say years together. will there be any chance of damaging thespeakers.
Most modern loudspeakers will have no issue port bunging the speakers, although there are circumstances when I would not do so. One such instance is when it is clearly stated in the loudspeaker manual to not port bung, thus voiding warranty. There are some speaker manufacturers that supply port bungs with some of their loudspeakers, such as B&W, which is excellent. If you are unsure of your particular loudspeaker I would contact their technical support and ask them.
Hope this helps.
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