crossover frequencies

Paul brewin

Active Member
can anyone give me advice on crossover frequencies on monitor audio bronze 2 front b2 centre ,back are bronze fx ,yamaha rx_a870 ,it sets them at 40hz ,is this to low ,and would this av reciever be better patnered with more expensive speakers,say monitor audio bronze 6 at the fronts,room size is 12ft*15ft i know this is alot,please give advice on anything ,as im new to all this
 

dante01

Distinguished Member
It is recommended that you set all speakers as being SMALL irrespective of their physical size or frequency handling abilities. It is also suggested you set crossovers no lower than 80Hz even if the speakers are rated to be able to handle lower frequencies. The reasoning behind this is typified here:

Small vs. Large
Do you have a subwoofer in your system? Great. Then your speakers are small. Before you get all upset, read on. This is one of those audio myths whose time has come to be busted. To understand why, we need to talk about Bass Management.

In the early days of home theater it was thought that in order to reproduce the full movie surround experience at home it was necessary to place 5 large loudspeakers in the room. The reason for the size was the woofers. To play at theatrical reference levels and reproduce the deepest bass available in the content requires each speaker to have 12” or larger woofers. Let’s just say that this theory didn’t get very far in the real world.

A better and more practical approach came after studying human perception. The mechanisms that we use to determine the direction of arrival of sound depend on the frequency. At high frequencies the wavelength of sound is small and so sound coming from the side is shadowed by our head. That creates a level difference between the sound reaching the ear closest to the source and the ear on the other side. Our brain analyzes these level differences and produces an estimate of where the sound is coming from. But at lower frequencies, the wavelength of sound gets longer and our head is not large enough to produce a level difference at the two ears. Instead, we analyze the difference in time of arrival of sound at the two ears. Sound arrives first at the closest ear and we use that to determine the direction. But even that ability fails us below about 80 Hz. The wavelengths get very large and it was found in listening tests that 80 Hz is the frequency below which most people can not localize the direction of sound.

Taking advantage of this apparent “deficiency” in our hearing was what made home theater practical for millions of homes. Five satellite speakers of reasonable size could now be used because they no longer required large woofers. A subwoofer (or two) can reproduce the lower octaves and it can be placed out of sight since its content is not directional.

But there is also a practical advantage: directing the bass to a dedicated subwoofer channel with its own amplifier greatly improves the headroom in the main channels. The idea behind this was proposed in a Society of Motion Picture Engineers (SMPTE) meeting in 1987. The participants could not agree on the minimum number of channels required for surround sound on film. Various numbers were being shouted out until a voice was heard from the back: “We need 5.1”. Everyone’s head turned around to look at Tom Holman. He proceeded to explain what he meant: Take the low frequency content from all 5 channels and redirect it away from the satellite speakers to the subwoofer. If we do the math, then the content below 80 Hz is 0.004 of the audible 20,000 Hz bandwidth. But 5.004 didn’t sound as catchy so Tom rounded up to 5.1. By the way, don’t make the amateur mistake of calling it 5 dot 1. It is a decimal: 5 point 1.
Fast forward to the early 90s when the first DSP powered home theater receivers started to appear. Along with progress came complexity. Some industry forces believed that Bass Management should be an option that could be turned on and off by the consumer. That’s not necessarily a bad idea, but to make an informed decision requires much more knowledge about the system than what was available to the typical consumer. So, the Large and Small rule of thumb was established. The idea was to look at the size of your speakers and decide whether their woofers were “large enough” to reproduce the lowest octaves at the required levels. It was a noble thought, but looking at it 15 years later I believe that it has led to nothing but massive confusion. The poor consumer was led to believe that Large is somehow a good thing and was then left wondering why there was nothing coming out of their subwoofer.

Redirecting the bass to the subwoofer relieves the receiver amplifiers from having to work on reproducing the low frequencies and this greatly improves the headroom. If you happen to be using Audyssey MultEQ for room correction, you will achieve much better low frequency performance because the MultEQ subwoofer filters have 8x higher resolution than the filters in the other channels.

Here is a better rule: All speakers are Small. In today’s complicated AVR lingo that just means: If you have a subwoofer you should always turn bass management on. Always. Even if your receiver clings to the past and automatically sets your speakers to Large.


There is some room for improvement as far as the speakers are concerned, but I'm using MA Bronze (BX) with a higher tier receiver than the one you've mentioned without adverse results.

There'd be no real advantage to using the Bronze 6 speakers over the smaller cabinets you are already using. The lower frequencies are being directed to your sub so the lower frequency handling abilities of the floorstanders would be of little if any benefit to you. The drives units associated with the upper frequencies are the same on both the Bronze 6 and the Bronze 2 speakers. Floorstanders are also more demanding when it comes to placement and they do not behave well in smaller rooms or if in close proximity to walls and or furnishings.

Rule of thumb suggests that you spend at least double the recommended retail price of a receiver on a 5.1 speaker setup to be used with it. The upper limit would be 3 times the cost of the receiver. Spend more than this and it is suggested that you are spending more than is required to get the optimum performance from that receiver.
 
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Paul brewin

Active Member
My subwoofer is wharfedale diamond sw150, any advice on upgrade for fronts and subwoofers, looked at 2* monitor audio w10, subs, and monitor audio silver 100, for front, or any consideration would be good
 

dante01

Distinguished Member
Maybe look at the BK P12-300SB or the XXLS400 as being better and more affordable subwoofer options:
Sub Woofers - Sub Bass - Subwoofer

The sub doesn't need to be the same make as your other speakers.

Maybe also consider something like Monitor Audio Apex speakers plus the proprietary stands for the front. THey also do a matching center within the Apex range or you can use another A10 speaker for the centre:

Apex | Hi-Fi Speakers | Monitor Audio

The Q Acoustics Concept range is also worth consideration. THese are excellent speakers at a very affordable price. Again, buy the proprietory stands if going with the Concept 20 bookcase cabinets. These speakers are built using a very special anti resonance construction which is negated if you don't use the proprietary stands to mount them on.
 
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Rambles

Distinguished Member
My amp cost £1000,so looks like I'm going to have to spend £2000-£3000. On a 5.1system
What AVR do you have and what is it that you are not happy with in your current system?
 

Paul brewin

Active Member
Yamaha RX-A870 7.2,, I upgraded from, yamaha rx-v775, and q acoustics 2020i, still have wharfedale diamond sw150 sub,. I thought I was going to get so much more, I'm OK to spend £650. On fronts and back, and 2*subs, about £1000, but will me spending another £2500 get me an amazing sound
 

Paul brewin

Active Member
The week link, I think is the subs, which I don't have a clue about, up what upgrade path for them. I thought it was better to keep the sub same make as the speaker company
 

Rambles

Distinguished Member
Okay. One step at a time!

There are a number of things that you might be able to do to improve the sound, without having to spend £2k to £3k on speakers.

Your amp and speakers are decent, so they should sound sound reasonable. Your subwoofer may be the weak link, but even so, it shouldn't sound awful.

What is your room like, and how have you got everything positioned. Do you want to post up a few pictures and see if we can advise on positioning tweaks that might help with the sound?

What are you listening to on the system, eg blu rays, tv, music? Does it all sound disappointing, or do some things sound better than others?
 

Rambles

Distinguished Member
4k Blu-ray sounds amazing, music average, room is 12ft x 15ft,
Good job, the room looks great!

The 5 main speakers look very well positioned, maybe the sub would sound better if it wasn't in the corner, or if it has to go in the corner you could try it pointing in different directions to see if that helps. Are you eq'ing it with your AVR, and does your AVR give you any of the curve details?

Replacing the subwoofer won't help if it is the room or the placement that is causing the problems. You can get anti-modes that are separate equalisers just for subs, or even isolation platforms that might help. I am not an expert on subs, so maybe someone else will come along to advise a bit more on that, or you could ask in the separate subwoofer forums.

Now the fact that 4K Blu Ray sounds amazing is excellent news :) I think that means that your system is functioning well, when it is being fed a good high quality source.

With regard to music not sounding so good, I am afraid that is usual for AVR's. There are a plethora of threads on here with people saying the same thing. And the best way to improve that is to use a separate integrated amplifier for music. You can connect it to your AVR via the front pre-outs, and if you use an integrated amp that has a HT bypass function, it will act as a power amp in that mode, so will give your AVR a bit of a boost at the same time.

Your front speakers will be connected to the integrated amplifier, and you use that as a stand alone amp for music purposes, connecting your music sources directly to the integrated amp. The AVR remains switched off. Then when using your AVR, you have the integrated amp powering the front left and right speakers, so the AVR then powers the other three.
 

gibbsy

Moderator
Room looks good positional wise. As Rambles says poor music performance may come down to the AVR and possibly the source. The centre is, to me, a little too low. Could you angle it more upwards using isolation pads? Sub again as Rambles said could be improved by better positioning away from the corner. If that is not possible then perhaps of the RELs, T5i or T7i may be better as these are engineered to perform in a corner.
 

stewjoy

Well-known Member
I agree with what’s been said ,only difference is I have a bk xls 400 and that’s in the corner but I use an antimode and I think it’s brilliant, maybe look at that situation .
 

mindforge

Active Member
Room looks good positional wise. As Rambles says poor music performance may come down to the AVR and possibly the source. The centre is, to me, a little too low. Could you angle it more upwards using isolation pads? Sub again as Rambles said could be improved by better positioning away from the corner. If that is not possible then perhaps of the RELs, T5i or T7i may be better as these are engineered to perform in a corner.
Any tips for where to get isolation pads for to angle upwards? The tallest centre speaker stand j could find was 600mm and that's about 200mm off ear level.
 

gibbsy

Moderator
Any tips for where to get isolation pads for to angle upwards? The tallest centre speaker stand j could find was 600mm and that's about 200mm off ear level.
I think @Rambles uses, or has used some. My cabinet mounted centre has the tweeter at 750mm high so I just use 8mm Fisual isolation feet. Also make sure the front of the centre is proud of the shelf edge to avoid reflection. Can't quite tell from the photo so apologies if it is.
Fisual Round Adhesive Isolation Pads Pack of 4 - System Tweaks - AudioVisual Online - UK Home Cinema and Hifi Specialists
 

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