Loudspeaker angle

I'm curious about how people in this forum angle their loudspeakers. In music circles, the majority of people these days are using so-called near-field monitors, positioned close to the sound engineer. These were initially chosen for economic reasons and to better match home systems, but it's become more of a standard. It's generally recommended that these be angled with the axis of the loudspeaker pointing directly at the head of the listener - and in a stereo set up, the listener and the two speakers should form an equilateral triangle. As I understand it, on-axis placement is used because most loudspeakers (near-field monitors at least) give a flatter frequency response when positioned this way rather than off-axis - so the engineer is less likely to swayed in his/her mixing decisions by any change in tone colour introduced by an off-axis placement.

I have a home studio with a pair of "mid-field" Tannoy System 12 DMT II monitors. In the manual for these, it's recommended that the speakers be placed between 2 and 4m apart and that the "distance between the monitoring position and each speaker should be slightly greater than the distance between the speakers". In the case of these speakers it's also recommended that they are angled between 10 to 15 degrees off-axis to give "the optimum spread of HF information" - which I assume means: to get the high frequency part of the spectrum is at its flattest.

I wonder though that there's not also the question of the scale of the sweet spot at play. Near-field monitors are better suited to a single listener, whereas mid-field and far-field monitors give a bit more space to squeeze in a few smelly musicians around the engineer. Perhaps too, an off-axis speaker angle helps to reduce cross-talk (between ears), or at least stops the possibility of an inversion of the stereo image by not allowing the channels to cross paths within the confines of the room.

OK - so in the audiophile/hi-fi world, what do people do? I've often heard people recommending parallel speaker placement or with a "shoe-in" angle adjustment. What's the reasoning behind this? It'd be interesting to hear what people here get up to.

Cheers,

Iain

 

I have a pair of tannoy definition 700 monitors my room is 16 feet wide and the speakers are placed 3 foot 6 inch from the back wall an 2 foot 6 inch from the side walls the room is twenty five foot long and my seat is fifteen foot from the centre of speakers the speakers are angled so that they would cross roughly 4 foot in front of me and they sound divine loads of headroom and big soundstage but it took a bit of experimenting till I settled with this position very happy with it all

 

My UK listening room is very square, about 4.7M x 4.7M, and has the system in one corner. I have the ATC-SCM19's very slightly toed-in, probably less than 5º each. That seems to give me quite a wide listening area, about 2 metres wide, some three metres away from the speakers. In France I have a far bigger listening room which is the main open plan living area and has maximum dimensions of around 15M x 9M, is a weird shape with sunken centre, curved walls, recesses etc (think early Ernst Blofeld/Bond style). The system all sits in a slight recess and from experimentation, I have found to get the best image, testing using XLO test CD's, I need to toe-in the ATC-SCM40's by around 15º each. The conclusion I come to is that it is so individual, dependant on the speaker design and the room shape, that there are no hard and fast rules. I can recommend setting levels carefully using an XLO test disc and AC voltmeter and only then tailor to the room. Also use the in-phase test tracks to check phasing and stereo image coherence.

Wilson

 

Thanks for the tip on the XLO disk, I managed to locate a copy, very handy setting the channel balance. Trying it out on my jbl 4312As, the "demagnetising fade" revealed a buzz in the right channel, either in the cabinet or in the main driver which I'd never noticed befor (it's possible to atenuate the two tweeters, I believe completely, with two pots on the front of each unit). Oh well. Does anyone know the purpose of that particular test? Cheers

 

The only things I could imagine the demagnetising fade track as being used for are if you copied it to a tape and then ran it through either your reel to reel or cassette deck. I cannot imagine it however, being anything like as effective as the proper mains powered demagnetiser I use on my Nakamichi BX-2 deck. The only other thing I wonder if the demagnetising track could be for, is to get rid of any residual magnetism in the output transformer of a valve amp.

I only realised I had been using a tape head demagnetiser wrong for the last 50+ years when the man who serviced my Nakamichi showed me the correct way. I had always just waved it backwards and forwards over each head. You should position it near the head or if it is plastic coated like mine, on the head, switch it on and then move it away at the speed of an arthritic snail immersed in toffee to at least a metre away. Then repeat with second or third heads.

 

Thanks, I had a Revox A77 years ago that was too heavy to bring over here unfortunately. I vaguely remember something about demagnetising the heads, but never did it myself. I meant to ask what you use the AC meter for. Do you put this across the speaker terminals running one of the sine wave tracks on the CD? To correct balance? That would be interesting. Doing it by ear, my hifi system (with the JBLs) was weighted towards the right and it's a shame the Quad 34's balance control is so hard to adjust/reposition. Does anyone know if there's an internal trim pot to calibrate "zero" balance on the Quad 34 (again, zero is hard to find/see on the 34)?

 

Surdo,

The AC meter is indeed to set base level between channels. The funny thing is that your ears will not agree with the meter because they have not been equalised In my case after close to 50 years of motor racing and rifle shooting, my right ear is nothing like as good as my left.

On the Quad 34, when did you last have it serviced? The service people should equalise the gain between channels but having had a look at the circuit diagram in my Quad book, I cannot see a trimming pot other than the main balance control. From when I had a 34 some years ago, I remember it being quite easy to change with a lever concentric with the main gain control. If it is a long time since you had it serviced, it will be inevitable that the old IC's will have drifted and the gain between channels will be different plus the capacitors will have deteriorated to differing extents.

Quad service is getting difficult in the UK. Quad themselves are nothing like as good as they used to be and made a total mess of the last thing I had serviced by them. Net Audio has changed hands after the death of the original owner and I fear Fidele in Scotland, who I think were best of all, are gone (their website has disappeared). There is still CPT Acoustics in the UK, where Colin Toogood is a nice guy and 100% honest and competent.

Wilson

 

Yes, i have a bit of dip in the frequency response of my left ear (at 8kHz if i remember correctly) which I blame on violin lessons as a child. I'm curious to try out the AC meter, will do that this evening. The volume control on the 34 is a rotary switch so it's nice and easy to recall volume settings by feel. Perhaps the pan lever had a "click" to it once upon a time when in the centre position, but it doesn't have any more and the amp is positioned practically on the ground so it's hard adjust by sight without lying down - i should do something about that. The servicing situation is pretty dire here - i'll only risk a service if and when something breaks! Cheers

 

In a recording studio they are not looking for the niceties of space and ambiance but more the balance and they type of sound they wish to create .. as such the speakers are usually on each side of the mixing desk and pointed direct to the ear to avoid any reflected sounds .. but also at bigger studios a larger pair of monitors may also be present at the back of the mixing room in each corner .. not sure what for as I am not a recording engineer but when i played in bands some years ago in the recording studio the little ones were used for the mix down and the final product was listened to on the big boys after all the mixing was done.

In a nutshell - experiment with toe in on your loudspeakers and whichever position sounds best to you is the position to keep em at ....