Testing, testing.

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Thanks to Vic and Parla and

Thanks to Vic and Parla and best wishes to everyone!

VicJayL wrote:

VicJayL wrote:

I had occasion to refer back to Angus Watson's "Beethoven's Chamber Music" recently, and saw the complete works listed by opus numbers at the back.  Being the obsessive that I am I thought I would seek out recommended recordings of each in order and call them up on Qobuz.  A project on the side, as it were.  I am amazed at what a rich experience it is turning out to be.  It should keep me out of mischief in 2018 anyway.

 

Best wishes one and all.

Enjoy - a good project for the new year.

congratulations and best wishes.

Congratulations and best wishes indeed. To come back to Vick's experiences with Qobuz, I finally jumped onto that bandwagon, and mostly do not regret. Sound quality is very good indeed, particularly on my main system. Harnoncourt's interpretation of the Bach Weihnachtsoratorium sounded just perfect, and on Qobuz it was far better than the vinyl version that I own myself.

The Qobuz Chromecast app used with the main system is a bit of a pain, and certainly needs some work. The web browser version that I use with my desktop system is far better.

Willem

Good to see you are still

Good to see you are still around, Willem......

A quick question while you are here - can small speakers sometimes be better than larger ones? I recently had to move some things around - mainly for the Christmas tree - and ended up swapping speakers from one room to the next. My Wharfedale Diamond 9.0s have now been hitched to my main amp (100 watt Cambridge audio) in the largest room. The bigger speakers (121s) have now moved into the smaller room (dining room) and hitched to the old Denon UDM30.

Anyway - the upshot is that the smaller speakers in the big room, while they don't have much weight or bass, seem to be more revealing than the bigger ones. Old familiar songs come out sounding crisper and more detailed, and voices, in particular, seem to be more vivid. Could it be that the 9s are just better than the 121s, though inferior in certain obvious respects? Or could it be that the bass of the 121s, thumping about the room, ended up obscuring the details? Or could it be just a temporary auditory illusion.......?

The 121s in the small room, incidentally, are practically unusable. The sound is unpleasantly hard and boomy - hardly worth bothering with.

(I may be going off the 121s.............)

speakers too big for small rooms?

Jane, you may be right: speakers can be too big for the room they are in. You may indeed suffer from one or both of the following problems.

First, in small rooms you are likely to position them relatively close to walls or even into corners, and this boosts the bass. Speakers should have their tweeters at ear height, and not be on a table or shelve, at least some 50 cm away from rear or side walls, and not be right in the corner. The reason really is quite simple. Lower frequencies are omdirectional, unlike the higher ones. Put a speaker on a pole in the open air (in free field), and a lot of bass energy will leak away to the rear. Put them on the floor in the corner of a room, and all that energy will be focussed into a much smaller angle. You can do the experiment. Put a speaker right in the corner of a room, and on the floor. Then slowly pull it out, into the room, and place it on a stand. The differences will be enormous. So a speaker designer always has to decide on the typical position his speakers will be in to have the desired balance between high and low frequencies. If you think the speakers sound too boomy, move them further away from the walls. Of course, that is where it gets difficult in a small room.

Second, rooms suffer from room modes. These are resonant peaks and dips at the resonant frequencies of the room's dimensions, and they are responsible for that boomy one note bass. Typically, they occur below the so called Schroeder frequency of a room, usually between about 100-200 Hz (the lower, the larger the room). See here for a calculator: http://www.mh-audio.nl/sg.asp So in a small room, the room modes will occur at higher frequencies, and will be more obnoxious to the ear. In addition, room modes also have their upper harmonics, smearing the sound at rather higher frequencies. Whereas resonant peaks above the Schroeder frequency can be dealt with by using damping materials such as rugs, curtains etc, this will not work below the Schroeder frequency. For that you would need pretty massive bass traps, which is, of course, not really feasible in a small domestic room.

So the first thing to be avoided is to use speakers that are too large for a given room. If there is no bass that can excite room modes, there is no problem to be cured. In your case, I don't think the 121 is too large for a more or less normal domestic room (how large/small are the rooms you are talking about?). It was obviously designed with smallish British room in mind. In my own case it is precisely for this reason that in my study I use the Harbeth P3ESR, and not one of their larger models.

So what can you do? If you really want to diagnose the problem you will have to do some measurements. You will need a relatively cheap calibrated microphone

like the UMIK-1 usb microphone. Connect it to your PC, and install the free REW software package. The software is not particularly user friendly, but that is because it has so many options. There are plenty of YouTube tutorials, and they also have a friendly user forum. What I can predict is that the graph that it will produce will show horrifying peaks and dips anywhere below perhaps 200 Hz. And if your speakers are indeed too close to the walls, it will also show a rising response in the lower frequencies.  The take home message is that in-room response is perhaps the most pressing problem in any audio setup.

So what can you do to addres such issues? The first is obviously to pull your speakers further into the room. With less bass, there is less to go wrong. You can compare the result by measuring again, but even without measuring kit you will hear the difference. However, there will be domestic constraints on where you can locate the speakers, and this is where good old tone controls come in. Assuming your reciever has them, just turn down the bass a bit. If it does not, and assuming you are using the Chromecast Audio, this now also has its software equalizer that sports classic bass and treble controls (look under settings). If you are using a computer as a source, it may have some sort of audio equalizer in its audio settings. If not, just install the free Equalizer Apo software that will do this, and much more. But be careful not to choose some baseline setting that is anything other than flat/neutral.

If you still want to go beyond this you will really need to measure the current response with REW. REW can then calculate a correction curve to compensate for the peaks (and to some extent, but please not by much) for the dips. It will very carefully and precisely reduce output at the peaks, and just the peaks, to arrive at a far flatter response. I had to do that in my study. My little Harbeths still had a bit of a bass boom, even after I had lifted them off the desk with short stands to get the tweeters at ear height. I measured the response and there were some undesirable bass peaks. REW calcuted the correction curve, and I downloaded that into the Equalizer Apo on my desktop computer (my only audio source in that room). This fixed the problem. In this situation, the only expense was the measurement microphone.

But what if you use more than just a computer as a source? How can you apply such a correction curve? Of your amplifier has a separate pre amp output, power amp input connection you can insert a miniDSP, a little and not that expensive unit that will do the equalization for you, using the correction graph from REW. Unfortunately you will be spending yet more money, after you already bought the microphone.

So in your case, I would begin by keeping it simple and do things by ear. But first of all, my question would be about the size of the rooms we are talking about, and the location of the speakers. I do think the 121's are the better speakers, and not just because they have more bass. And I do think they should be fine in most UK sitting rooms. Keep them at least 50 cm away from walls, on stands (tricky with crawling kids, however), and maybe turn down the bass a bit.

I hope this helps a bit- time for experiments.

Willem

Thanks Willem - very helpful.

Thanks Willem - very helpful.

Judging by what you have said, I think I have  grossly underestimated the importance of speaker placement. The 121s in about the worst place in the larger room - much too close to the wall, and also  in a corner........Moving them for the time being is not really possible, however. I am currently in my mum's house and have very limited control over the environment. Move a curtain an inch and she is instantly up on a chair, twitching them back into place. There is also the baby situation.......The corner, protected by a barricade, is the only safe place for the moment. (The larger room is a decent size - about 30 sq metres)

Hopefully, I will be moving out in the next few months and will be able to put the speakers just where they can sound best. I will look into stands or something of that nature. In the meantime, I will experiment with turning the bass down a bit.......

Thanks again. 

Also, if this is relevant,

Also, if this is relevant, there are a lot of smooth hard surfaces in both rooms. Hard oak floors, bare walls, stone fireplaces etc

hard surfaces

Hard surfaces will be responsible for the shouty sound, i.e. resonances at higher frequencies. Only damping will cure this. We have a modern minimalist interior, and it is hard to get that right.

Willem

sound quality

After reading the above, I moved my speakers away from the wall and detected not the slightest difference. Willem has often stressed the limitations of human hearing but has not explained why his own is apparently omniscient. In particular as regards LP v CD. I've no axe to grind myself, as I haven't listened to LPs since my turntable gave up the ghost about 25 years ago. But I know people who swear that LPs often give much better sound than CDs, one of whom happens to be a professional conductor. So it would seem that sound is as much a subjective quality as is musical taste.

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