Hello Didier,

Thanks again for your help. I do have Audacity and could try those adjustment. I have taken note of what you have said i.e. re keeping the same level when comparing, and will do some more experimenting and send another attachment soon. Hope you don't mind listening to another sound file and commenting.

I don't know whether a rug on the wall behind the piano and something on the ceiling above the piano will help. I could try it, and also something in the nearest two corners of the room. The piano is about six inches away from the wall. The piano tuner said that the piano is in about the best place acoustically in the room.

Does the angle that the microphone is on even make a slight difference? I read the instruction manual yesterday about the microphone, and it said to address microphone from the side (not the top of the grill) above the SP logo badge, so I have been doing this.

Hello Didier,

I have just recorded another piece today as it was a cool afternoon. I have included just the first part of the piece for you to have a listen to. Am sorry it cuts off rather suddenly.

Yes, it should make more than a slight difference! I understand now why your recording sounds so far.

As soon as I heard the first notes of your last recording, I thought 'great!'.
That is a pity that there are stlll these disturbing noises (produced by the action or your nails ?).

Anyway, using only one microphone seems being less a limitation than what I was anticipating. You could still improve your sound using some kind of advanced audio editing (not at all needed for sharing music with us). For example:

However for acoustic recording, especially with a "pressure gradient" mic like the SP1, the proximity effect continues noticeably because bass boost continues to decrease proportionately as the distance increases until about 6ft. Bring18, do a bassy test recording by placing your mic at 1.5ft and at 8ft. You will get different bass responses at each of those distances.

This proximity phenomena does not happen with "true pressure" omnidirectional mics and they are immune to proximity effects and that's why they are popular for classical piano recordings like the DPA 4006, Schoeps MK2, Sennheiser MKH8020, Earthworks QTC, Avenson STO-2, etc. You get a much more flatter frequency response. But, you can't use them to their potential in an untreated room.



To get a quality recording, you have to acoustically treat the room. A rug will help for midrange and high frequencies, but will do nothing for the bass frequencies. Eliminate any nearby reflections going to the mic by placing broadband absorption panels - DIY fiberglass panels made from 2ftx4ft 2inch OC-703 and OC-705 covered with burlap - color of your choice to match the walls. The walls, corners, and ceiling closest to the mic position is where you want to start first. That's where the first reflections occur and they're harsh. After doing a lot of research online, and discovering the staggering cost to treat my entire room, I am doing this on my own without costly commercial panels. The results so far have been amazing! Better Bass definition, midrange clarity, highs are not harsh. I am not forced to mic in cardiod mode, and for the first time I can place my new omni Sennheiser MKH 8020 mics at a distance of 3-5ft from the curve of the piano and get a full and rich sound. If you're interested let me know if you want to make your own acoustic panels for the fraction of the cost of commercial panels. They're simple to make too...

Hi George,

I was not expecting that the proximity effect would be significant at so large distance. For its 40 series Audio Technica gives the frequency response of the directive microphone at 12" or more on axis, which seems indicate that the proximity effect is significant only below 12" (see for instance AT4050 Specification Sheet). I guess that this is not true for all mikes.


Congratulations! I would be much interested in some samples for comparing them with your 414s. Thanks in advance if you can do that!

Hello Didier,

Thanks for your comments once again. I would love to hear your playing. Where can I go to hear it? I heard the first part of 88man's playing; I think it was Chopin's Nocturne No. 20. It sounded very beautiful. I only had time to listen to it up to the first one or two trills and admired the clarity of the trilling let alone the sound of the whole playing. There's something in the saying that beautiful music makes time almost stand still.

I have found a very good handyman in town who could do those panels if I can't. He's done a marvellous job painting my garage, outside of house, pergola and fence. Plus he is quick. Can you give me any more information regarding the panels and approximate cost. An Australian dollar is worth about 80% of an American dollar.

I am not good at analysing extraneous sounds. For instance I thought my pedal was making a noise and it was, so I rang the tuner. However after I had spoken to him I went to the piano again and realised that the noise that I could hear the most was the noise of hammers returning when I played chords. I just clipped my finger nails a few days ago so it shouldn't be them.

Could you tell me what you did to edit the sound file? I think this forum is wonderful; here I have you helping me with your patience, and even to the extent of editing my sound file. I do have Cubase LE and Audacity 1.3.5. Can you tell me precisely what you did so that I may be able to go to the same file and practise it (the editing, what you did). Which software did you use to edit the file with?

How would you explain what you did when you edited the file, and the before and after result? I listened to mine again and your edited file and can't explain the difference, except that your edited file gives better clarity and has gotten rid of some sounds we don't want to hear.

Hi bring18,

I used a noise gate and a tube preamp simulator to edit your recording. I used the noise gate in Wavelab and the Preamp Emulator plugin. There is also a noise gate in Audacity (Effects/Noise elimination, I am not sure about the name because I have got the French version). I do not know whether Audacity accepts plugins.

I am registered as a pianist here. There are links to my recordings on my page.

Hi bring18,

I used a noise gate and a tube preamp simulator to edit your recording. I used the genuine noise gate of Wavelab and the Preamp Emulator plugin. There is also a noise gate in Audacity (Effects/Noise elimination, I am not sure about the name because I have got the French version). I do not know whether Audacity accepts plugins.

I am registered as a pianist here. There are links to my recordings on my page :

Cheers,

Didier

Hello Didier,

Just had a listen to the Prelude and Fugue no 16 Book 2 by Bach. I enjoyed your playing and it also gave me a chance to listen to the mp3 sound file. It was interesting reading about your life story with music. You didn't get started until a fairly late stage.

I am not sure by what you mean when you say that already my music is good enough to share with you.

Hi bring,

you should have done a mistake because I never played the Bach piece that you said...


You can access my most recent recording, which may be the one having the best sound despite (or because ?) I did not perform any audio editing, here

http://server3.pianosociety.com/new/phpBB2/viewtopic.php?t=1476&postdays=0&postorder=asc&start=15

The link is in my third post in this page.



I meant that music is more important than sound: it was an invitation to submit a complete recording in the Audition room.

I have been updating my first thread on "Making Professional Home Recordings" from time to time. I just added more pertinent information.

I should also point out that I have since I have made my own bass traps or acoustic absorption panels for the music room. It has helped tremendously to tame acoustic anomalies which plague most smaller spaces, such as room modes, flutter echo, ringing, and comb filtering. There is more clarity and bass definition; and less muddinesss and harsh peaks in the high notes. I have consequently changed my microphone polar pattern from wide cardiod to omnidirectional. It has given a more natural tonality to the instrument. If people are interested, I can post information on how to make your own acoustic absorbtion panels at fraction of the retail cost.

Enjoy Your Recordings!

Hi George,

I wonder whether I should go for some bass traps like you.
would you have some short recordings for comparison between before and after room treatment with the same microphones and same placement ?
Anyway, thank you for your advice,

Didier

BASS TRAPS - ACOUSTIC PANELS FOR THE HOME STUDIO

Hi, Didier. Any small to medium size room will benefit from bass traps/Acoustic Panels. The best thing to do is to walk around the room clap your hands and speak around the area of the piano, mics, and listening position. If you can hear flutter echo, ringing, room modes then it's worth treating with bass traps. If you have nasty resonances on certain notes, loss of definition or clarity in sound, then it's also worth treating with bass traps. It also depends on fixtures in the room, wall construction, geometry, dimensions, glass, piano/mic location, and nearby reflections.

For all practical purposes to record in the home environment, bass traps function to mainly absorb sound reflected by walls, room corners, and ceiling closest to the piano and mics. It also helps to reduce unwanted room modes, ringing, comb filtering, and flutter echo, which plague all small spaces in a typical home with 8-10ft ceilings. It also alters the frequency response of the room so that the peaks and nulls are flatter across the frequency spectrum.

The best way to treat any room is with bass traps that use fiberglass panels. I am not sure what you have in France, but I highly recommend Owings-Corning 703 (OC-703) or equivalent fiberglass panels that measure 2ftx4ft. You can also use Roxul Mineral Wool, Roxul Rockboard, or Knauf Acoustical Board which are all cheaper. However, their absorption coefficients are lower for bass frequencies, so you may have to double the thickness to get the same absorption of OC-703. They all measure 2in thick. Don't bother with foam panels that you see at music outlets - they much less effective than fiberglass because they have much lower absorption coefficients.

I made my panels 4in thick, by doubling two 2in thick 2ftx4ft OC-703 fiberglass panels. I glued and screwed together a 2ftx4ft frame out of 4.5in wide pine wood and placed the fiberglass panels inside (4in total thickness). To camouflage the panels in the room, I matched the color of the acoustic panels to the color of the walls by stapling an ivory colored burlap fabric over the entire front and sides of the panels. It looks great. To cover your construction, you must use very porous fabrics; I find that burlap is very cheap and effective. You can hang them on the walls like a picture frame with wire and hooks, or make an H-frame pedestal to place on the floors. The great thing about them is they're portable, I can take them down if guests are coming over. The entire project took me a weekend to make. Your local hardware store can easily cut the wood for you, so that all you have to do is glue,screw, and staple. If you can make a picture frame, you can make your own bass traps. Each bass trap cost me $60 including everything (glue, screws, staples, burlap, wood, OC-703, pedestal, shipping, and taxes). The retail cost for each bass trap would be $325 - $375 in the U.S. The entire room cost me around $300; Retail would have cost me at least $1750.

Amount of bass traps depend on room dimension, shape, and the location of piano in the room. Triangulate the nearby reflective surfaces from the piano source to the mics, and place the traps in the path of direct nearby reflections. Don't go crazy since you only need to treat the nearby reflections from the walls, corners, and ceiling that will interact with your mics. Don't worry about walls that are away from the mics. As you know, there are phase cancellations/summing, delays, etc. that can only hinder clarity and evenness of frequency response. By negating the majority of the nearby reflections going to the mics, you're picking almost an entirely direct sound from piano source to mic. You may even find yourself using true pressure omnis, like your Avenson STO-2, at a farther distance to 3-4ft and allowing the sound the "breath" and coelesce by the time it reaches the mics. Once you place the panels, you'll hear that the piano sounds more damped and not as loud as before, because you're limiting the reflections coming to your ear, and what you are hearing is the direct sound of the piano. Don't worry about the loss of "small" room ambiance, because you can always reverb on your DAW, without amplifying the anomalies that were there before treatment. You'll get a much clearer and more natural sounding reverb. Add only the panels that are necessary, you can add more if you need to, but address only the nearby reflections first - the walls and ceiling around you and the mics. If you find that the sound is too tight and damped, either move the panel(s) around or remove a panel and use the extra panel for your monitor speakers... Just like mic positions, you may find you have to move the bass traps around to for the best sound. For my room, I am using only 5 panels - 2 in the corners 4inx2ftx6ft, 2 rear wall 4inx2ftx4ft, 1 on ceiling above mics/piano 2inx2ftx4ft.

Below 50-60Hz it's very difficult to treat any room, but most of the music is above that anyway so it can only improve one's situation. You can build better bass traps for absorption in the 60Hz and 120Hz range by placing 1/4in and 1/8in plywood panels, respectively, behind the fiberglass panels, but I think it's over kill, unless you know for sure that there is a peak in the room mode for that frequency range. Before treatment in my room, I was getting a nasty peak @ 1.9kHz (very high B-flat and B-natural), loss of bass definition, and lack of clarity in the midrange. After treating with several bass traps, I get more bass definition, better clarity in the midrange, and don't hear that nasty peak @1.9kHz anymore. The sound going into the mics is more damped, tighter, and controlled across the range. Any loss in room ambiance, I can add reverb more predictably, without amplifying the nasty anomalies.

However, the best way to objectively judge is to use a simple room analysis software that's capable of generating a "waterfall" plot of frequency/time/decibels. Or, You can also use your Avensons as a measurement mic, and plot the frequency response from 100-15000Hz using a $30 SPL meter on your DAW software. That way you can see which frequencies are being affected and by how much for your room.

The next 3 weeks are very busy for me, so I unfortunately won't be practicing, playing, or recording much at all. I'll try to make some comparative recordings under controlled conditions, with and without traps soon after that.

If you want I can post pictures of the bass traps in the meantime?...

Let me know if you decide to make your own, I can give more details?...


George

Thank you George for your information. I was considering foam bass traps to put in the corners of my room. I am now envisaging fiberglass panels.

Currently I use the Mic Thing, a foam panel to be mounted on a mic stand, which I put behind the microphone and a cushion above the mics, put at its both ends on the the piano lid edge and on the head of the stand that bears the Mic Thing. The mics are on another mic stand very close to the piano rim, about 20 cm. The preamp gain setting is the same for both clips and there is no audio editing except for compression to mp3.
I get significant results with this setting, which you can judge yourself by listening to the two clips here included, recorded with and without Mic Thing + cushion.

But I have not yet found the clarity that I am looking for.

Hi Didier, thanks for posting the audio clips. Here are some of my observations based just on the 2 clips:

With MicThing+Cushion
Clarity/Definition:--- More Detail
Focus:---------------- Characteristic of Cardiod
Soundstage:--------- Narrower, Boxy, Closed
Tonality:-------------- Nasal, Muffled
Attack/Decay:------- More Damped

Open Mic
Clarity/Definition:--- Smeared Detail in Midrange
Focus:---------------- Characteristic of Omnidirectional
Soundstage:-------- Wider, Open
Tonality:-------------- More Natural
Attack/Decay:------- Lingering Early Reflections


The differences are slight with the Mic Thing and cushion. With the MicThing+Cushion, you're gaining more detail and clarity, but at the expense of producing a narrow and closed soundstage, and with a nasal and less natural tone. The muffled tone could also result from having the cushion too close to the mics, where it becomes to restrictive for the sound. The MicThing and cushion is just a mask, no short cuts here, you really need to treat the room to minimize the undesirable effects.

What everyone should aspire toward is arriving at a "compromised balance." In other words, treat the room to gain just enough clarity, definition, and focus, WITHOUT sacrificing tonality, soundstage, and damping. It will take considerable experimentation to get right. More or less, you have what we all have - Small Room Sound! None of our rooms will ever have a natural lush, open, 3-D, spacious, or deep soundstage. From a practical standpoint, focus on improving clarity and detail by limiting the early type reflections. Once you have achieved a "compromised balance," you can add some reverb to regain additional ambiance. Most software based reverbs are not that great, including mine, because they don't sound natural and emphasize the early reflections, which makes the highs even more shrill and harsh. Convolution Reverbs are better, but still no match for the high end external units like the Bricasti M7... So, if you don't get rid of the early type reflections in your room, I find that the mids and highs become smeared and lose clarity; If you add reverb to this type of sound, it will result in a sound that is unnaturally harsh and edgy - very annoying to listen to after 30seconds!

In addition to the aforementioned sonic improvements I have mentioned before, adding Bass Traps in the corners will also minimize that "one-note" bass room response, which should add individual clarity in the lower bass. You may find that you won't need the MicThing and cushion, especially when you add the bass traps at the sound reflection points on the walls and ceiling. The only benefit of foam panels are that they are lighter. However, my recommendation is to NOT use foam traps, as they are more costly, less predictable, and less effective than fiberglass panels which you can make or buy.