You mean like this?
https://londonjazzcollector.files.wordpress.com/2012/08/vonylgrooveelctronmicro.jpg
How do they represent stereo?
Wikipedia is a wonderful "thing"! https://en.wikipedia.org/wiki/Gramophone_record
It is amazing that this method from the stone-age works so well (with noise, wow, futter, clics, pops etc.)
It is amazing that this method from the stone-age works so well (with noise, wow, futter, clics, pops etc.)
So the cantilever amplifies the movement ? or is it 1:1 ?
And...Uhm...thinking about the difference between MM and MC, the latter being superior though difficult to make
And...Uhm...thinking about the difference between MM and MC, the latter being superior though difficult to make
So it resembles a canyon? Just guessing dont know Spanish.
I do not like the look of that debris.
If you look at micro-macrophotographs of the smoothest surfaces ( well, maybe diamonds not !) every detail would show you the truth ...Quartz for example.
Testing Speakers with real music
Back to how speakers work and are tested in simple terms
I want to focus on testing. Usually testing will consist of audio test equipment such as microphones, and at least analysis software, sometimes with testing hardware such as oscilloscopes and sound pressure level metres.
An almost unimaginable display of hardware testing equipment is listed here:
How we test
Testing with instruments is usually supplanted by testing with actual audio tracks. The final product is music, so it only makes sense to test the equipment with music.
As the earlier post said this does it sound like a piano?
Taking this approach, I decided to test my car stereo using music. I initially was going to use a musical instrument sample, however searching for classical guitar music listed the track listed above. No doubt I want to expand my test sample to other instruments and music genres for full testing.
Connecting my smartphone via an internet connection to the aforementioend you tube video, I played the selection.
Initial impressions were somewhat disappointing. Does it sound like a guitar? Well it sounded like a guitar, but not like a real one. There were two failings I detected. One is what I describe as lack of 'attack' which may or may not be the actual term used, but it had simply do do with the sharpness of the notes, how sudenly they appear on the audio stage. The sharpness was not there, the notes seemed to fuzzily creep into existence. The other issue was that the bass simply was not what it should be, the deep notes vibrating through the box section of the guitar on hears when standing really close to the guitar. The sound was not full.
This was all solved by pressing a few buttons on the unit, running throught he equalizer settings, changing them from 'flat' to the pre-programmed 'dynamic' or 'powerful' settings. The bass was now audible and could be really heard, and the power of the strings being plucked resembled that of a real guitar.
Questions remain: did the equalization affect other frequencies? Will the same eq setting introduce distortion or color the sound of other instruments.
My impression is that an equalizer is essential for obtaining the correct frequency balance on speakers that cannot do this on their own. Deficiencies int the speaker can be and msut be corrected by eq but is this Hi-Fi. There is another thread that explores this and must be read before I proceed.
Back to how speakers work and are tested in simple terms
I want to focus on testing. Usually testing will consist of audio test equipment such as microphones, and at least analysis software, sometimes with testing hardware such as oscilloscopes and sound pressure level metres.
An almost unimaginable display of hardware testing equipment is listed here:
How we test
Testing with instruments is usually supplanted by testing with actual audio tracks. The final product is music, so it only makes sense to test the equipment with music.
As the earlier post said this does it sound like a piano?
Taking this approach, I decided to test my car stereo using music. I initially was going to use a musical instrument sample, however searching for classical guitar music listed the track listed above. No doubt I want to expand my test sample to other instruments and music genres for full testing.
Connecting my smartphone via an internet connection to the aforementioend you tube video, I played the selection.
Initial impressions were somewhat disappointing. Does it sound like a guitar? Well it sounded like a guitar, but not like a real one. There were two failings I detected. One is what I describe as lack of 'attack' which may or may not be the actual term used, but it had simply do do with the sharpness of the notes, how sudenly they appear on the audio stage. The sharpness was not there, the notes seemed to fuzzily creep into existence. The other issue was that the bass simply was not what it should be, the deep notes vibrating through the box section of the guitar on hears when standing really close to the guitar. The sound was not full.
This was all solved by pressing a few buttons on the unit, running throught he equalizer settings, changing them from 'flat' to the pre-programmed 'dynamic' or 'powerful' settings. The bass was now audible and could be really heard, and the power of the strings being plucked resembled that of a real guitar.
Questions remain: did the equalization affect other frequencies? Will the same eq setting introduce distortion or color the sound of other instruments.
My impression is that an equalizer is essential for obtaining the correct frequency balance on speakers that cannot do this on their own. Deficiencies int the speaker can be and msut be corrected by eq but is this Hi-Fi. There is another thread that explores this and must be read before I proceed.
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Definitively a no-good approach. You should pursue for the best, anytime.
Example: three way speakers mounted in front of you in a ( acoustically good ) room; good electronics ( just an integrated 20-30 W amplifier and a TT or Cdp; I'm not sure about the quality of FM transmission so Tuners for now stay aside) and excellent software, preferably classic music, from 1600 to 1900
like saying from Scarlatti to Tchaikovsky.
Only then you can start with your "appreciance test"
Not pursuing for the optimum, you are under the influence of so many factors ( errors, mainly )
So if you want to focus on speakers only ( which, together with the room, make the sound ) you have to discard all the errors that may happen before.
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I was outlining a testing method, not the best testing environment, but I get your point.
Subjective Loudness and Frequency
Continuing in the line of the title, I decided to test my speakers using the most rudimentary of all tests, the frequency response test.
After some searching I found this excellent software one that has a sliding scale for changing the frequency. Hooking up my PC speaker hacked amplifier to my now open baffle single range Radio Shack 40-1011 6 inch woofer drivers, I ran the tests.
Frequency response fell into two categories. A range of frequencies would play loudly more or less at the same volume over the frequency range After a certain point both the the higher end and the lower end of the scale, the loudness of the tone as I heard it would drop off markedly. This as I understand is called the roll off.
I was not testing the frequency response using a microphone or analyzer. I use my hearing to detect levels of loudness which is subject of course to the Fletcher-Munson curves. Still, nothing like real life testing.
The lack of bass was not too surprising considering the lack of any sort of baffle, however what was surprising was that the speaker was responding to bass as low as 50Hz which I could detect from a low vibration and hum from the speakers. This is encouraging for the future boxing day plans to place an enclosure around the speakers.
200 Hz to 12000 hz audible standard volume
Absolute limit of audibility 91 Hz to 14k
Online Tone Generator - generate pure tones of any frequency
Drawing tool
Continuing in the line of the title, I decided to test my speakers using the most rudimentary of all tests, the frequency response test.
After some searching I found this excellent software one that has a sliding scale for changing the frequency. Hooking up my PC speaker hacked amplifier to my now open baffle single range Radio Shack 40-1011 6 inch woofer drivers, I ran the tests.
Frequency response fell into two categories. A range of frequencies would play loudly more or less at the same volume over the frequency range After a certain point both the the higher end and the lower end of the scale, the loudness of the tone as I heard it would drop off markedly. This as I understand is called the roll off.
I was not testing the frequency response using a microphone or analyzer. I use my hearing to detect levels of loudness which is subject of course to the Fletcher-Munson curves. Still, nothing like real life testing.
The lack of bass was not too surprising considering the lack of any sort of baffle, however what was surprising was that the speaker was responding to bass as low as 50Hz which I could detect from a low vibration and hum from the speakers. This is encouraging for the future boxing day plans to place an enclosure around the speakers.
200 Hz to 12000 hz audible standard volume
Absolute limit of audibility 91 Hz to 14k
Online Tone Generator - generate pure tones of any frequency
Drawing tool
Attachments
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In the way this interesting discussion has taken on, I think the following lecture will be interesting to watch. The physics of musical instruments:
https://www.youtube.com/watch?v=GFR8UJK3Mzc
https://www.youtube.com/watch?v=GFR8UJK3Mzc
Haven't seen anyone take a crack at this, so I will.
1. You essentially have to decide how loud you'd like your system to be capable of playing without significant distortion. You can try to inform this decision by looking at how loud the sounds you'd like to reproduce are. For example, how loud is a piano, an orchestra, a gunshot (movies), etc. But at some point you have to draw the line - it's impractical, although possible, to make a system that will reproduce the sound of rocket launches at full volume. Such a system would also make you go deaf rather quickly and probably dissolve any house it was used inside. My rough guidelines would be to shoot for max output of 110dB SPL at 1m in 4pi anechoic conditions for a single speaker for a pretty impressive system. This will typically be louder in a room depending on the size and furnishings. You could easily go up or down from here and have something very satisfying. So if you have your maximum output target, then you can look at drivers' sensitivity and see how much power they would take to reach your target. You can model their response in a box and see how much excursion they would need. See if these numbers are within the capabilities of the drivers by looking at the manufacturer's specifications. Then choose an amplifier that will deliver the power you have calculated is needed with the drivers you choose to hit your output target.
2. Try reading Floyd Toole's book - I believe he discusses this a bit. Link: http://www.amazon.com/Sound-Reprodu...F8&qid=1455589659&sr=8-1&keywords=floyd+toole
But directivity is what you should be interested in for changing the imaging of speakers. Low directivity (omni-directional) will be more spacious and distant sounding, higher directivity will be more focussed and forward sounding).
3. Using test tones by themselves is typically not too helpful. Using a measurement program that creates test signals is more useful. Typical signals are swept sine waves or broadband noise. For example, you can test with noise using Speaker Workshop or swept sines using Holm Impulse (both free). There are many Journal of the Audio Engineering Society papers on the merits of using different test signals.
4. This is highly debatable, but I would suggest that whatever type of amp and speaker you use, you measure the response of the drivers during the design process using the amplifiers you plan to use if they are anything odd (tube amps, etc.), and that you ensure both speakers and amplifiers have enough headroom to produce the levels you desire without significant distortion. There are many threads here at DIYaudio that go into much greater detail on this subject.
5. This is the same as building any other type of speaker. You're just putting the subwoofer in its own box. Make sure the satellite and subwoofer have frequency responses and levels that allow them to blend together smoothly to produce the response you want in your room.
Update: Just purchased and am reading this one:
Designing, Building, and Testing Your Own Speaker System with Projects Kindle Edition
by David Weems
Fascinating stuff, clearly explained. The first few pages have more useful info than I have come across in many other sources.
Will reply other posts, thanks.
Designing, Building, and Testing Your Own Speaker System with Projects Kindle Edition
by David Weems
Fascinating stuff, clearly explained. The first few pages have more useful info than I have come across in many other sources.
Will reply other posts, thanks.
John, thank you:
Thanks for the advice. My question was actually if a book would adress the loudness factor specifically, so far I have not seen much although I am reading Tool's book online - at least the review part.
Loudness levels are a critical part of the Hi-Fi experience - from a health and safety issue (even orchestra musicians are exposed to dangerous levels of sound) to civic issues such as playing music too loud for the neighbours. I have been guilty of this in my younger days, in order to 'hear all the sounds' But a proper system would have me hear all the sounds at lower levels.
I am reading a part of the book from the review. It is a very comprehensive text with much in depth detail.
Basically I want to walk around in my room and experience stereo. Speaker placement, toe-toe in and raking the speakers (upward pointing slightly) should help. Interestingly the latter is mentioned in David B Weem's book : Designing, Building ..."
3. Yes will try test sine wave sweeps. I can then record the levels at different frequencies
I am more concerned with damaging the speakers. According to an article I read, distortion is not really detectable unless levels get over 5%. It is good advice to test the speakers with the ampifier and the room it is inteded for.
5.Maybe, but I think there are some issues specific to satellite subwoofer systems that I would like to see adressed. There are lots of design choices.
Thanks for the advice. My question was actually if a book would adress the loudness factor specifically, so far I have not seen much although I am reading Tool's book online - at least the review part.
Loudness levels are a critical part of the Hi-Fi experience - from a health and safety issue (even orchestra musicians are exposed to dangerous levels of sound) to civic issues such as playing music too loud for the neighbours. I have been guilty of this in my younger days, in order to 'hear all the sounds' But a proper system would have me hear all the sounds at lower levels.
I am reading a part of the book from the review. It is a very comprehensive text with much in depth detail.
Basically I want to walk around in my room and experience stereo. Speaker placement, toe-toe in and raking the speakers (upward pointing slightly) should help. Interestingly the latter is mentioned in David B Weem's book : Designing, Building ..."
3. Yes will try test sine wave sweeps. I can then record the levels at different frequencies
I am more concerned with damaging the speakers. According to an article I read, distortion is not really detectable unless levels get over 5%. It is good advice to test the speakers with the ampifier and the room it is inteded for.
5.Maybe, but I think there are some issues specific to satellite subwoofer systems that I would like to see adressed. There are lots of design choices.
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Halfway through this video. He does a very good job of explaining how instruments work.
The explanation of pipes is particularly relevant to understanding ported speakers and speaker boxes in general. The part on box resonance shows what a speaker should not do - at least at high frequencies.
Completed the full video, very useful stuff.
Here is another one: https://www.youtube.com/watch?v=NLGQnxIP2gE
RAF 10. Paul Barton, PSB speakers. He has been building speakes for 40 years.
Notable quotes "The difference between live music and reproduced music is dynamics"
He says the most difficult part is producing the same speaker in production as in the prototype.
Here is another one: https://www.youtube.com/watch?v=NLGQnxIP2gE
RAF 10. Paul Barton, PSB speakers. He has been building speakes for 40 years.
Notable quotes "The difference between live music and reproduced music is dynamics"
He says the most difficult part is producing the same speaker in production as in the prototype.
Suggested music for testing speakers
Testing speakers - sample reference material.
It has often been recommended to test speakers using music you listen to. My initial listening tests have shown that whereas popular music is quite listenable on a the smallest of speaker systems for example, classical orchestra music requires a speaker/amplfier combination with a good dynamic range (and power handling) to play the quiet passages as well as the very loud ones.
The following material has been suggetested for testing speakers:
https://list.ly/list/HQe-7-best-songs-for-testing-speakers-or-headphones
Best Songs to Test Speakers | What Hi-Fi?
Music to test speakers with | BUILD
I don't see any classical music on the list:
May I add the following : any suggestions?
Beethoven's 5th Symphony - YouTube
https://www.youtube.com/watch?v=_4IRMYuE1hI
Stravinsky: The Firebird / Gergiev · Vienna ...
https://www.youtube.com/watch?v=RZkIAVGlfWk
Testing speakers - sample reference material.
It has often been recommended to test speakers using music you listen to. My initial listening tests have shown that whereas popular music is quite listenable on a the smallest of speaker systems for example, classical orchestra music requires a speaker/amplfier combination with a good dynamic range (and power handling) to play the quiet passages as well as the very loud ones.
The following material has been suggetested for testing speakers:
https://list.ly/list/HQe-7-best-songs-for-testing-speakers-or-headphones
Best Songs to Test Speakers | What Hi-Fi?
Music to test speakers with | BUILD
I don't see any classical music on the list:
May I add the following : any suggestions?
Beethoven's 5th Symphony - YouTube
https://www.youtube.com/watch?v=_4IRMYuE1hI
Stravinsky: The Firebird / Gergiev · Vienna ...
https://www.youtube.com/watch?v=RZkIAVGlfWk
Procedure for Testing Speakers - First Attempt
Using one of the above lists, and using the YouTube video for the above tracks, I proceeded to test my car audio system using music.
Testing in the car: Result: OK (due to less than CD quality of tracks?)
On the plus side, the quality if good recording of vocals was evident, and the system could produce the vocals in good detail.
Steely Dan - Jack of Speed
Steely Dan is one of my favourite artists. I had not heard the track before, however I was selecting the preset equalizer settings to obtain the best sound from car audio system. The quality of the You Tube tracks (or lack of it) could be the reason for the lack of quality and need for adjustment.
Daft Punk- Get Lucky
A more recent song, and one of my favourite, with the guitar accompaniment throughout the song. The recording features the vocalist very prominently, the other instruments seem to be somewhat faded in the background. I could almost hear the vocalist breathe.
Crooked Still - Little Sady
A vocal - intensive track.
Stevie Ray Vaughn - Tin Pan Alley
A highly engaging song, once again vocals are recorded in fulness of detail. Sparse instrumentation seems to help.
Moloko - I want you
The track contains some unusual sounds that did not sound good at all on my system. Maybe that's the point of the test?
Testing my single PC speaker system produced a sound that was pleasant, but simply not enough detail in the mid range and almost no bass. Once the cabinet is completed, this should improve.
The softer passages in classical music simply cannot be heard in any sort of detail at low volumes, but popular music seems to be produced to stay within the dynamic range of the common music box and sound good at the same time. In fact, I remember a particular video of Hall and Oates in which they played the track through small speakers to adjust the final sound of the track in question.
Using one of the above lists, and using the YouTube video for the above tracks, I proceeded to test my car audio system using music.
Testing in the car: Result: OK (due to less than CD quality of tracks?)
On the plus side, the quality if good recording of vocals was evident, and the system could produce the vocals in good detail.
Steely Dan - Jack of Speed
Steely Dan is one of my favourite artists. I had not heard the track before, however I was selecting the preset equalizer settings to obtain the best sound from car audio system. The quality of the You Tube tracks (or lack of it) could be the reason for the lack of quality and need for adjustment.
Daft Punk- Get Lucky
A more recent song, and one of my favourite, with the guitar accompaniment throughout the song. The recording features the vocalist very prominently, the other instruments seem to be somewhat faded in the background. I could almost hear the vocalist breathe.
Crooked Still - Little Sady
A vocal - intensive track.
Stevie Ray Vaughn - Tin Pan Alley
A highly engaging song, once again vocals are recorded in fulness of detail. Sparse instrumentation seems to help.
Moloko - I want you
The track contains some unusual sounds that did not sound good at all on my system. Maybe that's the point of the test?
Testing my single PC speaker system produced a sound that was pleasant, but simply not enough detail in the mid range and almost no bass. Once the cabinet is completed, this should improve.
The softer passages in classical music simply cannot be heard in any sort of detail at low volumes, but popular music seems to be produced to stay within the dynamic range of the common music box and sound good at the same time. In fact, I remember a particular video of Hall and Oates in which they played the track through small speakers to adjust the final sound of the track in question.