You are the one to say so. Your disparaging comments like "many here do not have a clue ....." are famous.
"Funny" I meant that the clean one was called dirtier. This is very usual that distorted is considered cleaner. I would not expect it on a sine tone. But in this case, I assume no one would tell the difference in ABX.
The problem with audio is that we often make a choice of something that is pleasing our imperfect or flawed hearing, even if it distorts the sound. Of course, impossible to admit
But if you do it right you can make money off it. An interesting piece of studio equipment is called the Aphex Aural Exciter, not the "Aphex Aural Distorter."
I have 40yr. old Primo capsules that are spot on exactly as they were day 1 (except for the one someone gobbed his tobacco on). They invented backgate electret to put the charge on the plate behind the diaphragm. The Primo capsules were the basis of Nakamichi's CM-300 series of mics, still highly sought after by stealth concert tapers. IIRC DPA's top of the line (~$3000) 4006A is electret based. They say pre-polarized condensor.
Did-you tried their sensitivity ?
I ask this question, because I have a couple of very flat little capsules that I used for multiple purposes, and had the feeling they have lost some dBs (more noisy) since the first day.
Feeling, not measured.
I know for the back plate polarisation. But is-it possible to make a symmetric device, as you rightly pointed out ?
I have nothing against electret, on the contrary, I remember one (Shure ?) we had on tes witch sounded, at my surprise, not so far from an average U67 in cardioid.
An other question, I had never seen a large diaphragme Electret. Why, if it does not exist ?
Yes, the Primo's are low 10mV/Pa in their base form but have stayed that. There are 26mm electrets, TSB-2555AXZ3-GP - Transsound
Note - The Transound data sheets are very confused and no one has been able to clear them up. The capsules are all speced as having an internal FET even if they don't.
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You need solder with copper content to reduce dissolving of copper plus minimum soldering temperature possible, standard Pb/Sn is sub optimal.Thanks. Definitely. Seems you are experienced in this domain..
I use Pb/Sn only, and time is the absolute enemy. tenth second, quarter second max, and tip very close to 190C.
jn
Leadfree with copper works for me, ie Tin 99.3%/Cu 0.7%.
Dan.
Pavel, I just had a look in Reaper and it reports levels of -6.8db for A and -6.5db for B.
I assumed that you had level matched the two tracks hence my questioning the reason for the perceived (slight) level difference.
I believe I am owed apology for your remarks.
In future please ensure that your listening tests are technically correct before passing disparaging comment on others.
That you generally find my findings not reflecting reality serves to reveal your dogmatism and in this particular case your incompetence in presenting a technically valid test.
Dan
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I assumed that you had level matched the two tracks hence my questioning the reason for the perceived (slight) level difference.
I believe I am owed apology for your remarks.
In future please ensure that your listening tests are technically correct before passing disparaging comment on others.
That you generally find my findings not reflecting reality serves to reveal your dogmatism and in this particular case your incompetence in presenting a technically valid test.
Dan
Edit:
Your test is flawed, not me in this case, go ahead and admit it and learn by it.The problem with audio is that we often make a choice of something that is pleasing our imperfect or flawed hearing, even if it distorts the sound. Of course, impossible to admit
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JN stated he is using standard solder.
Ime with such very fine wires using standard solder is recipe for problems, ie disappearing wire.
I understand that JN is familiar with large conductors, I am giving friendly heads up for when dealing with the fine stuff.
There are reasons for using silver or gold solder alloys also.
Dan.
Condenser microphones have been around for quite some time. In World War II the Japanese used electret condenser microphones in their field radios. The back electret was made of carnauba wax that was solidified under a high voltage field. As it fed a vacuum tube stage high impedance load the greater voltage compared to a dynamic microphone was an advantage. (Carbon microphones were given heavy use in the prior World War I.)
Western Electric made many of the first external DC polarized condenser microphones. These used a gold diaphragm as gold can be rolled extremely thin. The one I had was a cardioid version that had a rolled surround.
Sennheiser was the first with an RF version where the capsule was the tuning element in an oscillator running at Radio Frequencies. That produced a Frequency Modulation signal that then followed the standard demodulation techniques of the time. That involved a "Discriminator" circuit using a sort of balanced transformer. The reason FM was more popular in Europe after World War II was that with all the close nations there wasn't enough Amplitude Modulated radio station bandwidth available. In addition the Allies pretty much imposed Frequency Modulated radio stations as the only choice for the nations being rebuilt.
Many years ago some idiot wrote an article about how to use a differential stage to feed a balanced line. After that transformers really started disappearing from microphones. The earliest circuits that did not use a transformer were really single ended and just used a resistor to have approximately equal source resistance on the other source terminal. For proprietary reasons the example circuit showed the collectors driving the line, but almost everyone figured out it really should be the emitters.
When David Blackmer (Formerly of dBx) started selling his Earthworks electret condenser microphones he encapsulated the circuit to keep it a secret.
Western Electric made many of the first external DC polarized condenser microphones. These used a gold diaphragm as gold can be rolled extremely thin. The one I had was a cardioid version that had a rolled surround.
Sennheiser was the first with an RF version where the capsule was the tuning element in an oscillator running at Radio Frequencies. That produced a Frequency Modulation signal that then followed the standard demodulation techniques of the time. That involved a "Discriminator" circuit using a sort of balanced transformer. The reason FM was more popular in Europe after World War II was that with all the close nations there wasn't enough Amplitude Modulated radio station bandwidth available. In addition the Allies pretty much imposed Frequency Modulated radio stations as the only choice for the nations being rebuilt.
Many years ago some idiot wrote an article about how to use a differential stage to feed a balanced line. After that transformers really started disappearing from microphones. The earliest circuits that did not use a transformer were really single ended and just used a resistor to have approximately equal source resistance on the other source terminal. For proprietary reasons the example circuit showed the collectors driving the line, but almost everyone figured out it really should be the emitters.
When David Blackmer (Formerly of dBx) started selling his Earthworks electret condenser microphones he encapsulated the circuit to keep it a secret.
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I was on micbuilders years before this and did tear downs on Panasonic capsules. There is not a lot to learn from these but it is fun to measure the diameter and thickness of the spacer and get the right capacitance. Interpreting the cavity dimensions and hole patterns and making thoughtful modifications would require a Phd in acoustics. In the end someone already optimized these little things and no amount of DIY mods are going to improve the SNR, etc. (beyond the Linkwitz mod which is an application issue). The idea of substituting a fancy FET never seems to go away, it almost always makes things worse.
Schoeps had transformerless mics in 1964, are you calling them idiots? I knew Dave, he would probably pot a circuit to hide the fact that he was doing the Linkwitz mod on cheap capsules. Please no fights, just clarify.
EDIT - Just checked the EW data sheets no physics has been violated the specs are typical for small electret capsules so maybe you could enlighten us on what there was to hide.
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Not exactly true for Belgium and France, Simon.
AM long waves stations where the only one in France during a very long time). One owned by the French state (France Inter owned by Radio France)), and two or 3 commercials (Europe1, Radio télé Luxembourg, Radio Monte-Carlo) situated outside, but near the border. One unique Huge emitter covering all ouest Europa for all of them. And some 'medium waves' stations, more confidential or local.
.
To make the story short, FM appeared in 1954, for quality reasons, by Radio France, with the same programs than AM and it took some time to cover all the territory. 3 programs (France Inter, France Culture, France Music) all owned by Radio France.
From the 70, several illegal attempts of private or local FM radios, repressed by the state, phenomena that increased underground till 1977 with the explosions of "Free radios", illegal but tolerated until 1981, when the state regularized the situation by granting frequencies to the largest of them...Who bought the frequencies of the smallest ones or those of Province to extend their network.
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Sorry, my mistake, it was only for the response curve at the end of the page. I had not even read the previous.
As usual...
What he was hidding was not the capsule but the balancing circuit. The older output circuits generally were not balanced or even truly differential. They were avoiding transformers. Today output transformers are quite rare, although some of the cheap electret condenser microphones use rather inexpensive transformers.
Tourney,
Last I knew Belgium and France were not Axis members and not subject to the same restrictions. Germany was pretty much so ignored in the 1948 conference allocating spectrum in Europe. As FM was not included they started using it and I believe it was called UKW.
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The problem with the entire premise of adding copper, is that it raises the melt temp anyway. Adding it to reduce dissolution is just a long standing myth as it requires a higher temp to compensate anyway.. I cringe every time I read some article on process optimization, most have no clue as to the metallurgy and or flux chemistry.
I prefer eutectic for fine wires because it's 183 C and copper dissolving (formation of copper tin inter metallics) is slower and consistent. Using lead free means higher melt temperatures, and a quicker dissolving of copper.
I was on the forefront of using lead free, as that was the only thing we could use back in the day with superconducting joints (the lead is weakly superconducting so messes up the current distribution). I was consuming tons of it (lead free, or tin silver eutectic) before anybody ever heard of it, and had to give advice to the military on it's use decades ago. (apparently they called me for advice because I was the biggest consumer of lead free solder on the planet at the time).
By hand, I always recommend a high mass tip with temp set low, the smaller tips with controlled temp, most people tend to set the tip temp way too high for expediency and end up overheating plastics, epoxies, or dissolving small wires.
While that may be true, it was a sincere comment, he was correct on the difficulty in soldering to wires I can no longer see without magnification.
Actually, the lead really doesn't consume the copper. It is the copper/tin inter-metallic formation that consumes the copper. The real issue is, because the eutectic temp is so low, and most have the tip temp too high, that copper is consumed most rapidly.
I deal with conductors from an inch or two in diameter down to 1.5 mil copper or .7 mil gold so have a wide experience base. However, your words are good. I appreciate the friendly heads up sentiment..thank you.
Jn
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PMA, sorry about not getting to this sooner.
Unfortunately the measurement is not quite what I need. The THD .wav file needs to be calibrated to the speaker current, not voltage.
1: Measure SPL and phase vs frequency vs speaker current (voltage or current drive)
2: Measure THD without moving the microphone. Measure at 201.1Hz so it is an irrational factor of the samplerate.
3: Apply the phase/frequency correction to the whole THD spectrum so that every harmonic phase shift is relative to speaker current. The correction should also be applied to the THD .wav file.
If you cannot do step 3, then post the .wav file and mag/phase .txt file and I will try to get it done. Perhaps someone here smarter than me can perform that step. Then the resulting .wav file can be used to analyze harmonics. At the very least the correction can be applied to the FFT.
Unfortunately the measurement is not quite what I need. The THD .wav file needs to be calibrated to the speaker current, not voltage.
1: Measure SPL and phase vs frequency vs speaker current (voltage or current drive)
2: Measure THD without moving the microphone. Measure at 201.1Hz so it is an irrational factor of the samplerate.
3: Apply the phase/frequency correction to the whole THD spectrum so that every harmonic phase shift is relative to speaker current. The correction should also be applied to the THD .wav file.
If you cannot do step 3, then post the .wav file and mag/phase .txt file and I will try to get it done. Perhaps someone here smarter than me can perform that step. Then the resulting .wav file can be used to analyze harmonics. At the very least the correction can be applied to the FFT.
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