Lol. But then if you don't do it and the 741 sounds really bad in your test, it will be attributed to "a difference in drive capability" and the test dismissed as irrelevant and inconcludent. We know how it works around here. 🙄
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I finally realize an issue around "credibility" of listening experiences. I'm not about to compare op-amps, for instance, via anything other than my Scarlet 2i2, laptop using Foobar or CoolEdit, and my Sennheiser HD650's. If that obviates the exercise to you, well whatever.
BTW earplugs were recommended in the past for some of Mr. Burwen's demos especially his home made recording of an F15 taking off from Hanscom Field.
Then you would also agree that there is some ground to the reluctance of people to being dragged into "audio tests" with setups they have no prior experience with?
I could even build a Diamond buffer for it so it could work well.
Iv'e seen VW bugs with the back seat replaced with a Chevy big block at the drags. Very cool but.....
I have a company to run.😀
Oh and I've actually been getting stellar results by helping out my trusty LT1358/64 with a tube doing the voltage gain. That is a composite that is worth looking into. Next I will try a low noise Jfet. I wondered why it works so good and all you motly crew of T&M EE caged monkeys actually pointed me toward why it works so well.
So for THAT I thank you
An externally hosted image should be here but it was not working when we last tested it.
Would prefer human female voice as an audio playback reference, rather than a jet engine. Not that Dick Burwen is not an excellent designer in his own right, but he switched to IC's in the early 70's, and designed them into Mark Levinson's original studio equipment that he produced before I came on board, in 1973. Later, Mark replaced the IC's with my discrete designs in all his equipment. Even then Dick Burwen could could not hear the difference, so I was told. He brought Mark a working model of the SAME sort of test as is being discussed, e.g. something like 10 quality IC op amps in series, but Mark stayed with discrete for as long as he ran the company.
Yes, I use some Behringer boxes. It questions beliefs about "All Behringer gear is a crap". Some of them are really superb, if you prefer to HEAR the sound, not what PEOPLE SAY. 😀
Does it sound not good, despite of Behringer EQ and reverb? ;-)
How can it be jaw dropping, when recorded on a cellphone? 😀
Edit: and you are right, she is not a professional singer...
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Just two points
1. The internet never forgets
2. Your potential customers do go on the internet.
Worth considering before you broadcast the fact that you don't consider yourself to be an EE. People do get the wrong end of the stick quite easily after all.
Well, it depends... About 10 years ago some High-End store owner spit on me when he heard that I have a MS degree in EE 😀
Some people believe that High End needs Magic, while Science kills it!
Now that Mr Burwen has been mentioned it is interesting to note that his initial design for the Cello Palette used buckets of 5532s.
I didn't start out as a EE. Never got a bachelor's degree. I did go to ITT Tech though and finished the 2 year tech program. The rest was learned on the job and DIY at home. I was an engineering tech when I got laid off at Harman. I don't hide that from anyone.
I have been around music and recording gear all my life. Google "Bob Morin Drums" and you will see my dad's credits.
There ya' go etched forever in the www AGAIN!
Low register close mic'ed sax can cut through grunge easily because the breathyness cuts through and is even embellished by the grunge and compression. The voice gets mangled though by the same.
I've consulted all the sages,
I could find in the yellow pages,
But there aren't many of them...
And the mayan panoramas
On my pyramid pajamas
Haven't helped my little problem ...
😀
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I haven't seen it yet, I am told I got credits on this album for use of my filters.
Vdelli - Out Of The Sun
Dan.
I have two problems here. One is the lack of acknowledgement that simple measurements such as THD do not tell the entire story so it is not unreasonable for some folks to have preferences for sound quality that do not track such measurements.
The second is actually on topic. In a stadium sound system when the announcer is not excited by the action and doing normal stuff like reading statistics the output from a typical dynamic microphone runs around 100 micro volts RMS. As this is a 100 ohmish source and the acoustic noise floor is around 50 dBa, that would require a sound system noise floor about 30 dB below that. As the reinforced sound level for this input level would be mid 70 dBa this only requires about a -55 dB noise floor or roughly 200 nano volts. Quite doable for the typical 8,000 hertz bandwidth of interest with many decent monolithic opamps.
Now when the action gets going and the announcer screams into the microphone the output can actually reach 250 milli volts. This is about 110 dB above the lower level! To get this range the announcer goes from a 1 meter output level of around 60 dBa at a real distance of .5M and then hits 100 dBa at a distance of 1cm!
As a microphone preamplifier normally provides gain of at least 40 dB or AV of 100 with the peak signal of .25 volts RMS this requires an output voltage of 70 volts peak to peak.
Of course the next audio stage cannot handle this so compression is required. Common sense would indicate to limit the gain to 20 dB before the compression. The lower gain requires both the compressor stage and the following gain stage to basically not contribute noise of their own to meet the noise floor. The compressor may actually have to run at a negative gain under some conditions! The gain after the compressor needs to run as much as 40 dB to get the signal level to drive the next stage. All of which is just about doable with the current generation of opamps.
The killer is that folks listen to the noise floor when the venue is empty! That drops the noise floor by 20 to 30 dB. To make things worse folks may actually stick their ears next to the loudspeakers adding another 30 dB to that. Of course if they had their ears at that location during use blood and hearing loss would probably result!
The final insult is of course when they change from a dynamic microphone to a condenser one with 20 dB more output!
The second is actually on topic. In a stadium sound system when the announcer is not excited by the action and doing normal stuff like reading statistics the output from a typical dynamic microphone runs around 100 micro volts RMS. As this is a 100 ohmish source and the acoustic noise floor is around 50 dBa, that would require a sound system noise floor about 30 dB below that. As the reinforced sound level for this input level would be mid 70 dBa this only requires about a -55 dB noise floor or roughly 200 nano volts. Quite doable for the typical 8,000 hertz bandwidth of interest with many decent monolithic opamps.
Now when the action gets going and the announcer screams into the microphone the output can actually reach 250 milli volts. This is about 110 dB above the lower level! To get this range the announcer goes from a 1 meter output level of around 60 dBa at a real distance of .5M and then hits 100 dBa at a distance of 1cm!
As a microphone preamplifier normally provides gain of at least 40 dB or AV of 100 with the peak signal of .25 volts RMS this requires an output voltage of 70 volts peak to peak.
Of course the next audio stage cannot handle this so compression is required. Common sense would indicate to limit the gain to 20 dB before the compression. The lower gain requires both the compressor stage and the following gain stage to basically not contribute noise of their own to meet the noise floor. The compressor may actually have to run at a negative gain under some conditions! The gain after the compressor needs to run as much as 40 dB to get the signal level to drive the next stage. All of which is just about doable with the current generation of opamps.
The killer is that folks listen to the noise floor when the venue is empty! That drops the noise floor by 20 to 30 dB. To make things worse folks may actually stick their ears next to the loudspeakers adding another 30 dB to that. Of course if they had their ears at that location during use blood and hearing loss would probably result!
The final insult is of course when they change from a dynamic microphone to a condenser one with 20 dB more output!
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