Hello,
I'm interested in building a pair of binaural microphones, and use a dummy head.
First, I don't know much about electricity, I just do possible simple stuff from time to time, so talk simple to me, guys.
I assume that the weakest part of cheap recorders (MD's or HD recorders) are the preamps. So, it's logical to push the mics to line level, and adjust the proper output impedance. Many recorders have line input but not all of them got line input.
Looking at Linkwitz's design (is this guy thrustworthy or what?) :
http://www.linkwitzlab.com/sys_test.htm#Mic
Do you guys think that it's a good base for a stereo schematic?
How should this simple preamp compare to the ones found in sub $400 recorders? (and even the new Sony Hi-MD's?)
If so, what will happen if I share these batteries with the second mic? What should I change in this schematic if I want to add the second mic?
There's also Rod Elliot's version (look at the one with the preamp):
http://sound.westhost.com/project112.htm
I don't have the slightest idea what would be better (-:
By the way, where's a good place to buy these Panasonics that also has a large selection of electronic parts? (Like Mouser, bt they don't have them)
Thanks
Adam
I'm interested in building a pair of binaural microphones, and use a dummy head.
First, I don't know much about electricity, I just do possible simple stuff from time to time, so talk simple to me, guys.
I assume that the weakest part of cheap recorders (MD's or HD recorders) are the preamps. So, it's logical to push the mics to line level, and adjust the proper output impedance. Many recorders have line input but not all of them got line input.
Looking at Linkwitz's design (is this guy thrustworthy or what?) :
http://www.linkwitzlab.com/sys_test.htm#Mic
Do you guys think that it's a good base for a stereo schematic?
How should this simple preamp compare to the ones found in sub $400 recorders? (and even the new Sony Hi-MD's?)
If so, what will happen if I share these batteries with the second mic? What should I change in this schematic if I want to add the second mic?
There's also Rod Elliot's version (look at the one with the preamp):
http://sound.westhost.com/project112.htm
I don't have the slightest idea what would be better (-:
By the way, where's a good place to buy these Panasonics that also has a large selection of electronic parts? (Like Mouser, bt they don't have them)
Thanks
Adam
hi
I have a couple of National Panasonic WM-034 at home.
Very good electret microphones in relation to low price!
WM-61A is even better, and to prefer, what they say.
But I took what could find.
At this panasonic page you can download PDF Datasheets for your microphone WM-61
http://www.panasonic.com/industrial/components/audio/aud_mic.htm
Yours:
http://www.panasonic.com/industrial/components/pdf/em06_wm61_a_b_dne.pdf
Here is mine, WM-034:
http://www.panasonic.com/industrial/components/pdf/em14_wm034_b__db_c_d_dne.pdf
WM-61
WM-034
lineup 😎 the microphone amplifier builder
I have a couple of National Panasonic WM-034 at home.
Very good electret microphones in relation to low price!
WM-61A is even better, and to prefer, what they say.
But I took what could find.
At this panasonic page you can download PDF Datasheets for your microphone WM-61
http://www.panasonic.com/industrial/components/audio/aud_mic.htm
Yours:
http://www.panasonic.com/industrial/components/pdf/em06_wm61_a_b_dne.pdf
Here is mine, WM-034:
http://www.panasonic.com/industrial/components/pdf/em14_wm034_b__db_c_d_dne.pdf
WM-61
An externally hosted image should be here but it was not working when we last tested it.
WM-034
An externally hosted image should be here but it was not working when we last tested it.
lineup 😎 the microphone amplifier builder
Linkwitz and Elliot are extremely respectable and anything on their sites is well thought out.
The mod on the pana mic is necessary but may be a little bit tricky if you have no soldering experience.They mikes are very cheap and you can buy a dozen if you can find some in small quantities to experiment.A preamp may not be necessary depending on recording levels and gain of MD.Otherwise quality can be very very good although personally I found that playing thru speakers needs some bass eq cut.
Ideally you should try and match the two stereo mikes for close output levels so getting some extra mikes is always a good idea.
The mod on the pana mic is necessary but may be a little bit tricky if you have no soldering experience.They mikes are very cheap and you can buy a dozen if you can find some in small quantities to experiment.A preamp may not be necessary depending on recording levels and gain of MD.Otherwise quality can be very very good although personally I found that playing thru speakers needs some bass eq cut.
Ideally you should try and match the two stereo mikes for close output levels so getting some extra mikes is always a good idea.
protos said:
So, looking at Linkwitz's stereo schematic, what will be the output impedance?
IIRC, the optimal ratio between output and input impedance is about 1/10. Is that correct?
Thanks!
I used an INA217 with the WM-61. It's just based on the datasheet at www.ti.com. Simplest solution for best performance. I can change the gain by plugging in different resistors into a DIP socket.
paulb said:
Thanks for the Burr-Brown / Texas INA217 info, paulb
( This is a replacement of much used and good SM2017 mic amp IC )
Here a very nice project using this INA217 ( SM2017 )
with 2 High quality LM833 OP-amps for the output.
Included many schematics and pictures!
KDMP - Kev's Dual Mic Pre in a rack box
http://www.celestial.com.au/~rosswood/diy/KDMP/kdmp.htm
lineup 😎 microphone web search service
Well, I've decided that my player with be the Sony MZ-NH600.
It's a HI-MD player that works on AA. Only line ins. However, I don't know if it's possible (or easy) to change recording levels from it on the fly.
I want the rig to be very portable, So it's either Elliot or Linkwitz's design.
As the discussed circuits are all quite small, quality is the first thing to consider. OTOH, I hope I won't have to carry more then 2 9V batteries in this pack (and get reasonable battery life).
But I still didn't get a straight answer from anyone about what input level and impedance should the line in section in the MD player "see" , considering that it's the modded capsule used.
Linkwitz staits the specs of the WM-61A's capsule and his circuit but honestly I don't really understand it, translate it to my needs, and choose one of his circuits, or maybe Rod's.
Let's reorder things:
Linkwitz's single channel 10dB preamp version (/w WM-60AY)
Linkwitz's dual channel (no preamp)
Elliot's P112, with the electret capsule mod preceding it
It's a HI-MD player that works on AA. Only line ins. However, I don't know if it's possible (or easy) to change recording levels from it on the fly.
I want the rig to be very portable, So it's either Elliot or Linkwitz's design.
As the discussed circuits are all quite small, quality is the first thing to consider. OTOH, I hope I won't have to carry more then 2 9V batteries in this pack (and get reasonable battery life).
But I still didn't get a straight answer from anyone about what input level and impedance should the line in section in the MD player "see" , considering that it's the modded capsule used.
Linkwitz staits the specs of the WM-61A's capsule and his circuit but honestly I don't really understand it, translate it to my needs, and choose one of his circuits, or maybe Rod's.
Let's reorder things:
Linkwitz's single channel 10dB preamp version (/w WM-60AY)
Linkwitz's dual channel (no preamp)
Elliot's P112, with the electret capsule mod preceding it
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
One Sony MD that I have used before, I did not even need a preamp or battery. It supplied aournd 2.5V phanton power. All I had to do was hook the panasonic capsules into the MD using a 3.5mm earphone plug. I actually moded a set of earphones and used that. The MD I used allow changing volume level on the fly. One thing though is that the recording was polarity inverted. For best results, it needs to be inverted back during playback.
AdamZuf said:Well, I've decided that my player with be the Sony MZ-NH600.
It's a HI-MD player that works on AA. Only line ins. However, I don't know if it's possible (or easy) to change recording levels from it on the fly.
I want the rig to be very portable, So it's either Elliot or Linkwitz's design.
As the discussed circuits are all quite small, quality is the first thing to consider. OTOH, I hope I won't have to carry more then 2 9V batteries in this pack (and get reasonable battery life).
But I still didn't get a straight answer from anyone about what input level and impedance should the line in section in the MD player "see" , considering that it's the modded capsule used.
Linkwitz staits the specs of the WM-61A's capsule and his circuit but honestly I don't really understand it, translate it to my needs, and choose one of his circuits, or maybe Rod's.
Let's reorder things:
Linkwitz's single channel 10dB preamp version (/w WM-60AY)
Linkwitz's dual channel (no preamp)
Elliot's P112, with the electret capsule mod preceding it
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
WM-61A Panasonic elektret microphone capsule Linkwitz
hi
Linkwitz used WM-60A
in his first set up, as seen in his schematics
with modified elektret input-JFET mic transistor circuit.
As told by previous poster here
WM-61A can be used to replace with improved performance.
somewhat higher sound sensitivity and lower noise
-----------------------------------------------------------------------------
For those in northern Europe,
who would want to try the very good (performance/price)
Mic capsule Panasonic WM-61A
.... we have a supplier here
Prices: (I think maybe you can find lower price at some bigger electronics suppliers)
For delivery inside EU
1-4 pcs WM-61A EUR 6.94
5-9 pcs WM-61A EUR 5.76
10+ pcsWM-61A EUR 4.59
StartPage http://www.svalanderaudio.com/
Some good stuff for Vinyl Turntables
.. like extremely good Cartridges Nagaoka ! Ortofon etc. and other fancy Vinyl Accessoires.
VinylPage-Shop: http://www.svalanderaudio.com/vinyl/vinyleng.php
lineup - North Europe
hi
Linkwitz used WM-60A
in his first set up, as seen in his schematics
with modified elektret input-JFET mic transistor circuit.
As told by previous poster here
WM-61A can be used to replace with improved performance.
somewhat higher sound sensitivity and lower noise
-----------------------------------------------------------------------------
For those in northern Europe,
who would want to try the very good (performance/price)
Mic capsule Panasonic WM-61A
.... we have a supplier here
An externally hosted image should be here but it was not working when we last tested it.
http://www.svalanderaudio.com/shoppen/mik.php
Prices: (I think maybe you can find lower price at some bigger electronics suppliers)
For delivery inside EU
1-4 pcs WM-61A EUR 6.94
5-9 pcs WM-61A EUR 5.76
10+ pcsWM-61A EUR 4.59
StartPage http://www.svalanderaudio.com/
Some good stuff for Vinyl Turntables
.. like extremely good Cartridges Nagaoka ! Ortofon etc. and other fancy Vinyl Accessoires.
VinylPage-Shop: http://www.svalanderaudio.com/vinyl/vinyleng.php
lineup - North Europe
Re: WM-61A Panasonic elektret microphone capsule Linkwitz
I vaguely recal they were much less at Digikey.
lineup said:
I vaguely recal they were much less at Digikey.
thanks for info
yes, if I will purchase
I surely will have a look around.
Small private 'audiophile' sellers, can naturally not buy and store
so big quantities as big suppliers/resellers.
( The bigger orders from manufacturers - the lower the price per part. )
So price will often not be the ultimate in small places.
But there are exceptions ...
In many cases the service and personal support
can be a very good factor at small web shops.
As well as good audio support knowledge given personally.
This is a way to get very happy customers - when you can't compete with ultimate prices.
christmas
lineup
yes, if I will purchase
I surely will have a look around.
Small private 'audiophile' sellers, can naturally not buy and store
so big quantities as big suppliers/resellers.
( The bigger orders from manufacturers - the lower the price per part. )
So price will often not be the ultimate in small places.
But there are exceptions ...
In many cases the service and personal support
can be a very good factor at small web shops.
As well as good audio support knowledge given personally.
This is a way to get very happy customers - when you can't compete with ultimate prices.
christmas
lineup
"Plug-in" power is what you are talking about, and it's available only on the mic input of some MD recorders. So of coarse you didn't need a preamp, it was already in the MD unit.
So to remind, mine won't have a mic input.
So many posts after my last one and still no straight answer
Help!
AdamZuf said:
So many posts after my last one and still no straight answer
Quote: many posts ... no straight answer
--------------------------------
think you have got plenty of good hints, mate
But if you want more ....
than what we try to give you spending our time writing replies here
asking for nothing in return - like money for our support ...
... then you may have to wait
Or you ask a better questions
-- what are you really asking for, what you want ????
..................
I, me, lineup,
Has done my best to inform.
Now,
I move on to other topics, than this.
I resign.
Godday 😉
AdamZuf said:
"Plug-in" power is what you are talking about, and it's available only on the mic input of some MD recorders. So of coarse you didn't need a preamp, it was already in the MD unit.
So to remind, mine won't have a mic input.
So many posts after my last one and still no straight answer
Help!
I think you will have to calculate it yourself.
First, determine what the clipping input voltage is. (ask Sony tech support or look in the manual.
Second, decide what maximum sound level you wish to record and and the average noise level of the mic you might use. Determine the dynamic range.
Third, divide the dynamic range by the clipping voltage, and you have the mic+preamp sensitivity you probably want.
Forth, after you have done the above, you will have questions, then ask.😀
Or maybe it would be simpler to just buy an MD recorder/player that has a mic input.
AdamZuf said:
Look up the specs on your Sony line in. It's probably about 10K, maybe higher. If that's the case, no worries, the preamp will be much lower.
Also, as stated above, find out what voltage in gives you 0dB or what is "max" (if you can). That will give you an output level to work toward for your mic preamp. You want plenty of level, because you can always turn down the inputs.
Don't take it so hard, man... and I'm sorry if If I made you guys mad, but I don't understand much about the math of it, and it's not suppose to be that hard for you DIY'ers who do it like everyday...
I just want the mic circuit to match a consumer line level input (it can be generalised, can't it), portable, best quality I can (I don't have experience listening to different opamps, or dealing with impedance mismatch), and battery life as a second priority.
Is it that complicated, guys?🙁
Lots of people ask for help because they are studying and want to understand. To get the best quality YOU can means you have to study too. If you think it's not worth the time, then probably just take whatever schematic that looks okay and just do it, I'm sure people will aswer questions if you run into trouble doing it.AdamZuf said:
Well I searched for comparisons about the NE5532 and the OPA2134, but realised it's just a matter of listening myself to the whole circuit.
I also realized that it's important that the circuit to have a volume pot.
In Linkwitz's 10dB preamp, can I add one in instead of the 10K feedback resistor?
Thanks
Adam
I also realized that it's important that the circuit to have a volume pot.
In Linkwitz's 10dB preamp, can I add one in instead of the 10K feedback resistor?
Thanks
Adam
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