New to Home Recording/mic issues

Thank you Mark for some actual facts! I feel somewhat vindicated about my reservations.

Jacob. did not know you could still return the mic! (ain't it a B*****! How info dribbles out of forums?) Whole new slant on things.SO yes, chop the Nt1a in for a dynamic (shame but hey ho) and get a dynamic. Also get one of these Microphone Matching Transformer: Amazon.co.uk: Musical Instruments

That will sort out the balance problem and give a few dB lift into the kbd pre amp. My son uses one very successfully to get an SM57 into a looper. Now, all the mics , mentioned are fairly expensive so you could try a Behringer XM 8500. They are a bit more sensitive than the 57/58s and sound far better than they should for $20 and if it doesn't suit you are only out 20 bucks and you have a spare mic..OR lob it on the Bay, bet you would get 2/3ds of your money back.

The transformer will be useful for any dynamic mic you get.

Dave.
 
ecc83 said:
Thank you Mark for some actual facts! I feel somewhat vindicated about my reservations.

Jacob. did not know you could still return the mic! (ain't it a B*****! How info dribbles out of forums?) Whole new slant on things.SO yes, chop the Nt1a in for a dynamic (shame but hey ho) and get a dynamic. Also get one of these Microphone Matching Transformer: Amazon.co.uk: Musical Instruments

That will sort out the balance problem and give a few dB lift into the kbd pre amp. My son uses one very successfully to get an SM57 into a looper. Now, all the mics , mentioned are fairly expensive so you could try a Behringer XM 8500. They are a bit more sensitive than the 57/58s and sound far better than they should for $20 and if it doesn't suit you are only out 20 bucks and you have a spare mic..OR lob it on the Bay, bet you would get 2/3ds of your money back.

The transformer will be useful for any dynamic mic you get.

Dave.
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Not sure a matching tranny is necessary. For a looper that may have a Hi-Z input for a guitar probably, but I recall researching this a while back for my own Yammy arranger and while the specs in any normal user docs don't seem to convey a recommended mic impedance, the service manual does show it. I would presume the Yammy DGX660 may be of a similar spec for it's mic input although nowhere to be found. I think I tried a matching tranny with mine years ago and it did something to the mic freq response, but maybe if I find the time I'll give it another go.

A screen shot below of the user manual of an old PSR-740 also suggests a Lo-Z mic. The sidebar on the right side mentions an MZ106s which I found an image of and it does have an XLR connector.

I do have a few of those matching transformers around gathering dust that I used to use on old cassette multitrack machines :)
 

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I don't see an impedance listed for the mic, but on page 69 it does say:

NOTE:
Make sure to use a conventional dynamic microphone.
 
arcaxis said:
Not sure a matching tranny is necessary. For a looper that may have a Hi-Z input for a guitar probably, but I recall researching this a while back for my own Yammy arranger and while the specs in any normal user docs don't seem to convey a recommended mic impedance, the service manual does show it. I would presume the Yammy DGX660 may be of a similar spec for it's mic input although nowhere to be found. I think I tried a matching tranny with mine years ago and it did something to the mic freq response, but maybe if I find the time I'll give it another go.

A screen shot below of the user manual of an old PSR-740 also suggests a Lo-Z mic. The sidebar on the right side mentions an MZ106s which I found an image of and it does have an XLR connector.

I do have a few of those matching transformers around gathering dust that I used to use on old cassette multitrack machines :)
Click to expand...

Again, thanks Mark. I do not suggest the transformer as any kind of '"matching" device but to do two jobs which my son finds valuable.
1) It allows a long XLR cable because the mic is only unbalanced within some 300mm of the input jack.
2) There will be a voltage lift which will go some way to mitigate the low sensitivity of the dynamic mic and the noise level of the pre amp.

The actual input impedance of the mic pre is impossible to gauge Mark but your schematic shows a bias resistor of 100k. The (ever so welcome!) RFI stop components are going to lower that somewhat at high frequencies but, if the mic was 600Ohms out (a figure I have in my head) and the load was indeed 100k that would be a gain of ~22dB. even half that would go a long way to combat noise.

In anycase, OP needs to adapt from XLR to unbalanced jack, might as well get any benefit a traff can afford? https://cvp.com/pdf/behringer_xm855-spec-sheet.pdf

That ^ gives the impedance as 150 Ohms so the transformer will give an even greater voltage boost. However, the quoted sensitivity at 70dB/Pa is just plain wrong! I tested one side by side with a 57 and the Berry came out a touch louder. So, they can get THAT figure wrong, take Z with a drum of salt? Don't really matter...Impedance? Shimpeedance! All over the shop. Look up the numbers for the SM57/58 from various yeare and several figures are given, 150R, 300R and suggested loads of 1k or 600 Ohms. No matter, mics are 'Voltage matched' to a large degree and input impedance makes little difference.



Dave.
 
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BLOODY eyes!! Further magnification reveals that pre amp does NOT have a Z in anywhere near 100k! It is in fact a shunt feedback amplifier with a gain of 11 dB (nearly x4) and an input Z of 5k6 giving a potential lift of 15dB. Well worth having?

Dave.
 
IMO....complicating the decision making for no reason really. The evidence still seems to say that a decent dynamic that doesn't require more than normal gain...and there are MANY with excellent sound quality.... will work fine.....as others have already pointed out.

As always....just my 2 cents worth.

Mick
 
Mickster said:
IMO....complicating the decision making for no reason really. The evidence still seems to say that a decent dynamic that doesn't require more than normal gain...and there are MANY with excellent sound quality.... will work fine.....as others have already pointed out.

As always....just my 2 cents worth.

Mick
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No. Mark has already told us a dynamic mic is likely to be noisy.

Dave.
 
ecc83 said:
No. Mark has already told us a dynamic mic is likely to be noisy.

Dave.
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It will noisier with a low output mic like an SM57/58 (1.6mv/PA). Less noise and tolerable with a mic that has a higher output neodymium magnet that usually has a higher output (2.5-2.8mv/PA). While these keyboards can give a reasonably decent recording, it's not intended replace a good external preamp/interface and they work well as a sketchpad. Add some reverb and other onboard effects and you're good.
 
arcaxis said:
It will noisier with a low output mic like an SM57/58 (1.6mv/PA). Less noise and tolerable with a mic that has a higher output neodymium magnet that usually has a higher output (2.5-2.8mv/PA). While these keyboards can give a reasonably decent recording, it's not intended replace a good external preamp/interface and they work well as a sketchpad. Add some reverb and other onboard effects and you're good.
Click to expand...

Yes Mark and I would guess the Neo mics are quite expensive? The chap will STILL need to adapt from XLR balanced to TS unbalanced. Your comment that the keys are a bit naff compared to a decent AI (or mixer!) makes me even more inclined to say "buy the cheap but decent 8500 and the transformer".

Dave.
 
Neo mics aren't necessarily "quite expensive". CAD's TSM411, D90 and D92 mics use neodymium, and they run about $100 at list, but sell for much less. Sennheiser's 935 and 945 are neo mics. The 935 is $50 cheaper than the NT1a the OP already had and is planning to return. It also puts out 2.8mv/Pa, which is higher than the SM58.
 
TalismanRich said:
Neo mics aren't necessarily "quite expensive". CAD's TSM411, D90 and D92 mics use neodymium, and they run about $100 at list, but sell for much less. Sennheiser's 935 and 945 are neo mics. The 935 is $50 cheaper than the NT1a the OP already had and is planning to return. It also puts out 2.8mv/Pa, which is higher than the SM58.
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No well, I hadn't looked but my suggestion of the 8500 and transformers is even less at around $40 all up. And it keeps on being forgotten that any decent mic will terminate in XLR and need some form of adapter.

Dave.
 
The DGX660 is an $800(US) keyboard. Splurging on a decent mic that has a NEO magnet shouldn't break the bank and the 'adapter' can be simply a cable that ties the XLR pin 3 to ground at the 1/4" and the XLR Pin 2 is the 1/4" tip...... https://www.amazon.com/Hosa-PXF-105-XLR3F-Unbalanced-Interconnect/dp/B000068NYM or with some soldering skills cobble one together.

Someday the OP may get an interface or similar if he/she stays with the music journey. May as well have a decent mic to start with.

Dave, have you ever seen a correct sensitivity spec for the XM8500? Most everything I find just states -70dB. Not sure if this implies -70 dBv/PA or if they decided not to spec the mic like every other manufacturer does. I do have an XM1800 I got cheap on ebay an that is standardly specced at -52dB/PA (2.5mv/PA), so I was never sure where the -70dB figure came from for the XM8500 or if it was correct.
 
ecc83 said:
No well, I hadn't looked but my suggestion of the 8500 and transformers is even less at around $40 all up. And it keeps on being forgotten that any decent mic will terminate in XLR and need some form of adapter.

Dave.
Click to expand...

Hey Dave, I did a comparison using a cheapo Behr XM1800 mic with an XLR to 1/4" TS cable and then an XLR cable into an AT8201 matching transformer into my PSR-S900 keyboard. Using the matching transformer the mic seemed to lose some of its middle to bottom 'beefyness' and seemed a bit more 'toppy'. The levels were about the same with either the XLR to 1/4" TS or using the matching transformer as best I could judge using a single LED as a level indicator and my ears. Guess it could go either way, but I didn't care for what seemed like a shrillness with the matching tranny.
 
Mark,

The -70dB is the sensitivity rating in v/ubar. 1 Pascal =10 ubar

This is the rating on the Senn e935"
Sensitivity in free field, no load (1kHz)- 2.8mV/Pa = -51dB (0 dB = 1V/Pa) = -71 dB (0 dB = 1V/ubar)


If the Berry is rated at -70, then is is probably close to the same output of the Sennheiser.
 
TalismanRich said:
Mark,

The -70dB is the sensitivity rating in v/ubar. 1 Pascal =10 ubar

This is the rating on the Senn e935"
Sensitivity in free field, no load (1kHz)- 2.8mV/Pa = -51dB (0 dB = 1V/Pa) = -71 dB (0 dB = 1V/ubar)


If the Berry is rated at -70, then is is probably close to the same output of the Sennheiser.
Click to expand...

I wonder why they chose to spec it that way rather use what is more conventional that most everyone is familiar with?? :(
 
Its an old way of measuring sensitivity. Sometimes it was expressed as dynes/cm2 which is a ubar.

Here's a bit of an explanation and conversion page. It might be helpful to bookmark it since some other companies still use dyne/cm2 or ubar ratings.

Microphone sensitivity conversions
 
TalismanRich said:
Its an old way of measuring sensitivity. Sometimes it was expressed as dynes/cm2 which is a ubar.

Here's a bit of an explanation and conversion page. It might be helpful to bookmark it since some other companies still use dyne/cm2 or ubar ratings.

Microphone sensitivity conversions
Click to expand...

Yes, that explains it Rich. I shall read that link later but I do recall long ago, pre all this computer swaddlin, mics were specified at 75dB SPL at one foot which was judged to be the level genrated by male speech. Thus my RB ribbons delivered around 150 MICRO volts from an impedance of 50 Ohms.

Mark, the combination of the XM8500 and transformer is totally unknown from the sound quality point of view but, if the OP is coughing at the cost of 'better' mic then he should do ALL of the job properly and keep the LDC and get a mixer/pre amp!
If, on the other hand he just wants to get some vocals into his mix as a working start I am sure the XM and traff will do him just fine. Once he has the gear rigged and some experience under his belt he can look at 'fine tuning' his vocal sound.

Yes, he can just buy an XLR to TS plug cable but it is an added expense (I assume he already has an XLR-XLR cable?) AND a kludge and another one trick pony. 'King useless for much else. The bodge also offends the technician in me!

I don't know where OP lives but if reasonably close to UK I will put my MWMMIis and say "get the xm and traff and if you don't like it I will buy it off ya and ship it to son in France!"

Dave.
 
TalismanRich said:
Its an old way of measuring sensitivity. Sometimes it was expressed as dynes/cm2 which is a ubar.

Here's a bit of an explanation and conversion page. It might be helpful to bookmark it since some other companies still use dyne/cm2 or ubar ratings.

Microphone sensitivity conversions
Click to expand...

Somewhere back in the cobwebs of my aging brain cells I seem to recall some old mics I had back in the mid 60's that may have been specced that way. Lafayette Radio was a place I frequented back then and I found a catalog which among other fun stuff of the times had microphones and the screenshot below shows that old style old of expressing mic sensitivity.

Dave as well as anyone else from that era might enjoy browsing these catalogs I came across. My first reel to reel tape recorders were Lafayette branded. :D
LAFAYETTE CATALOGS: Lafayette Electronics and Concord Radio

There are even guitars, amps, and other musical instruments in these old catalogs :)

Pretty sure I had one of those $1.95 crystal mics.
 

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