Very basic question on powering ribbon mics----?

[halfred]

I'm sure this an easy one for most of you recording folks. I'm considering trying out a pair of ribbon mics for my home recioding of acoustic piano. I'm interested in, for one, a sonotronics Apollo which requires 48v phantom power, or the Cascade X-15 possibly which operates on a transformer. Hadn't realized prior that many ribbons do not require phantom power. So, I'm assuming since the Cascade and many others have transformers, that the power is directly from the transformer--duh--right? So you just plug the mics into your preamps, and the mics just have "on' switches? Some of the mics I'm considering have transformers, others use phantom power. My other question is, how does transformer powered vs. phantom powered impact the sound of the recordings--is there a difference? Is that what is meant . passive ribbons as opposed to active riboons, the active ribbons meaning they require phantom power?

 

[RawDepth]

You are correct. Passive ribbons do not require any power. They function as a dynamic mic. The moving ribbon generates ac voltage. The transformer (also passive) simply increases the voltage and lowers the ohm load. They don't have any switches.

In an active ribbon design, I believe the phantom powers a small preamp circuit inside the mic.

 

[halfred]

You are correct. Passive ribbons do not require any power. They function as a dynamic mic. The moving ribbon generates ac voltage. The transformer (also passive) simply increases the voltage and lowers the ohm load. They don't have any switches.

In an active ribbon design, I believe the phantom powers a small preamp circuit inside the mic.

Ok, so you mean they respond to sound all the time? If no switches, how are they turned on and off (I'm not familiar with dynamic mics, have only used condensers so far---)

 

[Jim Lad]

You are correct. Passive ribbons do not require any power. They function as a dynamic mic. The moving ribbon generates ac voltage. The transformer (also passive) simply increases the voltage and lowers the ohm load. They don't have any switches.

Add to that.... I have a pair of Nady RSM 2, ribbons, a Nady RSM 5 ribbon, a Nady RSM8A (the A is for "Active) and a Golden Age R1 mkII active ribbon microphone.
The passive, ribbon microphones require about 80dB of clean gain in order to record them comfortably. As most audio interfaces and stand alones deliver a bit less than this, I have come to the conclusion that an extra preamp is pretty well necessary.
My RSM 8A just arrived and I am in the midst of setting it up. Even with the extra boost (about 40dB) that comes with the active ribbons, I am finding better results if I use a preamp.
The jury is still out for me regarding whether or not the active ribbons have improved the sound. I am extremely fond of the RSM 2s and haven't really tested them since I got the preamps.
Here are some links.
The microphones
http://www.wwbw.com/Nady-RSM-8A-Ribbon-Microphone-580009-i1432648.wwbw?source=ZTEM8XOC
http://pro-audio.musiciansfriend.co...275557&src=3WFRWXX&ZYXSEM=0&CAWELAID=26021026
http://pro-audio.musiciansfriend.co...277401&src=3WFRWXX&ZYXSEM=0&CAWELAID=26021230
http://www.recording-microphones.co.uk/Budget-ribbon-microphone.shtml
The preamps
http://pro-audio.musiciansfriend.com/product/Nady-PRA8-Mic-Preamp?sku=185277
http://www.zzounds.com/a--2676837/item--BEHADA8000
Both of these preamps only arrived in the last few weeks, by the way and I haven't really put them through their paces but in a wee test a couple of hours ago, the Nady outperformed the Behringer. Mind you, the Behringer's primary function is as a digital converter. i.e. it adds another 8 channels to my soundcard. Both are excellent buys.

 

[halfred]

Add to that.... I have a pair of Nady RSM 2, ribbons, a Nady RSM 5 ribbon, a Nady RSM8A (the A is for "Active) and a Golden Age R1 mkII active ribbon microphone.
The passive, ribbon microphones require about 80dB of clean gain in order to record them comfortably. As most audio interfaces and stand alones deliver a bit less than this, I have come to the conclusion that an extra preamp is pretty well necessary.
My RSM 8A just arrived and I am in the midst of setting it up. Even with the extra boost (about 40dB) that comes with the active ribbons, I am finding better results if I use a preamp.
The jury is still out for me regarding whether or not the active ribbons have improved the sound. I am extremely fond of the RSM 2s and haven't really tested them since I got the preamps.
Here are some links.
The microphones
http://www.wwbw.com/Nady-RSM-8A-Ribbon-Microphone-580009-i1432648.wwbw?source=ZTEM8XOC
http://pro-audio.musiciansfriend.co...275557&src=3WFRWXX&ZYXSEM=0&CAWELAID=26021026
http://pro-audio.musiciansfriend.co...277401&src=3WFRWXX&ZYXSEM=0&CAWELAID=26021230
http://www.recording-microphones.co.uk/Budget-ribbon-microphone.shtml
The preamps
http://pro-audio.musiciansfriend.com/product/Nady-PRA8-Mic-Preamp?sku=185277
http://www.zzounds.com/a--2676837/item--BEHADA8000
Both of these preamps only arrived in the last few weeks, by the way and I haven't really put them through their paces but in a wee test a couple of hours ago, the Nady outperformed the Behringer. Mind you, the Behringer's primary function is as a digital converter. i.e. it adds another 8 channels to my soundcard. Both are excellent buys.

Thanks, very helpful.

 

[RawDepth]

Ok, so you mean they respond to sound all the time? If no switches, how are they turned on and off (I'm not familiar with dynamic mics, have only used condensers so far---)

Yep. They are on when you plug in the mic cable and turn up the preamp. When you unplug them the ac from the mic stops flowing because the circuit is broken.

Ribbon mics are very sensitive to moving air. Never blow directly into one. Always use a pop filter/shield. Since the ribbon is so thin, you must protect them from wind even while carrying them across the room. Get into the habit of un-boxing and re-boxing it right at the mic stand every time.

 

[RawDepth]

...The passive, ribbon microphones require about 80dB of clean gain in order to record them comfortably. As most audio interfaces and stand alones deliver a bit less than this, I have come to the conclusion that an extra preamp is pretty well necessary...

That all depends on how loud the instrument is and how the mic is used. I've used ribbons on very loud sources and had too much signal even with the preamp turned all the way down. You only need a lot of gain for soft sources. That is when the noise floor (hiss) comes up to ruin the track. Many mic preamps tend to be noisy when pushed hard.

 

[Jim Lad]

That all depends on how loud the instrument is and how the mic is used. I've used ribbons on very loud sources and had too much signal even with the preamp turned all the way down. You only need a lot of gain for soft sources. That is when the noise floor (hiss) comes up to ruin the track. Many mic preamps tend to be noisy when pushed hard.

I use them for Vocals and Tenor Guitar so the noise floor is always an issue for me.

My RSM 8A just arrived and I am in the midst of setting it up. Even with the extra boost (about 40dB) that comes with the active ribbons, I am finding better results if I use a preamp.

Since posting that, I just spent a couple of hours on the RSM 8A and the Golden age with the Nady preamp running into the Korg D3200.
I jogged between the preamps on both until I had the levels just right. Then I plugged them straight into the Korg and got better results in seconds.
So two things...... 1) The active ribbon mics will run as well as a condenser without the need for additional preamps & 2) I'd say that adding a preamp to the line increases the risk of added noise so if you don't really need it, don't do it.

 

[dgatwood]

Ok, so you mean they respond to sound all the time? If no switches, how are they turned on and off (I'm not familiar with dynamic mics, have only used condensers so far---)

Most mics designed for recording don't have off switches. You turn them off by disabling recording for that track in your audio software or by muting it on the mixer if you have a hardware mixer or....

In general, if it has an off switch, it was probably designed more for stage use than for recording. (The obvious exception is any microphone with a built-in battery. Even if designed for recording, those generally have off switches so that you don't run down the battery when not in use.) I can't think of a single microphone in my arsenal with an off switch on the mic except for dynamic mics (and even then, only the ones that are designed for handheld use).

 

[halfred]

Most mics designed for recording don't have off switches. You turn them off by disabling recording for that track in your audio software or by muting it on the mixer if you have a hardware mixer or....

In general, if it has an off switch, it was probably designed more for stage use than for recording. (The obvious exception is any microphone with a built-in battery. Even if designed for recording, those generally have off switches so that you don't run down the battery when not in use.) I can't think of a single microphone in my arsenal with an off switch on the mic except for dynamic mics (and even then, only the ones that are designed for handheld use).

OK, looks like I'll be picking up Sonotronics Apollo which takes 48v phantom power like the condenser mics I'm used to using. So I won't be ordering the ribbons with transformers. Hard to understand stuff without having hands on experience.