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Re: Grounding Issue with TSB2590 #P48mems

 

Would it be worth a try if i connected the cable shielding to the ground of the capsule case? Or am I risking damaging something by doing so?


Re: Merging three Capsules on two Preamps?!

 

On Tue, Feb 11, 2025 at 10:29 AM, <martenberger92@...> wrote:
I am aware that in a way I am describing a mixer yes. But I want this setup to be as small and light-weighted as possible and also battery powered.
It still seems that your goals are in conflict:
  • XLR in with phantom power
  • high performance
  • mix controls or switching
  • small, lightweight, simple, portable, battery-powered
?
But anyway. Off the top of my head, a first approach to DIY might look like this:
  • crib some of the circuitry including opamp from the Opti-Alice project to buffer the raw capsules, to make one balanced mic preamp, and for post-mix makeup gain if necessary
  • battery supply (6v or more) from alkalines or rechargeables for the opamps
  • a charge pump, or 6x 9v (the rectangular PP3 type) for phantom power
besides I don't know any compact 3 channel XLR mixer with phantom power.
There are portable analog mixers available in the pro and semi-pro market. The Saramonic SR-PAX1 is a two-input mixer with phantom which might be a good starting point for modification, or combine two. Or their Smartrig+ mixer. I think Rolls offers similar mixers.
?
In the used market, the SHURE FP32 or FP33 can often be had for $200 or less. These are 3 mic in, stereo out, with phantom. Heavy little suckers.
?


Re: Merging three Capsules on two Preamps?!

 

No I want to Merge a Stereo AB with a Mono Mid/vocal mic.

I want to be able to switch between:

Stereo AB, Stereo AB + mono Mic, Mono Mic?

And if I can have some degree of balancing the mono mic with the stereo that be great too. Maybe just with an adjustable pad circuit.





Re: Merging three Capsules on two Preamps?!

 

Thanks for your view on this.

I have a Zoom, also a Sound Devices Mixpre10ii and many decent mics, so its not really about High fidelity or practicality here.
It's more about creating something playful and analog in nature just for the sake of it.

Yes I have been thinking also about using three electret capsules instead, too. However I would like the XLR input idea better.

I am aware that in a way I am describing a mixer yes. But I want this setup to be as small and light-weighted as possible and also battery powered.
besides I don't know any compact 3 channel XLR mixer with phantom power.
And the preamp quality of the tape recorder is really good, I dont want to decrease on quality...
Thats why I just want to switch between Stereo AB and Mid Mic or merge them.?
?
BTW: If you dont need your Sony walkman anymore, I'd happily take care of it and feed it with heartfelt music?


Re: Grounding Issue with TSB2590 #P48mems

 

Yes, but the case doesn't?connect to the circuit ground (Pin-1) of the XLR's. In my instructable I run it all the way up to shield?the inner?two wires of the Mogami cable. I am also making the three?terminal Capsule into a "two terminal" by connecting S and G (Source and Ground). I have not had issues with this method and have used the 2590 in multiple projects this way.?

Jules

On Tue, Feb 11, 2025 at 9:18?AM gerttreggertert223 via <gerttreggertert223=[email protected]> wrote:

They look to be shielded. ive attached a photo so you can see what im talking about.
They have Mesh in front and the body is soldered to ground on the 4 pads in the right picture. They should be grounded.



--
Best Regards,

Jules Ryckebusch

214 399 0931



Re: Grounding Issue with TSB2590 #P48mems

 

They look to be shielded. ive attached a photo so you can see what im talking about.
They have Mesh in front and the body is soldered to ground on the 4 pads in the right picture. They should be grounded.


Re: Alctron MA-1 Schematic question

 

S1 would allow you to disconnect the input at pin 2 (dont know why anyone would want that...), S2 selects an input impedance (~3150 ohms or 150 ohms).? The MA1 preamp is powered by +48v phantom from the following mic preamp it's plugged into. Phantom is not passed through to the MA1's input.


Re: Merging three Capsules on two Preamps?!

 

There's a way to make a passive battery box that could bias 3 electret capsules and has the "mono" capsule feeding both the L and R outputs, but it would have a bit of loss from a resistive mix matrix, and it wouldn't really have the blend control you wanted. And it wouldn't provide any XLR input(s) with phantom.
?
You could build a mini mixer with 3 XLR mic inputs; there are many balanced mic preamp circuits out there, including with phantom... but since you can buy decent little mixers for not much more than it would cost to DIY one it, it would seem pointless.
?
And all this effort to feed a cassette recorder? (hey, i have a SONY Walkman Pro cassette recorder somewhere, but it had its day, and we've moved on)
?
Your best move is probably to put your money into a new (or used) digital recorder that will record from 4 mics, so no external box or mixer required. A starting point would be ZOOM - such as their H4n Pro, H4E,? H5, or H6E recorders. Also Tascam.


Re: Merging three Capsules on two Preamps?!

 

You are describing a mixer. There are small ones out there that would accomplish?this. And as has been mentioned, take the two ambience capsules pan one hard right one hard left and mix the vocal in the middle. Adding them in mono may not sound good.

Jules

On Tue, Feb 11, 2025 at 7:27?AM martenberger92 via <martenberger92=[email protected]> wrote:

Hi all,
I would like to create a little circuit box that merges the signals of two ambient mics (L/R) with a single vocal mic (M) before entering the preamps.
So I can record stereo ambient and vocal simultaneously on my sony cassette 2 Track cassette recorder.
The recorder has two decent mic preamps without phantom power.
Is that possible? How would a circuit like this look like?

I was thinking of using two omni primo capsules for ambient and a XLR input for the extra vocal input (potentially condenser +48V).

Ideally there would be a single switch or potentiometer with which I can switch from only ambient, to only vocal mic, and some in between settings.

Is there someone that could help me out with a circuit sketch??

And what would be the easiest way to add phantom power to that device? The whole rig is intended to be used in the field and with batteries.
I could install 9V block batteries or also 3,7V Lipo batteries as power supply.

Any help is greatly appreciated!

Thanks?
M



--
Best Regards,

Jules Ryckebusch

214 399 0931



Re: Merging three Capsules on two Preamps?!

 

Merging two omnis down to mono might not sound that great. They generally don't downmix to mono very nicely.?

J

On Tue, 11 Feb 2025 at 13:27, martenberger92 via <martenberger92=[email protected]> wrote:
Hi all,
I would like to create a little circuit box that merges the signals of two ambient mics (L/R) with a single vocal mic (M) before entering the preamps.
So I can record stereo ambient and vocal simultaneously on my sony cassette 2 Track cassette recorder.
The recorder has two decent mic preamps without phantom power.
Is that possible? How would a circuit like this look like?

I was thinking of using two omni primo capsules for ambient and a XLR input for the extra vocal input (potentially condenser +48V).

Ideally there would be a single switch or potentiometer with which I can switch from only ambient, to only vocal mic, and some in between settings.

Is there someone that could help me out with a circuit sketch??

And what would be the easiest way to add phantom power to that device? The whole rig is intended to be used in the field and with batteries.
I could install 9V block batteries or also 3,7V Lipo batteries as power supply.

Any help is greatly appreciated!

Thanks?
M



--

07889727365

02036861372

3 Swimmers Lane
Haggerston
London
E2 8FR






Merging three Capsules on two Preamps?!

 

Hi all,
I would like to create a little circuit box that merges the signals of two ambient mics (L/R) with a single vocal mic (M) before entering the preamps.
So I can record stereo ambient and vocal simultaneously on my sony cassette 2 Track cassette recorder.
The recorder has two decent mic preamps without phantom power.
Is that possible? How would a circuit like this look like?

I was thinking of using two omni primo capsules for ambient and a XLR input for the extra vocal input (potentially condenser +48V).

Ideally there would be a single switch or potentiometer with which I can switch from only ambient, to only vocal mic, and some in between settings.

Is there someone that could help me out with a circuit sketch??

And what would be the easiest way to add phantom power to that device? The whole rig is intended to be used in the field and with batteries.
I could install 9V block batteries or also 3,7V Lipo batteries as power supply.

Any help is greatly appreciated!

Thanks?
M


Alctron MA-1 Schematic question

 

I've recently seen the schematic for the Alctron MA-1. However, there are a couple of features that aren't clear and I hope to get some help from the group.
?
On the input side, after XLR1, there are two items labeled S1 and S2. They look like switches. S1 could be a mute switch. S2 looks like it connects XLR1-3 to either R1 or R2, perhaps to compensate for mic Zin.?
?
The other question I have is: where is power applied? Alctron's literature says it "operates on 48V, but does not pass phantom power to the mic." OK, but where is the power applied??
?
Dan


Re: Grounding Issue with TSB2590 #P48mems

 

¿ªÔÆÌåÓý

Aah, OK! So the buzz is due to teh fact that the capsules are not properly shielded.

The shield must extend as far as possible to cover most of the capsule. Ideally, even the front of the capsule should be shieded. Of course, a mesh should be used, to allow sund to hit the diaphragm.

Le 11/02/2025 ¨¤ 07:08, gerttreggertert223 via groups.io a ¨¦crit?:

They work great except for the buzzing. Im just using a simple p48 circuit so 1 3.3uF cap and a 100k resistor on the xlr plug.


Re: Grounding Issue with TSB2590 #P48mems

 

They work great except for the buzzing. Im just using a simple p48 circuit so 1 3.3uF cap and a 100k resistor on the xlr plug.


Re: Grounding Issue with TSB2590 #P48mems

 

¿ªÔÆÌåÓý

The one on the left is a 3-wire capsule, when the one on the right is a 2-wire.Depending on the circuit, they may be incompatible.
Apart from the buzz, does it work?

Le 11/02/2025 ¨¤ 03:45, gerttreggertert223 via groups.io a ¨¦crit?:

Maybe this is helpful. Ive attached both circuits of the datasheets of the capsules. On the left is the JLI2590a and on the right is the dr2501 I used. They look a bit different.?
Should i adjust the wiring?
?
?


Re: Grounding Issue with TSB2590 #P48mems

 

Maybe this is helpful. Ive attached both circuits of the datasheets of the capsules. On the left is the JLI2590a and on the right is the dr2501 I used. They look a bit different.?
Should i adjust the wiring?
?
?


Re: Grounding Issue with TSB2590 #P48mems

 

The capsules themselves are properly isolated from one another. They also look the same as the originals and i doubt they would go through the steps to make a fake of the tsb2590s. I think they just come out of the same factory under a different name to sell them on other places.?
Is there a way I can reduce the voltage potential the capsules float at? Maybe by adding another cap somewhere? Im not an electrical engineer and honestly dont know what to google for in this situation.?

Thanks for your help :D


Re: Grounding Issue with TSB2590 #P48mems

 

¿ªÔÆÌåÓý

I use the shield but only connect it to ground at the XLR. The capsules float at potential above ground and each one is a bit different. They need to be insulated from each other and handling. Also ¡°real¡± TSB2590¡¯s and I think the Primos have small internal 30pF or so for EMI Protection.?

Best Regards,

Jules Ryckebusch?

On Feb 10, 2025, at 19:13, gerttreggertert223 via groups.io <gerttreggertert223@...> wrote:

?
So ive built an Ambi-Alice based on the Instructable by Jules and used em272 capsules. I noticed my mistake (that these are omni and not cardiod capsules) and ordered some TSB2590 knockoffs off of ali. They arrived and sound fine but I get a weird electrical buzzing sound wich gets amplified if i touch the capsules, so i suspect it could be a grounding issue.?
I used 4.7uF Capacitors and 100k ohm resistors for the simple p48 circuit wich worked great with the em272s and should also work fine with the new capsules right?
Is there a way to fix this??
The instructable doesnt use the cable shielding connected to the microphone capsule, could this help or am i gonna destroy the mics by doing that?

Any help would be appreciated :D


Re: TSB2590 alternative?

 

Sorry I Just came across your Message now. Ive got them installed but having a bit of a problem with them as I described in another post :/ If im not able to fix the issue id gladly come back to your offer tho :)


Grounding Issue with TSB2590 #P48mems

 

So ive built an Ambi-Alice based on the Instructable by Jules and used em272 capsules. I noticed my mistake (that these are omni and not cardiod capsules) and ordered some TSB2590 knockoffs off of ali. They arrived and sound fine but I get a weird electrical buzzing sound wich gets amplified if i touch the capsules, so i suspect it could be a grounding issue.?
I used 4.7uF Capacitors and 100k ohm resistors for the simple p48 circuit wich worked great with the em272s and should also work fine with the new capsules right?
Is there a way to fix this??
The instructable doesnt use the cable shielding connected to the microphone capsule, could this help or am i gonna destroy the mics by doing that?

Any help would be appreciated :D