low budget mic and speakers for conference calls

Special Interest Groups Recording Equipment
1

First of all, happy new year everyone, specially for those of you who might be thinking “look who’s back from the ashes” :wink:
I’ve missed you all :slight_smile:

I’m looking for a low budget solution for skype conference calls in a meetings room.
For some hidden reason this forum immediately pops up in my head when I think about buying audio equipment :stuck_out_tongue:

Room setup: fairly large rectangle room with horrible acoustics (lots of echo hehe), bunch of tables packed together in the center, chairs around it, empty walls.
Mic needed: omni mic to sit in the center and able to capture the voice of 5/6 people sitting around it.
Speakers: 2.0 speakers for listening to the person(s) talking on the other end of the skype calls and also occasionally to provide audio for some videos projected on the wall.

Today I did some tests on a skype call using a T.bone SC1100 connected to an ART USB Dual Preamp (usb connection to laptop) and some fairly old Creative Gigaworks T20 speakers.

Audio on the other end sounded wonderful (according to my testing mate).
Sound coming out of the speakers not so great, but I think mostly because the mic oh the other end was terrible (even with headphones I couldn’t hear it very clearly…).
Then we put the speakers on the other room and the sound coming from the T.bone (through skype) apparently was good enough to understand perfectly what I was saying.
I also had a quick go with a cardioid T.bone SC140 in place of the SC1100, but the results were not quite satisfying (as expected…).
BTW, using the built-in high-pass filter on the SC1100 was top-notch :wink:

Extra note: even with the speakers near the mic there was no echo, so it seems echo cancellation on skype works pretty well with decent equipment :wink: (not so true when you move to a crappy built-in mic/speakers on a windows laptop)

Anyway, back to business… t.bone + art preamp is completely out of budget, so I’m looking into a Snowball or Samson UB1, which are about the same price and still a bit over the budget I was given, but I don’t think I can go much lower without severely compromising the audio quality.
But if anyone has a better/cheaper alternative I’m listening :wink:
Also not sure between snowball and samson ub1, never had any of those… Any insight?
And will either be able to get anywhere near the results I achieved today with the t.bone sc1100+art preamp? Maybe better than with the sc140?

As for speakers, gigaworks T20 sound reasonable, but also slightly over the budget. Creative Inspire T10 and Logitech Z200 are both within the budget (nearly half the price of the T20), but not sure if it will have enough power to fill in the room (5 watts for T10 and Z200 vs 14 for T20).
For when the other skype caller has a crappy mic, maybe a software high pass filter could do some wonders… and make it audible on speakers.
Any other alternatives I could look into?

No fancy stuff, I need something fairly mainstream that I can buy in europe :wink:


Thanks in advance :wink:
Bruno

2

There are stand-alone audio conferencing units that were reasonably successful but I don’t remember enough about them. Flynwill may know.

They have the advantage of auto everything and they “know” the relationship between the speakers and microphone because they’re all in one package. One of the systems had a main and a satellite module for long conference room tables.

I just don’t remember enough about them…

Koz

3

The Polycom range is very popular in business:

http://www.polycom.com/voice-conferencing-solutions/conference-phones.html#phone-finder

They used to have an expert hotline. It can be worth your while to call them to ask about features.

You also need a quiet room and this setup isn’t usually what could be called low-cost as these phones start at about 200 $ going up to over a 1.000 $…

4

Thanks Koz and cyrano.

Polycom was one of the first hits I got when I googled for it. It looked interesting but also pricey and probably not that easy to get outside US.

This is for a small business that can’t afford that much. I was given a budget of 80-100 euros, though I’m trying to stretch it to 150 €.
Regarding the mic, I will talk to a local apple store next week and see if they have a snowball in stock that they can land for testing purposes…

Aesthetically the Samson UB1 would look better on the table, but I couldn’t find any review comparing it to the snowball and ordering it online will probably be my only option for getting my hands on one…

5

Hi bgravato, nice to hear from you again :slight_smile:

“Boundary mics” (also known as “PZM”) are generally a good choice for putting in the middle of a table with people sat around. I don’t know specific models in the cheap range, but they do exist. The Samson UB1 is of this type and Samson are a known brand with a reasonably good reputation for decent quality at budget prices, so if buying blind (without being able to hear it before buying) then I’d be tempted to give it a go. There are even cheaper models such as the “Alctron AL2002 USB Desktop Boundary Microphone” and “Studiospares SB450USB Boundary Mic” but I’ve not used them myself.

6

Try a PZM mic. These are usually the best to record groups.

The Audio-Technica ATR4697 is 34 € currently with thomann. The Superlux E303B is 39 €. Combined with an Alesis Core 1 interface you’re still below 100 €…

The Superlux has XLR connectors, the AT has a 3,5 mm jack, so you’ll need an adapter to XLR.

What makes these Polytronic phones so expensive, is the fact that they contain anti-feedback and echo cancellation circuits. These require a DSP and that’s not cheap.

7

We had a number of “chat 150” units from ClearOne at Koz’s and my previous employment. They are not cheap but did seem to work pretty well. They can be interconnected as a two-unit system for larger tables (but you need their cable kit, or buy the pair as the “chatattach 150”). As others have mentioned the biggest advantage of these units is the built in DSP that provides echo cancellation, and I believe some processing to “direct” the mic array towards whoever is speaking.

I’ve used Polycom units as well, but only the fully integrated IP speaker phones which I don’t think is what Bruno is after.

Generally there’s no good substitute for a room with well-damped acoustics. Hanging some tapestries (or even moving blankets) on the walls will make a big difference in the sound quality.

8

Now picture echo cancellation and network delays when two or three locations have bad rooms.

WHAT!! I CAN’T UNDERSTAND YOU!

Or worse yet:
I ___wonder if I and then if[gargle][gargle].

You can do “fake” Pressure Zone with regular microphones.

Attached-bottom is the final deployed form. That’s Hollywood Duvetyne on the bottom instead of the towel. Essentially black felt. The towel works and it’s there to keep table noises out of the show. It’s a Radio Shack 3013 microphone.

https://www.radioshack.com/products/tie-clip-mic?variant=5717723717

This is a Shure SM58 in full theater conference mode.

Koz
3013PressureZoneFinal2.jpg

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The SM58 is directional and you can aim it. The Radio Shack isn’t and is placed in the middle of the table.

Koz

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Thanks guys for all the suggestion I’m looking at them.
PMZ seems like the way to go :slight_smile:

It’s going to be used mainly by non-techies and I won’t be always around, hence why I was looking more for a simple usb “plug’n’play” type of mic, such as the samson ub1.
100€ budget was for mic + speakers, but I think I can stretch it a bit…

Audio-technica and superlux pmz’s look nice and are cheap (in price), but require an extra piece of equipment, so I’m still leaning towards a model with usb integrated (samson ub1 seems like the best candidate so far, 77 at thomann’s).

Echo cancellation might not be that crucial… skype’s software echo cancellation seems to work pretty fine with fairly decent equipment (that is, when the waveform coming in from the mic is fairly similar to what it’s sending to the speakers…)
My personal experience with skype tells me that it’s when there’s a lot of distortion on the speakers and/or mic, that skype’s echo cancellation goes down the drain…

11

How big is the room? USB has a length restriction. We had one conference room which required the wall-powered USB Hub trick half-way along between the conference room table and the actual computer. This effectively gives two USB cable restrictions end to end and it was enough for reliable operation.

6 feet, 2M? Something like that. You’re not connecting a mouse or keyboard where some error may be tolerable. You’re talking about a constant, perfect data connection. Also, cheap cables have shorter length restrictions.

Koz

12

A laptop will be sitting on the table near the mic. It will be used for the skype call and probably the laptop’s built-in camera might be used too (though quality of video is not important, only audio is).
So any 1m long usb cable (or whatever is the typical length of an usb cable) will do.

13

It will be used for the skype call

You said the magic words. Audacity and Skype do not get along on the same machine. It’s not fun when two dominant sound programs start battling over a single set of hardware resources.

We recommend software designed to “know” about Skype and how to deal with resource issues such as:

Pamela
http://www.pamela.biz/en/products/

And others:
https://forum.audacityteam.org/t/help-recording-with-a-mic-laptop-and-headphones/35068/6

Fair warning some packages do not split the near and far sound and some insist on exporting to MP3 instead of WAV. The upper two Pamela licenses, Professional and Business allow split recording and export to high-quality WAV.

Koz