Loudspeaker Testing Equipment

[bwhitejr]

I have been busy raising kids and have been away for a while.
What is everyone using to test loudspeakers these days? I see digital spectrum analyzers (USB) and others that have sound cards and analysis software.

bwhitejr

[Ouroboros]

I use ARTA for this purpose at work. It is a program that provides a lot for your money! (read the manuals well first though!)

I suggest that before you use this (or any other similar program) that you download RMAA and check your soundcard first. A lot of sound cards using Y5V dielectric output capacitors show high distortion at low frequencies. The built-in sound on some of the Mini-ITX boards from VIA measure adequately at the normal distortion test frequency of 1kHz, but are much worse at 100Hz for example.

[gtforme00]

I still use good odd, err I mean old, Speaker Workshop. See Claudio Negro's website for condensed instructions.

Mic is homemade from a panasonic electret (WM60a for me), and homemade preamp ala Eric Wallin. http://mysite.verizon.net/tammie_eri...mp/preamp.html

Checking your soundcard is essential as recommended above. Good soundcards for Speaker Workshop are cheap, see Claudio's list of older soundcards that work fine. 16bit 48kHz is fine for the casual user.

Total cost for me was around $30 with resourceful use of stashed parts.

Regards,
David

[bwhitejr]

Are there any USB cards capable of high resolution like 12 bit and above?

bwhitejr

[Svante]

Originally posted by bwhitejr
Are there any USB cards capable of high resolution like 12 bit and above?

bwhitejr

Oh yes...

You can find many "24-bit" USB cards, however the best have a SNR corresponding to 20 bits or so.

[gtforme00]

Funny you should ask. I've been comparing them myself for my laptop. Keep in mind I don't own any of these products, but have been trying to exercise due diligence by searching extensively for other's experience with them before I purchase.

I am using a separate microphone preamp that I built as stated in a previous post, although alot of people buy the Behringer ECM8000 these days. If you use this microphone, you must use a balanced input preamp with +15 to +48 V phantom voltage. Some soundcards have this built-in.

Mind you that Speaker Workshop only works at 16bit resolution. Speaker Workshop also requires full duplex operation. Some soundcards will not operate at their highest sample rate if used at 16bit resolution or in full duplex mode. I will list the highest mode for each soundcard that is compatible with Speaker Workshop.

ARTA works with up to 32bit resolution I believe.

In order of my impression of their performance here are a few I have been considering.

EMU 0404 : Up to 24bit - 192kHz Full Duplex claimed. 48V phantom power and balanced input. EMU told me that it will operate at 16bit-192kHz Full Duplex, it is not explicity listed in the datasheet however. 113dB Mic-In SNR, MSRP $199

EMU 0202 : Up to 24bit -192kHz Full Duplex claimed. Similar to 0404, but without the phantom power. EMU told me that it will operate at 16bit-192kHz Full Duplex, it is not explicity listed in the datasheet however. 113 dB Mic-In SNR, MSRP $129.99

M-Audio Mobile Pre : Up to 16bit - 48kHz Full Duplex. 48V phantom power and balanced input91 dB Mic-In SNR, MSRP $179.99

Edirol UA-1EX : 24bit - 48kHz Full duplex. 16bit - 48kHz Full duplex. RCA inputs as well as mini jack. SNR not available. MSRP $99

M-Audio Transit : 24bit - 48kHz Full duplex. 16bit - 48kHz Full duplex. Mini jack inputs. 100dB Mic-In SNR, MSRP $99

For a budget application, the Edirol UA-1EX is typically available for around $80 and represents a good value IMO.

The 0202 would be my choice for best performance/price at a typical price of $110.

Either of these have a condenser mic input which would work with an electret mic (i.e. WM61A). This electret has generic calibration curves available and should be fine for amatuer needs. If you need the balanced input and phantom power, then I would choose the 0404.

Please keep in mind that these are my preferences based on an objective search to suit my own needs. I have no interest in recommending one sound card over the other and do not hold any allegiance to a particular manufacturer. If there is a better soundcard for the money out there, I would love to know about it in an equally objective manner as the one presented here.

Best Regards,
David

[athos56]

I just got a Phonic Paa2 handheld RTA off of e-pay for ~200 and some change. Don't need a computer or separate mic, got my home system pretty flat, and worked out some room nasties... It was also helpful in making a notch filter for my co-axials. Best part is the learning curve is a nothing...
Athos

[johngalt47]

For just checking the T/S parameters, I bought a model 72-850 from Tenma. Call me at work if you want to borrow it.
Ren