Cheap Audio Measurement Gear

[watchnerd]

Check the specs for distortion of sine signals and frequency precision.

Output Characteristics:
Amplitude resolution: 1mV
Amplitude stability: ±0.5%/5 h
Amplitude flatness: ±5%(<10MHz); ±10%(>10MHz)

 

[KaMiKaZeCATS]

Almost forgot about this thread.

In the time I started this I have purchased a owon osiliscope and I will be buying a uni-t function generator and the QA401

The owon osiliscope is model XDS3102AP 100MHz, 1GSa/s, 2ch, max 14bits ADC, 75000wfms/s refresh rate. I just paid for this today and will be getting it next week.

I will most likely be purchasing the QA401 as my audio anaylzer.

For my function generator I found a used one locally that has 0.2% distortion in the audio range and its 60mhz for about 100 usd. I'm still looking around and will update this thread once I get everything.

Please don't take any of these as recommendations since I haven't received anything yet.

I may post some reviews of some cheap ess dacs from China although I'm am unsure if I will do this. I plan to make some amplifier circuits for sale. But we shall see how things work out.

At this time I am also looking for some nice low ripple cheap bench power supplies so any recommendations would be welcome. I'm already aware of the RD tech ones but they have quite a bit of ripple. But they may have to do.

 

[KaMiKaZeCATS]

Output Characteristics:
Amplitude resolution: 1mV
Amplitude stability: ±0.5%/5 h
Amplitude flatness: ±5%(<10MHz); ±10%(>10MHz)

So "Koolertron" is the Western overpriced reseller of JUNTEK.

Firstly, For the one you posted, the "real" model number is JDS6600. You just Google that and you can see its the exact same.

Secondly, don't buy it from amazon, get it from the source, aliexpess. https://m.aliexpress.com/item/4000442964873.html?spm=a2g0n.productlist.0.0.2bc5110bYqGux3

It's only 60 USD for the 60 mhz version.
Secondly the specs you listed is not distortion. Rather it's frequency response. This is distortion:

Sine - Total harmonic distortion: <0.8%(20 Hz~20 kHz,0dBm)

From aliexpess link.

Hope this helps you!

 

[sergeauckland]

Unless you're going to be doing 'proper' development work, for home 'hobby' use and general maintenance, I have a lot of time for older analogue instruments from various manufacturers.

My own workshop has signal generators from Levell and Ferrograph, metering from Levell and Ferrograph, 'scope from Hitachi, RF generator from Boomton Radio, and various analogue and digital multimeters.

I can measure down to 0.01% distortion (ish) which I see as quite good enough to judge whether the device is OK or faulty, whatever the spec may say. Ditto with frequency response up to 100kHz, and noise down to -100dBu. I also use a PC with REW, ARTA, RMAA on it which gives me FFT capabilities the analogue instruments don't, but then they give me a visual of the distortion residual which an FFT won't.

Equipping a home workshop with instruments such as I have will probably only cost a few hundred £$€ from eBay, and as long as the instrument works, it's usually Good Enough for the purpose.

Clearly, if I were a manufacturer or reviewer, then my instrumentation would have to be rather better and regularly calibrated as I would be verifying manufacturers' claims or indeed my own claims, so would need to be unimpeachable, but for home use, I don't see an issue with uncalibrated equipment as long as it works well and consistently.

S

 

[watchnerd]

So "Koolertron" is the Western overpriced reseller of JUNTEK.

Firstly, For the one you posted, the "real" model number is JDS6600. You just Google that and you can see its the exact same.

Secondly, don't buy it from amazon, get it from the source, aliexpess. https://m.aliexpress.com/item/4000442964873.html?spm=a2g0n.productlist.0.0.2bc5110bYqGux3

It's only 60 USD for the 60 mhz version.
Secondly the specs you listed is not distortion. Rather it's frequency response. This is distortion:

Sine - Total harmonic distortion: <0.8%(20 Hz~20 kHz,0dBm)

From aliexpess link.

Hope this helps you!

Thanks, although I think I'm going to invest in something better.

The B&K and Siglent models have lower THD by an order of magnitude.

 

[watchnerd]

You do no need more than this DLock USB Dac and Sdif output

https://www.delock.com/produkte/S_63926/merkmale.html 30-40 usd

a 2usd optical cable mini type, and free REW software, and Umik microphone

I got the Focusrite Sol gen3 but do not use it anymore, it gives too inconsistent results,,,and does not measure better than the Dlock

I got a Siglent 1202X-E oscilloscope. I am happy with it ,does all I need and reasonable price. See reviews on You

tube

What probes are you using?

Just the ones that came with the unit?