av Calleberg » 2022-01-03 12:23
Där ser man och som vanligt kunde man listat ut det i förväg om man läst "rätt" recensioner på thomann.
En trestjärnig översatt från tyska:
It could have been so nice: Buy three of them and equalize a 12-channel control for less than 250 euros: set delays, some EQ and good.
Unfortunately, I cannot recommend this product and I had to send it back.
The positive aspects can already be found in other reviews and I can only agree with them. The DSP works and I don't mean to say that there aren't use cases where it does exactly what you need. The size is great and you can mount three pieces next to each other on a rack tub (Thon Rack Adapter 1U 25) if you let the side tabs overlap (of course you have to drill the right holes in the rack tub). Incidentally, the boxes included USB cables and a power supply in the delivery, but Thomann still sent USB cables and power supplies separately.
But:
(The measurements described were made with the Room EQ Wizard on an RME Babyface; the absolute levels were calibrated with an oscilloscope and corresponded fairly exactly to the level data from the Babyface data sheet.)
1. Sound
- The data sheet specifies 105 dB SNR. I can approximately confirm this figure at full level (mean value 105 dB up to approx. 4 kHz, then deterioration up to 95 dB @ 20kHz). However, the internal noise of the device is unfortunately by no means neutral, but has peaks at 2 kHz, 4 kHz, 6 kHz etc. The level of these peaks is up to 13 dB above the even noise floor. This is noticeable (if the USB cable is NOT connected) as a quiet but annoying buzz. The buzzing becomes significantly louder when there is a USB connection to the PC.
2. Distortion
- The level working range that can be used sensibly is severely limited. With understeering, the buzzing is more important, with oversteering, of course, the distortion. What I resent: The +12 dBu at 0 dBFS given in the data sheet (already tightly measured) are simply wrong. My guess: when creating the data sheet, you may have measured with unbalanced connections. Unbalanced I also get about +12 dBu permissible input level. With a symmetrical connection, the automatically available 6 dB gain means that the modulation limit is already reached at approx. +6 dBu (!).
- If everything in the device is set to "Bypass" (more on this below), the signal at the output is approx. 2 dB louder than at the input.
Table showing when distortion occurs at the output:
Input symm. [dBu] ..... Selected output gain within DSP ..... Output symm. [dBu] ..... distortion
+6 ....- 1 ... + 7 ... ok
+6 ..... 0 ... + 8 ... ok
+6 ... + 1 ... + 9 ... distortion @ <150 Hz
+6 ... + 2 .. + 10 ... broadband distortion
Table showing when distortion occurs at the input:
Input symm. [dBu] ..... Selected gain within DSP output symm. [dBu] ..... distortion
+6 ...- 10 ...- 2 ... ok
+7 ...- 10 ...- 1 ... Distortion @ <200 Hz
+8 ...- 10 .... 0 ... broadband distortion
3. Metering
- The metering displays in the control software have already been described in another assessment and the level values have also been measured. In practice it is important that the metering does not offer any protection against overload. The overload LEDs in the software are not working. So you have to make the narrow work area even narrower yourself or accept to have an over now and then ...
4. Usability
In my application I wanted to use three devices of the same type to control a 12-channel monitor. There is no option in the software to select a specific device from several devices that are connected at the same time. The "first" what the software sees is taken. As an emergency solution, you can deactivate / activate the individual USB ports in Windows so that the software can only discover a single device. It's just a shame that the devices do not also transmit a serial number (as is actually intended in the USB standard ...). The three devices look exactly the same in the device manager and you can only guess or write down which device is connected to which port and how the port is designated in the device manager. It is helpful that you can name the DSP presets so that you can tell which device is currently online. But practical is different.
5. No global bypass
In my application, compression and limiters are prohibited. I have to be able to judge what can actually be heard on the recording, not what my equalization might change dynamically.
Unfortunately, there is no way to completely deactivate functions such as the compressor or the limiter. That worries me, because who can guarantee that the compressor won't work secretly just because I have the threshold set to 0 dB? At the same time, the device doesn't show the internal level (see above), so I don't even know whether the device "thinks" it should compress.
All in all: sent back. Fortunately, Thomann's apprenticeship only applies to the time that has been spent on it. Now a Symetrix Prism has to work.
