Metric Halo +DSP MIO Tips, Tricks, and Tweaks
Tips, Tricks, Tweaks, for Metric Halo Mobile IO MIO hardware.
The ULN/LIO converters sound better, but they unfortunately introduce slightly more latency. 2882: A/D 39 samples, D/A 28 samples LIO-8: A/D 63 samples, D/A 44 samples So, at any given buffer setting, I believe the LIO will have 40 samples more latency than the 2882 (about .9ms at 44.1k). Thanks James.
There are two rules to box mapping, and if you understand them, it is not a problem to remap: 1) If you connect a box while MIO Console is running, it will be mapped to its own serial number in the console (if it exists) or it will get a new tab. 2) If a…
The DI path is DC coupled and single-ended. This means that it will gain up any DC present on the input signal; if the DC offset is too high at the converter, it will mute.
Termination is not needed when connecting a Master Word Clock sync to the MIO’s. The MIO’s should not be daisy chained in this case; they are internally terminated. They are AC-coupled, however, so the source will not see the 75- ohm to ground. So if the master clock has a termination indicator will not turn…
Before the 2d Enhanced MIO, MH was using the ADSP-21065L SHARC. When they designed the 2d card, they chose the ADSP-21364 family that is 5x faster and runs compatible code.
All original 2882’s shipped with solid steel top and bottom panels. Starting at serial #800, they were switched to aluminum. Older serial 2882’s can be upgraded to the newer aluminum panels through the MH shop. The unit must be sent back to Metric Halo as replacing the bottom panel necessitates re-mounting the PCB’s. The top…
the ULN8 and LIO both set the AES bit flag to Consumer on output. This can cause trouble with limited devices that only accept the professional bit flag for input. the ULN8/LIO accepts any valid AES input regardless of of flag status. The ULN2 and 2882 both mirror whatever bit-flags are sent to it. It…
jumper position J7 on the PSU board (by the power switch connector) bypasses the front panel power switch.
The legacy SHARC chips run up to 66 MHz, and have 68 KB of internal memory plus 8 MB of external very fast memory. The SHARC chips in the Expanded 2D system run up to 333 MHz and have 375 KB of internal memory.
The pan law on the MIO Hardware is “-3dB”. Also known as “Equal Power”. Hard panned channels are unattenuated. Center pan channels are attenuated by -3dB and sent to both left and right. Attenuation in the left output channel varies smoothly from 0dB (hard left) to -3dB (center) to -∞ (hard right) via a cosine…
For larger recordings, You’ll gain more disk I/O by disabling Spotlight. the Spotlight indexing has a substantial negative effect on disk write throughput. So, either disable Spotlight entirely, or add the Record drive (or even folder) into the Spotlight privacy list so that Spotlight does not try to index while you are recording…. Another good…
On the 2882, the offset is done in the digital domain. You can adjust the output trim BEFORE you put the outputs into monitor control, and it will use that analog gain as the basis point for the maximum output level. On the ULN-2, all monitor controller gain is in the digital domain, but you…
Are you using different components than you have traditionally? B.J. Buchalter: Not really, although the components of the types that we have been using continue to evolve and we continually evaluate new products to see if they fit with upgrades or new designs. what are they and in what areas are you seeing improvement (ease…
Metric Halo LIO-8 was released on 03/25/10 stands for Line In Out (as opposed to MIO Mobile In Out) It is a lower cost option to the ULN-8 and was achieved by removing the ULN-R (remote) preamps, and removing the +DSP license. Both of these options can be added at any-time as field upgrades, and…
————[MIO Disassembly]————- To Disassemble your MIO you will need a torx15 wrench or allen key that shipped with the unit. There is a very good disassembly video for 2882 and ULN2 by Travis Greg. ULN8 has 12 Philips screws of all the same size securing it’s case. When replacing the case, be sure to line…
————[MIO Inside]————- Now for the fun stuff 😉 2882+DSP w/ 2D upgrade card Legacy ULN-2 with original bridge board ULN-8 with 2D AES board Data sheets for the ADC and DAC chips are further down the page under MIO Conversion.
————[Flash Firmware]————- A very good step-by-step install tutorial is available in Metric Halo Tech Notes The install process is the same for all versions ( V1-5). You must be plugged into AC power for this to work. Current firmware files are located at MH Labs. In the MIO Console App choose Utilities > Update Firmware
————[Reset and Service Menues]————- There’s a second, alternative boot state on the 2882 that you can boot into if you press and hold the [mute] button when the box starts up. This alternative boot state is saved in the “Snapshot 1” state slot. If there in nothing saved in this slot, the alternate bootstate will…
————[Erase Boot_State]————- Use the following to clear your bootstate and start again with the default setup in V5:Navigate on your user drive to Library/Preferences, and delete the MIO Console Preferences folder, as well as any MIOConsoleStatev2. . . files below it. Empty the trash. Then with the MIO connected, double click the erasebootstate tool after…
———-[Mobile IO Clock]———– The old clock could be up to 50 ppm or so in practice(and it is actually only spec’ed to 100ppm) off in frequency accuracy. The new 2D clock is speced to +/- 10ppm and in practice is generally within +/- 5ppm. The Legacy clock had higher intrinsic jitter at 44.1k than at…
———-[Mobile IO Conversion]———– The MIO series uses Asahi Kasei (AKM) converter chips. The AKM 5383 is a 108 kHz 24-bit ADC, used in both the ULN2 and 2882 The AKM 4393 is a 96 kHz 24-bit sigma-delta DAC, used in both th2 ULN2 and 2882 The AKM 5394 is a Multi-Bit 192kHz 24-bit sigma-delta ADC…
———-[Mobile IO Analog Stage]———– Both the ULN2 and 2882 use the Excalibur low-noise high-speed JFET-input op-amps from Texas Instruments, and the ULN-2 adds Burr-Brown OPA 2228 op- amps for high precision and low noise in high-gain situations.
————–[MIO Mic Gain]————– the ULN8 has +90 dB of gain on recallable headamps the ULN2 has +72 dB of gain on non-recallable headamps the 2882 has + 42.5 dB of gain on recallable headamps
————–[MIO Mic Sensitivity]————– Sensitivity c.a. 20mV/Pa recommended for use with MIO If x = sensitivity in dBV e.g. -66dBV/microbar(.1Pa) then sensitivity in mV is 10^(x/20) * 1000 5mV/Pa, or .5mV/microbar AKG C3000B mV/PA: 25 Baby Bottle PA: 35.5 AKG C480 mV/PA: 40 DPA 4053 mV/PA: 30 Audio-Technica AT4033 PA: 19.9 DPA4060 mV/PA: 20 Audio-Technica AT4050…
————–[Power Suppy and Consumption]————– The minimum pre-regulation voltage is 9V. The Maximum preregulation voltage is 33V. At 12 Volts the current demand is: ULN-8 : 3-3.5A 2882 High Power Mode 1.5A 2882 Low Power Mode 1A ULN-2 : 0.75A A custom jump boot device can be be built with a pair of 9V batteries. It…
————–[ULN-8 DB25 Breakout Cables]————– The ULN-8 uses US inch sized DB25 of # 4-40 sized thumb screws . This is the same standard that Digidesign,Tascam, and Panasonic use. Cable Number Hot DB25 pin Cold DB25 pin Ground DB25 pin 1 24 12 25 2 10 23 11 3 21 9 22 4 7 20 8…
————–[ULN-8 Input Specs]————– Are located at MH Labs
————–[ULN8 Input Diagram]————–
————–[ULN8 Front Panel Controls]————– The official ULN-8 front panel guide is located at MH Labs. The translated version found on this site is archived. — Meters on the Knob — When the Front Panel is in Input Trim mode: Input Meter mode: to toggle between meters on the knob mode and dual vernier mode, press…
————–[2882 Headphone Outs]————– A couple of things to be aware of with respect to the headphone output: A) the outputs were designed to work best with high-sensitivity type headphones (like the Sony studio monitor headphones). They will work fine with low-sensitivity types (600-ohm broadcast cans), but they will not be able to get very loud…
————–[Metric Halo SHARC 80 bit]————– Mobile I/O uses the Analog Devices SHARC 21065 DSP. This is a 40 bit floating point processor which can also do 32 bit fixed point with 80 bit accumulation. For large MAC (multiply accumulate) loops, like summing in a large mixer, wide fixed point processing can provide better results, but…
————–[ULN2 DI]————– the TRS on the Combo Jack is 200K, which is pretty Hi-Z and would be a good DI.