DM-3200 headroom issue

[earlevel]

Using an external mic preamp, at some point, I noticed that I could no longer drive the channel input anywhere near full 0 dB without clipping. I did some debugging:

I'm using an old Fostex TT-15 test tone generator (sine out, choice of five frequencies and three levels, into the line input. I'm primarily checking with 0dB output and either 400 Hz or 1 kHz signal. I verified that the sine sounds pure at -16 dB on the meter, is clipping at -12. Via the IF/FWDM mkII card, I verify that Digital Performer shows those levels coming from the mixer, and the sine is pure at -16, clipped at -12. Further, there is significant overshoot, indicating that the clipping is occurring before the ADC, and the ADC has headroom to spare.

I tested most of the other line inputs, they all had this problem, but to different degrees (clean/clip at -12/-8, -20/-16, etc.). I've created newly initialized projects, verified digital trim is 0 dB, etc.

Am I missing something?

PS—Connecting the tone generator at 0 dB to an assignable return (which has no analog gain adjustments), and routing to a channel, yields -20 dB on the meter (pre-fader level). So, basically, this is behaving as though there is a 20 dB pad before the ADC on each input.

 

[earlevel]

Let me modify my "PS" comment about -20 on each input. I have full input on the first three channels (0 dB from the tone generator pegs the meters with Trim about 1 o'clock or greater). Overall, the input channels vary—channel 9 is full scale, but 10 is -12, etc. The assignable returns are all exactly -20 dB.

On channel 4, seeing something weird...it's not full scale like 1-3, but it also lights the lowest led on the meter bridge for channel 5—extra strange.

I cleared the SRAM, wiped the settings, that's what I'm seeing.

 

[earlevel]

Time to retire it. Ordered a Ferrofish Pulse 16 MX and MOTU M64. Covers my needs and I can always run digital in and out of the DM-3200 via ADAT ports if I want to.

 

[Peter Batah]

Had you considered The Behringer X32 as a DM replacement by any chance?

 

[earlevel]

The Behringer mixers are very interesting, and I'll definitely consider them if I decide I need a traditional mixer. I've always had one, even though I've underutilized them for the past 20 years due to mixing in the box. A mixer is just a convenient way to bring my inputs (mostly keyboards) in and have a quick way to adjust monitoring levels of each, and to act as a digital interface for the DAW. I've never adjusted EQ or compression on a channel, mainly just reverb on the mic channel that I can bring up or pull down when auditioning or tracking vocals. I use the routing capabilities extensively, but I'll have that in the boxes I'm buying, and could even access everything from an iPad.

So, I can probably get by fine without a mixer. If I weren't experiencing the level issues, I'd certainly use the DM-3200 for additional inputs and monitoring. I could still use it purely digitally, and maybe that will be handy. The 16 ADAT channels on Pulse 16 MX to the DM (I have an old MOTU 2408 MkII that can format convert the remaining 8 to TDIF, at the cost/work of a cable).

The DM-3200 served me well. I had a different digital board that was stolen in 2005, insurance let me buy an equivalent, since the other was out of production, and the DM-3200 plus meter bridge was a step up.

I'm interested to find if I can hear the difference with the more modern converters. I've seen no tests on the Ferrofish, but people speak highly of them even in comparison with elite converters. Will it make a difference?...

 

[Peter Batah]

You will keep us posted of course !!!

 

[-mjk-]

The Behringer mixers are very interesting, and I'll definitely consider them if I decide I need a traditional mixer. I've always had one, even though I've underutilized them for the past 20 years due to mixing in the box. A mixer is just a convenient way to bring my inputs (mostly keyboards) in and have a quick way to adjust monitoring levels of each, and to act as a digital interface for the DAW. I've never adjusted EQ or compression on a channel, mainly just reverb on the mic channel that I can bring up or pull down when auditioning or tracking vocals. I use the routing capabilities extensively, but I'll have that in the boxes I'm buying, and could even access everything from an iPad.

But, after I got one 3 years ago, this happened. In a nutshell, not a DAW controller but console automation using the audio engines in the X32. This is a modern re-creation of the legacy console automation systems but with the controllability and instant recall of over 10,000 parameters of the digital console.

 

[-mjk-]

Had you considered The Behringer X32 as a DM replacement by any chance?

I like the M32 better, but they are hard to find here. Truth be told, I had intended to get a DM4800 because of the native automation but it had already been discontinued.

 

[earlevel]

So far, the M64 + Pulse MX combination is a good fit for me. I have external mic pres, usually use only a single vocal mic, mix ITB. Having everything in a rack next to my keyboard stack has simplified cable routing. The only downside is the tiny meters, compared to my DM-3200 with meter bridge, but I only use them for setting initial gain.

Just under $2k got me 16 x 16 balanced i/o, and have untouched for expansion: 64 channels of MADI on coax in addition to the remaining 48 unused on optical, AVB port, and 32 x 32 ADAT i/o. Can mix wireless on iPad.

Routing on the Pulse is in banks of 8, and doesn't do mixing; its headphones output can only be fed by mono or stereo pairs of analog, ADAT, or MADI. Enough flexibility to use it as a standalone converter. Of course, the M64 is what supplies routing from anything to anything (including splitting), and multiple mixes. In my case, I'm routing all input to "the computer" (my DAW). I only do stereo mixes, so I'm routine that stereo pair "from computer" (DAW) to a stereo mixer in the M64, summing with all the analog inputs for monitoring the instruments live at "zero" latency. Since the virtual mixer channels can be stereo, the channel count is a lot smaller with my stereo instruments than required with the DM-3200. Of course, the M64 also has a headphones output, and that mix can be whatever you want.

The virtual mixer is built from just the components specified by the user, and routing matrix from user-specified limits, which makes it a lot easier to deal with. But there is a bit of a learning curve to understanding the system. For me, the last hurdle was realizing that the "to mixer" (sounds like inputs, right?) choices lived in the "Outputs" section. That, and if there doesn't seems to be a way to get an input to the mixer, it might be because you have to go to the routining page and make sure you have that device, or the appropriate number of channels, enabled.