Topping DM7 8-Channel DAC Review

[Hmast]

It's 5V/14dBV/16.2dBu.
You decide whether that's "pro or consumer".

I'm not an expert at all with those figures. If I take a look here: https://en.wikipedia.org/wiki/Line_level

It looks more on the pro side, but 5V and 14dBV sounds huge.

 

[staticV3]

@Hmast "Consumer level" vs "Pro level" is really from a bygone era, so it makes little sense to classify current equipment as one of the other.

 

[Hmast]

Well, I currently own one source of each of these "classes" and the difference is HUGE (SSL2 vs GoXLR). So... I was simply wondering how loud it will get.

I think it's going to be my loudest source by far.

 

[Trell]

I'm not an expert at all with those figures. If I take a look here: https://en.wikipedia.org/wiki/Line_level

It looks more on the pro side, but 5V and 14dBV sounds huge.

Note that balanced output usually have double the voltage (6 dB) of RCA, so 4V or more for balanced is common. There are a few examples of balanced output being less that 4V , as I recall.

 

[staticV3]

I think it's going to be my loudest source by far.

Louder yes, but not by far. If you set the DM7 to 5V output (default is 4V), then it'll be about 30% louder than your SSL2.

 

[mgbpuff]

Line levels and their approximate nominal voltage levels

Use	Nominal level	Nominal level, VRMS	Peak amplitude, VPK	Peak-to-peak amplitude, VPP
Professional audio	+4 dBu​	1.228​	1.736​	3.472​
Consumer audio	−10 dBV​	0.316​	0.447​	0.894​

 

[mgbpuff]

I have JBL 305p MkII professional powered speakers. I set the input sensitivity of them to -10dbv and the volume knob at mid. This gives good results. (DM7 is at default 4v, connector is TRS to TRS)

 

[staticV3]

Line levels and their approximate nominal voltage levels

Use	Nominal level	Nominal level, VRMS	Peak amplitude, VPK	Peak-to-peak amplitude, VPP
Professional audio	+4 dBu​	1.228​	1.736​	3.472​
Consumer audio	−10 dBV​	0.316​	0.447​	0.894​

No consumer audio equipment sold in the last ~5 years uses 0.316V level.
An RME ADI-2 Pro will output +24dBu.

Those numbers you're quoting come from a time when CD was still the primary medium for digital audio.
They're just not applicable anymore nowadays.

 

[Trell]

No consumer audio equipment sold in the last ~5 years uses 0.316V level.
An RME ADI-2 Pro will output +24dBu.

Those numbers you're quoting come from a time when CD was still the primary medium for digital audio.
They're just not applicable anymore nowadays.

But there is an opportunity for confusion with respect to max output voltage vs voltage plus headroom, at least for me. Here is from the RME Fireface UCX II released summer 2021:

 

[mgbpuff]

No consumer audio equipment sold in the last ~5 years uses 0.316V level.
An RME ADI-2 Pro will output +24dBu.

Those numbers you're quoting come from a time when CD was still the primary medium for digital audio.
They're just not applicable anymore nowadays.

That may be true, but standards are standards, and .316v is the consumer 0db standard voltage and 1.228v is the pro standard. If you have greater input / output capabilities, then just adjust to your liking given your particular equipment.

 

[staticV3]

That may be true, but standards are standards

They are standards only as long as the industry adheres to them.

and .316v is the consumer 0db standard voltage

*used to be.
Nowadays, the consumer 0dBFS standard Line voltage is more like 2.0V

 

[mgbpuff]

They are standards only as long as the industry adheres to them.

*used to be.
Nowadays, the consumer 0dBFS standard Line voltage is more like 2.0V

You don't seem to understand the word "standard", nor do you seem to want proper overhead for music, which the "old" standard provides.

 

[KSTR]

That may be true, but standards are standards, and .316v is the consumer 0db standard voltage and 1.228v is the pro standard.

But those are output voltages for the nominal ("0VU") levels used around mixing desks and tape machines, back from the old analog days. 0dBFS of digital devices is higher to afford some headroom for peaks.

With 0dBFS = 2Vrms (+6dBV) for consumer devices we get an adequate 16dB of peak headroom (for pre-loudness-war recordings, that is).
and for pro gear, 0dBFS may range up to +24dBu, giving 20dB of headroom versus nominal +4dB. Some units have options to use less headroom (see the RME example).

4Vrms of the DM7 is +14.3dBu, so we would have a nominal 10dB of peak headroom when used in a SPL-calibrated +4dBu pro environment.

Connected equipment should be tolerant to high levels of about 6Vrms (+18dBu) before any volume control to avoid clipping, that's the thing to know with the DM7. In doubt you can always dim down the balanced signal with a balanced resistor L-pad right in the down-stream connector of the cable.

 

[Hmast]

Connected equipment should be tolerant to high levels of about 6Vrms (+18dBu) before any volume control to avoid clipping, that's the thing to know with the DM7. In doubt you can always dim down the balanced signal with a balanced resistor L-pad right in the down-stream connector of the cable.

How can we know?
I plan to use this DAC with 100% volume in Windows straight to the active speakers. Volume is managed directly on the speakers.

Speakers' manual: https://assets.ctfassets.net/4zjnzn...3286ab27d0a0/8351B_operating_manual_rev_b.pdf

Maximum analog input signal: +25.0 dBu
Analog input sensitivity (100 dB SPL at 1 m): -6 dBu
Analog input sensitivity control: Adjustable from +36 to -6 dBu

 

[KSTR]

How can we know?
I plan to use this DAC with 100% volume in Windows straight to the active speakers. Volume is managed directly on the speakers.

Speakers' manual: https://assets.ctfassets.net/4zjnzn...3286ab27d0a0/8351B_operating_manual_rev_b.pdf

I think you are safe. With the sensitivity control set to high values the Gen's will have no problem with the DM7 output levels.

 

[himey]

nor do you seem to want proper overhead for music

If this device had 10 or 12 channels, it would make for a proper overhead for music. But as it stands, it is limited to only 2 height channels in a normal (Atmos) configuration.


/s

 

[Trell]

If this device had 10 or 12 channels, it would make for a proper overhead for music. But as it stands, it is limited to only 2 height channels in a normal (Atmos) configuration.


/s

I still only have a 5.1 setup and with no plans to add height speakers.

 

[mgbpuff]

If this device had 10 or 12 channels, it would make for a proper overhead for music. But as it stands, it is limited to only 2 height channels in a normal (Atmos) configuration.


/s

I was talking about overhead in terms of dynamic range or headroom.

 

[himey]

I was talking about overhead in terms of dynamic range or headroom.

I had no idea...
Again, /s

 

[mgbpuff]

I had no idea...
Again, /s

O.K. I get it! You're being sarcastic (/s). Good for you! /s