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The opposite of an attenuator?

I'm surprised it costs £400 for a decent (i.e. transparent) DAC with balanced outputs these days. I have a ten-year-old DACMagic Azur with balanced outputs. The equivalent ought to cost peanuts today...
 
See the spec
https://www.meridian-audio.info/show.php?compid=183

Sensitivity: 775mV (adjustable to 78mV) (ie Line Level and down to 10% Line)

There should not be a level mismatch

Had a look at instructions and no mention of variable sensitivity.... or anything about sensitivity in fact.. but the spec at the end says it's "0dBm 775mV, over 22K, balanced or unbalanced" so there should indeed not be an issue.
 
I'm surprised it costs £400 for a decent (i.e. transparent) DAC with balanced outputs these days. I have a ten-year-old DACMagic Azur with balanced outputs. The equivalent ought to cost peanuts today...
topping D10 balanced for £100 or so. Various others from Soncoz etc. I imagine a decent pre-amp would not be much less.
But I don't understand what the problem is. Does the OP really listen to the active speakers at full blast? If not what's the problem?
 
I suspect I may be back to getting a balanced DAC and custom cable.
Balanced DACs typically output twice the voltage of single-ended DACs, so 4Vrms instead of 2Vrms. This gives +6dB more gain. Are you sure +6dB more SPL at your listening seat will be enough? There are some balanced DACs that output up to 10Vrms which would give +14dB more SPL but these are few and far between.
 
topping D10 balanced for £100 or so. Various others from Soncoz etc. I imagine a decent pre-amp would not be much less.
But I don't understand what the problem is. Does the OP really listen to the active speakers at full blast? If not what's the problem?

Presumably he’s running out of room on the volume dial and wants a bit more headroom?
 
Presumably he’s running out of room on the volume dial and wants a bit more headroom?
It's a novelty to see the problem this way round. The usual inquiry is about trying to attenuate the dac output in order to avoid having to turn the vc right down.
 
Just as a sanity check: what is the source, and does it have its own (possibly software-controlled) volume control? E.g. is it a computer and have you checked that the software mixer is at max volume?

Sad to say, that happened to me once...even wrote a panicked thread here trying to figure out why my volume was suddenly way lower than expected.
 
Just as a sanity check: what is the source, and does it have its own (possibly software-controlled) volume control? E.g. is it a computer and have you checked that the software mixer is at max volume?

Sad to say, that happened to me once...even wrote a panicked thread here trying to figure out why my volume was suddenly way lower than expected.

Chief problem source is the TV, which has a ridiculously quiet PCM output. I may have a dig around and see if I can fix it when the kids aren't about.
 
Chief problem source is the TV, which has a ridiculously quiet PCM output. I may have a dig around and see if I can fix it when the kids aren't about.

TV setup can be a bit of a nightmare for this sort of stuff. But if you can't improve things at the TV end, I'd definitely urge you to investigate adjusting the input sensitivity of the Meridians, since the spec sheet says there's a way to do that. (But you might need a service manual to find out how to do that - or help from Meridian.) Adding a preamp would be a sledgehammer option when there's a way to add gain (effectively) built into the speakers.
 
TV setup can be a bit of a nightmare for this sort of stuff. But if you can't improve things at the TV end, I'd definitely urge you to investigate adjusting the input sensitivity of the Meridians, since the spec sheet says there's a way to do that. (But you might need a service manual to find out how to do that - or help from Meridian.) Adding a preamp would be a sledgehammer option when there's a way to add gain (effectively) built into the speakers.

They are not adjustable for sensitivity.
 
Now I'm confused. Why does the spec sheet say they are then? (see https://www.meridian-audio.info/public/m30_spec[383].pdf)

(Also mentioned in posts 22, 24 and 25 above.)

Because it appears to be simply wrong. Read the instruction manual and see if you can find any mention of it being adjustable. Post 24 was mine in which I pointed out that the instruction manual gives only 775mV as sensitivity.

It may be possible to modify them to be more sensitive by changing a couple of resistors but without schematics or being able to examine them I couldn't say.
 
Because it appears to be simply wrong. Read the instruction manual and see if you can find any mention of it being adjustable. Post 24 was mine in which I pointed out that the instruction manual gives only 775mV as sensitivity.

It may be possible to modify them to be more sensitive by changing a couple of resistors but without schematics or being able to examine them I couldn't say.

The spec sheet says the sensitivity is "internally adjustable". Since manufacturers generally don't encourage users to poke around inside their gear, it doesn't surprise me that the user manual makes no mention of the adjustment. But perhaps Meridian (or their service agents) can do it, or advise about it. Worth exploring surely.
 
Chief problem source is the TV, which has a ridiculously quiet PCM output. I may have a dig around and see if I can fix it when the kids aren't about.
From what I read, the TV PCM output level seems to be completely mad.

For the M30, 775 mV sensitivity for 106 dB SPL (what I assume from the spec. and seems OK to me) is equivalent to 2 V (full DAC output) for a deafening 114 dB SPL (nominal). If you can't get enough volume when the DAC volume control is fully up it looks like the TV sound average level may be a massive 48 dB down from full scale, or more. That's equivalent to a digital shift-down of a full 8 bits. That looks like a lot for an amplifier to fix, even partially.

I assume connecting another digital source to the DAC gives good volume levels when the DAC volume control is turned down - although I note your "Chief problem source" which makes this less clear. But if so, it seems the fundamental problem is with the TV or what the DAC sees from the TV over the digital audio interface (TOSLINK I assume).

What is the TV doing? Does the TV digital audio output level follow the TV's internal volume control so you see the combined effect of both controls?

Is the DAC somehow seeing only 8 bits of digital audio from the TV and interpreting these as the bottom 8 bits of 16-bit digital audio when it should see them as the top 8 bits? Is the TV putting out 16 pit PCM but the DAC is interpreting that as 24 bit PCM with zeros at the top? Is there a TV menu setting for the digital output that you can share that may shed some light? Is there any DAC input setting that may matter?

These thoughts all seem mad to me but something needs to explain the magnitude of what is being heard. Or have I got the situation wrong?
 


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