Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems Sony 550 and LFE levels via analogue

I've read the thread from last year's forum which discusses the 10dB cut on the discrete preset so that isn't the issue.

I've connected 5.1 outputs to MA1 on a G68 and I'm still having to set all other speakers to -10dB on the Sony 550 to get the expected balance from the sub using its internal test tones or tones from a test disc. Sony and G68 both at latest firmware.

Tim

Hi Tim,

That's interesting, I have the same setup and it sounds fine to my ears using the Cinema preset. I must confess to not using the internal S550 test tones though.


Cheers
Mike

I would try checking with a test disk, not sure if sspears new BD test disk has audio tests, if it does I'm sure it's done right.

Also as was told to me using the DVE test disk it was not in an error that the bass was -10db as that is how it should be measured so it may depend on what it's supposed to read.

How does it sound to your ear?

Sounds fine to me. I think I read that the Sony S550 should have all the speaker distances set the same and all levels to zero. I'm sure it was in this forum but I could be mistaken.

Cheers
Mike

It doesn't sound at all bass heavy watching "Hancock", but I don't have a copy on DVD to compare. We've got about 10 copies of "Zulu" on DVD so when I get the BD version I'll compare DVD, analogue BD and digital BD.

It's all academic really as I'm picking up a HD621 tomorrow, I was going to borrow one on dem but I knew if I did I'd end up buying it, so I've missed out the middle man.

Tim

Yes, it in the wiki among other places. But I'm not sure that's related to your issue.

I assume you understand the difference between cinema and discrete (default LFE offsets).

George,

I don't have any issues, it's Tim who has them

Cheers
Mike

I do understand that Discrete has LFE set to -10dB and Cinema to 0 at default, but the 550's test tones and and DVD I try (DVD-E PAL and NTSC, and Avia) show that the bass channel is 10dB low on the meter with the levels set at 0. I searched before posting and it pulled up 4 answers from 2008 all of which referred to the 10dB difference in presets.

I've only watched one film so far which didn't sound bass heavy. It will be interesting to see what readings the same discs produce via the HD621. They produce expected results through the SP-DIF output.

Edit: The Ovation disc certainly does I didn't try DVD-Essentials through SP-DIF.

Tim.

I've managed to set up a Google search that pulls up lots of reviews, articles and forum posts regarding this exact same issue. It probably isn't news, but unless I'm very much mistaken the G68 isn't handling it exactly as it should. The LFE analogue output should be 10dB low by spec., I haven't been able to exactly fathom why yet, but I've read it in enough places to believe it.

There should be a way of raising the LFE by 10dB elsewhere in the chain so that disc test levels produce equal dB across the spectrum. I can't believe the mastering levels of BD are going to be manifestly different from DVD as there is no way of compensating for that in a player that by design can cope with playing both disc standards. Other manufacturers (other than Meridian) have a method of compensating for this issue so that when playing via 5 or 7.1 analogue outputs 10dB boost is added to the .1 channel.

In my case it certainly isn't selecting Discrete instead of Cinema - I cottened on to that one straight away. I honestly think that the Meridian's analogue input isn't coping with 5.1 analogue audio from BD players as it should be, or I'm missing something very obvious. SPDIF comes out 10dB higher, and I'm willing to bet the HD621 will too from speaking to HD621 owners privately today.

I'd love to be proved wrong.

Tim

My memory may be failing but I think I used the Avia BD disc and it measured 10db down and folks here said that is correct.

It is correct the bass output should be 10dB lower, but something at the other end needs to compensate for it, which in this case doesn't appear to be happening.

If you play the same disc's test tones through the HD621 or SPDIF you don't get the 10dB drop - (provided you've calibrated your Meridian properly).

Say when you play the tones you get 75dB on your meter. If you play the disc through a digital input you get 75dB through your sub at the listening position on the bass channel. That is no different from a mixing engineer setting the bass levels to 75dB when mixing a soundtrack. From the searching I did this evening other manufacturers boost the bass channel at the input and it appears that Meridian don't.

I might be missing something and making a complete fool of myself, it just doesn't seem right to me that the same test tones played through three different transport methods don't end up with the same result at the speakers.

If we were just talking about the player's built in tones I'd understand exactly where you are coming from but we aren't we're talking about a disc mastered so that on a properly calibrated system pink noise sounds the same through each channel. That's what the Avia disk is set to measure. Don't forget BD players are by definition backwards compatible - would the output on the bass channel on the DVD of helicopters strafing the village in Apocalypse Now sound 10dB lower because you were connected through 7.1 analogue? Play the same sequence though analogue and then through SP-DIF, and you'll hear a difference in levels. Someone won't have sneaked into your house and remastered the back catalogue of DVDs you bought in the last ten years.

At least I hope you will otherwise my brain has turned to jelly(o)

Has it only been 10 years? What are we going to be watching in 2019?

Tim

The post in this thread by Mark_H I think explains the confusion.

https://www.meridianunplugged.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=79018#Post79018

The whole reason for this LFE offset is for increasing SPL Level of the sub without clipping (probably with in a 16bit word).

The ONLY thing that SHOULD really be reboosting the the LFE by 10db is the ANALOG amp !!

I think internally Meridian has more range in the digital domain and plays some games to do in the digital domain. But technically it's the sub that should be boosted 10db. I assume test tone for a pure LFE sub is -10db so that it's effectively 10db high.

What Meridian does when you have no sub who knows.

It sounds wrong to boost it at the input and defeats the whole purpose.