We measure audio equipment for free!!!

[krabapple]

Gee, I didn't think that engineers still had to be told not to exceed 0db on the record level meter. I learned that back around 1960 when I got my first tape recorder from Allied Radio.

Unless they use a meter that flags intersample overs, they aren't seeing them. They think they aren't exceeding 0dBFS.

 

[Sal1950]

Unless they use a meter that flags intersample overs, they aren't seeing them. They think they aren't exceeding 0dBFS.

Then the manufacturers have to use different meters so the engineers have a proper tool to work with...
I do wonder how big an audible issue this is or are we once again chasing a jitter ghost?

OTOH since I'm a multich enthusiast and probably 70+% of the music I've purchased in the last decade has been 5.1ch or better I'm living in green acres.

"With more than 7,000 tracks analyzed, notice that there were ZERO tracks with true peaks above 0dB and 99% of tracks have true peaks below -0.44dB!

This is what healthy digital mastering looks like without strong dynamic range compression! As discussed, multichannel audio sounds and measures with higher dynamic range. Let's hope that the mastering studios continue to respect limits on output levels as defined by Dolby and Apple's target of integrated loudness value not exceeding -18 LKFS. To be honest, I would rather listen to a lossy high bitrate EAC3-JOC Atmos than the typical DR8 stereo lossless version stripped of dynamics and nuances."

 

[krabapple]

Then the manufacturers have to use different meters so the engineers have a proper tool to work with...

I'm not sure what manufacturers you mean. Certainly 'true peak' meters exist, it's just up to recording production engineers to use them.

 

[Sal1950]

I'm not sure what manufacturers you mean. Certainly 'true peak' meters exist, it's just up to recording production engineers to use them.

The ones that put the meters in the recording gear.

 

[krabapple]

The ones that put the meters in the recording gear.

Pretty much every DAW that pros use has a true peak metering plugin. This isn't a new thing.

It's an issue that can be addressed either at the production end, or at the consumer DAC end.

 

[Sal1950]

Unless they use a meter that flags intersample overs, they aren't seeing them. They think they aren't exceeding 0dBFS.

Pretty much every DAW that pros use has a true peak metering plugin.

Now I'm confused by the two statements..
In the first you allude they don't have a meter to see the overdriven master.
In the second you say they already have the meter in the DAW.
Which is it?

 

[krabapple]

? Having true peak metering available for a DAW doesn't guarantee the engineer is using it.

They're using traditional peak metering instead, which is absolutely there on all DAWs.

 

[Sal1950]

Having true peak metering available for a DAW doesn't guarantee the engineer is using it.

Pretty much every DAW that pros use has a true peak metering plugin.

So the claim is they have the meter but ignore or don't use it?

 

[krabapple]

Yes. Does this amaze you?

In Audacity or Audition I have 7+ options for FFT analysis of frequency, but I only really ever use one.
Ditto the multiple options for nearly every tool the softwares offer.

There are various kinds of metering available in software. Engineers have used traditional metering since forever, and it doesn't show overs. So everything looked fine. And really, sounded fine too. You can't always hear overs.

• Engineers have to be aware of overs first. (They were first written about in the technical literature circa 1999/2000(?), but were not immediately appreciated.)
• And then they have to be convinced it matters. (Enough to possibly slow down their workflow -- traditional metering uses 1/100th of the CPU that true peak metering uses)
• And then start using the available tools.

That's why the videos and sites going back a decade or more exist, to make that happen.

The problem is not 'the manufacturers' of DAWs, not in 2025.

 

[Sal1950]

Yes. Does this amaze you?

No but your posts made it sound like either the tools didn't exist or the engineers aren't aware of proper modern level control. We all know the reality of the loudness war, but are the driving reasons? This practice isn't really the "fault" of the engineers or them being ignorant of the available tools, it's more an issue with the general industry.
The recording engineers I know and respect mostly don't involve themselves with this practice as Archi posted above about what goes on in the multich world. But when we end up with artists-industry that WANT their music to sound that way, what can they do? Think Taylor Swift doesn't want her albums to be the loudest sounding on the stream?. Mark Waldrep of AIX records has posted how in disgust he's had his masters returned 2,3 and 4 times with instructions to "Make It Louder". You either make your stuff sound the way they want or you go out of business as Mark has recently done with AIX. Guys like Steven Wilson, Bob Clearmountain, Alan Parsons, Chuck Ainlay, Bob Clearmountain, Giles Martin, many more have the name, muscle, and financials not to dance to the tune of demands they'd rather not.
Unfortunately, except for the end product made for a small group of enthusiasts, I can only see things getting worse, think all the "music" being created by AI is going to give a crap about intersample overs?

 

[Power Pop 23]

Consider creating a separate thread for the topics covered in posts #480 to #490 of this thread.

 

[absolutehifi]

Yes, you read the title right. If you have audio gear that you like to see objectively measured with professional equipment, we (I) may be interested in doing that for you and our readers.

There is so little objective data on equipment today. Even if you are not an "objectivists" it pays to contribute to gathering some data to weed out poorly engineering products of which, there are many. Electronic design and building of audio equipment has become much easier today, allowing so many unqualified people to get in the business and building potentially unsafe and non-performant equipment. It is important for data to show such poor practices. At the same time, there are also superbly designed equipment and they deserve standing out from the crowd and dust of all the other gear.

If you are interested in participating, all you have to do is "start a conversation with me" by clicking on my name/avatar and we can work out the logistics. Typical lead time from when equipment arrives is 4 to 5 weeks. Exceptions can be made which we can address in the conversation.

Note that there is some risk of gear getting lost, damaged, etc. The rate of this thankfully has been as low as 0.1%. Still, if you are concerned, you can use insurance to cover shipping losses (and I can do the same in reverse).

Also note that accommodating shipments from outside the US can be very difficult. Small items can be managed. Larger items, especially if they are low cost, don't make sense to send back and forth.

So let's join hands and work together to create a large and useful library of objective, reliable and repeatable data for users to make good decisions in purchasing audio equipment, and to guide manufacturers to build better products.

Speaking of manufacturers, I am more than happy to see them participate too and indeed a number have. I make no assurance whatsoever of happy outcome should you loan me the equipment. What I can promise is supporting you in troubleshooting problems that are revealed in my testing and review.

Thanks in advance for those of you who participate.

Hi Amir, are you still interested in testing people's audio gear for free? I am a pianist/audiophile/electrical engineer and I have a modified Rotel RB-1070, whose circuit is still in use today in Rotel RB-1552 MKII. I use the amp to drive a pair of Dynaudio C4 speakers. I like the circuitry of the amp -- it is simple and fully symmetric (dual differential plus Darlington triples), but I wasn't not quite satisfied with the sound. After modification, the sound improved drastically and I am quite happy with the results. I am curious to see how it measures, and whether the measurement corroborates with my intention for the modification. If you could kindly measure the amp, I'd be happy to share with your readers what I did and the theory behind the modification. In particular, I am interested in seeing the THD vs. power output curves under 8 ohm and 4 ohm loads. Please let me know if you are interested. Thanks!

 

[Sal1950]

Hi Amir, are you still interested in testing people's audio gear for free? I am a pianist/audiophile/electrical engineer and I have a modified Rotel RB-1070, whose circuit is still in use today in Rotel RB-1552 MKII. I use the amp to drive a pair of Dynaudio C4 speakers. I like the circuitry of the amp -- it is simple and fully symmetric (dual differential plus Darlington triples), but I wasn't not quite satisfied with the sound. After modification, the sound improved drastically and I am quite happy with the results. I am curious to see how it measures, and whether the measurement corroborates with my intention for the modification. If you could kindly measure the amp, I'd be happy to share with your readers what I did and the theory behind the modification. In particular, I am interested in seeing the THD vs. power output curves under 8 ohm and 4 ohm loads. Please let me know if you are interested. Thanks!

As a general rule, testing needs to have value for the membership. Otherwise, it will just be private testing. So equipment that is not in production doesn't fit the charter of what I test. You are always welcome to commission a private test for which I charge less than industry rates but it is not free or very cheap.

 

[absolutehifi]

Thanks for your reply! I would say investigating my modified amp may be of greater interest to many of your members than measuring a vintage CD player or amp, which by itself is very interesting (as least to me) . Of course it depends on what the mod comprises. For my Rotel RB1070, I increased the bias current of the push-pull stage to match the impedance of my Dynaudio speakers, which is 4 Ohm nominal, and as low as 2.8 Ohms at some frequencies. The idea is that a class AB amp designed for 8 ohm load will not be optimum for 4 ohm speakers and vice versa in terms of distortion. Obviously measuring this mod would elucidate on this issue, and I believe it would be of tremendous interest to many here, as the issue is not limited to Rotel RB-1070, but relevant to all class AB amplifiers. Anyways, how much would you charge for a private test, just for THD vs. output power under 8 Ohm and 4 Ohm load? Thanks again!

 

[Sal1950]

Anyways, how much would you charge for a private test, just for THD vs. output power under 8 Ohm and 4 Ohm load? Thanks again!

Contact Amir directly via a PM,

https://www.audiosciencereview.com/forum/index.php?direct-messages/add&to=amirm

 

[napfkuchen]

Thanks for your reply! I would say investigating my modified amp may be of greater interest to many of your members than measuring a vintage CD player or amp, which by itself is very interesting (as least to me) .

You might want to contact @NTTY if you are interested in sending in your old cd player for review. Most of the older players are still good enough by todays standards but the built quality is on another level. Also the simple/straightforward design is a plus (personal Taste) and there are only a few - for the most part exotic and expensive - devices in production.