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RME User Forum → ADI-2 & 2/4 Pro series, ADI-2 DAC series → ADI-2 FS vs integrated amp DAC
Gotta run out for an Appointment Stu I'll take a look shortly.
Curt
interesting also: https://www.youtube.com/watch?v=1d9WmjTJniI
Hi Stu!
Nice Video. We could debate this, that, and the "other thing" all day, but the REAL Take-Away is that Speaker, and Seating Location truly IS a big deal! This may come as a surprise to some, but you truly cannot fix Set Up/Room issues with Magic Cables. 
With that said, and so that this topic does not obscure your original thread. perhaps you might consider starting a new thread! This Topic is of Great Interest to many, and as long as we're exploring the means by which can we get more from our RMEs, Admin would likely not object.
Whatchya Think?
Curt
Agreed Curt, from mid of post #44 and all thereafter content can be moved into a new thread. I've edited the post so that you can see where the old topic stopped and the new topic started.
OK! Cool!
On your Microphone. It seems you could use the Superlux w/o any major issues. It's worth a try!
We are not calibrating a 3D Sonogram Transducer, so absolute accuracy is not truly required. Some means of observing the characteristics of our Room, and deriving from that a nice overview of goings on is acceptable IMO. My Son once used a "My Favorite Pony" USB Mic borrowed from my Grandaughter. Laugh! . But he was able to see a respectable overview (+/-) of what was happening in his room.
Give the Superlux a whirl. You've nothing to lose.
Curt
I succeeded. After few crashes I got out a nice (tab=SPL) graph with some straigh spikes but also some wider ups or downs.
Post a Pic. You'll need to use a image hosting program. I've had good luck with Imgbb, but there's others to choose from.
Stu, I'm not seeing your Room Dims. Im sure you posted them, but no joy looking for them now.
Re-Post maybe?
Warming up my Crystal Ball.
Thx!
Ok Stu. I'm in the Colonies, and we Cling to our Imperial Measures! It took me a minute to convert from Metric.
Assuming I've read your Room Dims shorthand correctly, my Crystal Ball sees a 35hz Mode in the 5M dimension. (We see that!) The 6.7M dimension does not appear. As it would be located at 26hz, it's seems likely your Speakers simply don't excite that mode. That big peak at 63hz? We see that Beauty too. That's your Vertical Dimension Guv'nr!
Now what??
Methinks we have work to do.
Let's start by putting some smoothing on the Graph. 1/6Oct is fine. Find this function by clicking the "Gear" Icon in the upper right of the screen. A bit of Smoothing on the data simply makes things a bit more digestible. Easier to read.
Curt
horrible spike at 66.
and @1/6 https://www.imgurupload.com/uploads/202 … 3e519a.png
Hmm...a bit easier to read wouldn't you agree? We clearly see the Ht.Mode. The depression at 45hz is puzzling, but we can figure that out. Do you happen to be approx 1.9M from a Room Boundary at the Listening Position? That'll do a fine job of taking a bite out of 45hz.
The Ht. Mode at 65ish hz could be pulled down with a "mid" Q EQ Cut of about 5db or so. The other Jibberish higher in freq is a bit like Comb-Filtering. Lots of un-restrained boundaries that "Sing" to the Mic in a myriad of Phase Relationships which results in the "Choppiness"
Stu, in the Grand Scheme of things, I think we're in a manageable situation.
If we knew more about your install within the Room, and maybe even a Pic just might give us the Clue we need for improvement!
This seems doable!!
Curt
Side Note!
Folks, when we think about Room Modes, etc...I find it helpful to think in terms of Wavelengths!
A handy tool I learned years ago was as follows.
*Speed of Sound/2=our "Constant"
Using that Constant, we can divide that number by the Room dimension to calculate quite accurately where the primary Axial Mode in that dimension lay.
We can also look at a Graph, and see a big PEAK at some frequency. Simply take our Constant, and divide it by the offending freq, to reveal the culprit dimension!
There. I revealed my Magic. Tuck that in your Tool Kit, and you'll all do fine.
Curt
It was already doable, and might just get better!
Some dips and ups will always exist, as no room is perfect. Interesting is that I for this purpose had bought my measuring mikes more than 5 years ago, but never got to actually measuring until today 
this forum is good for something!
If done right, the room needed to be rebuilt, box in box, etc. but the present is the present, with standing waves and a huge amount of reflections mixed with some damping.
Need to note I "swept" the room quite loudly, so with my normally low listening levels, not all room modes may show up.
Looking at the graph, I find curious:
1. the approx 37Hz = pull down
2. the approx 66Hz = pull down more
3. the approx 500Hz = pull up, but maybe not
4. the area 1kHz-4kHz = raise entire area, if possible
5. the area 6kHz-7.5kHz = drop area, if posslbe
Will this work PEQ-wise?
Questions:
1) How many dB up/down can you adjust the PEQ?
2) What is the Q (Quality factor) of the EQ? The type of eq taking place? or its width from the chosen filter F (Frequency) ?
Stu...
12db +/- on the EQ. Don't even think about boosting anything 12db!
Q-Factor is user chosen directly from the EQ Screen.
Curt
For myself i'd be very careful with eq. i'd go with - or + 3db max aiming to just flatten the curve, with exception like -6 on the 66hz part.
what is the eq Q exactly? In my world it means resonance, but in the eq world?
"Q" is "Quality Factor" Not in the sense of one filter being of "Poor" Quality vs another which is of "High Quality", but rather a matter of Frequency "Specificity"
A High Q filter will affect a very narrow range of frequencies, whereas a Low Q filter is a bit broader in scope. Both filter types (and their iterations in-between) can be very useful to us depending on the task at hand.
Stu, I'm really happy that your thread took this "turn"
You might have noticed that some of us really dig this sort of "Nuts & Bolts" discussion. These matters affect everyone with Speakers, and for every one of us? There's 100 more looking in! The end result is bolstered Activity, and Enthusiasm. How can that be bad?
Good on You!
Curt
Curt962 wrote:You COULD use your existing Mic, but without CAL data for THAT Mic, we introduce uncertainty into our Test Results.
CurtNote the near flat response in the mic specs: http://www.superlux.com.tw/upload/funct … web_en.pdf
Yes, it's accurate enough to measure the 15 dB bumps in our living rooms
Need to note I "swept" the room quite loudly, so with my normally low listening levels, not all room modes may show up.
Looking at the graph, I find curious:
1. the approx 37Hz = pull down
2. the approx 66Hz = pull down more
3. the approx 500Hz = pull up, but maybe not
4. the area 1kHz-4kHz = raise entire area, if possible
5. the area 6kHz-7.5kHz = drop area, if posslbe
Frequency response is independent of level.
One important thing to take into consideration:
The human auditorial system can clearly differentiate between direct and reflected signals, specially from midrange and up.
The measurement microphone cannot, it values direct and reflected the same.
From 1 kHz and up NO EQ should be done based on listening position measurements, because room reflections are largely dominant over direct signal there (~ 80% refl. /20% direct).
In a typical sized livingroom place the mic 60 cm on axis from the speaker, halfway between tweeter and midrange driver.
This represents much better what you hear.
The 500 Hz dip is the typical cancellation from floor reflection, not the nicest frequency to boost (think telephone-sound).
The best way to deal with it is to place the speakers higher.
But tweeters should be 100 - 140 cm above floor, so this "adjustment"' is limited.
Anyway, if ever possible, speaker placement is preferable above EQ to correct room mode problems.
EQ is for fine-tuning.
Remember:
A good loudspeaker can usually be considered as almost linear within its working range.
Changing the EQ changes the response of the 1st wavefront that hits your ear, the direct signal from the loudspeaker.
E.g., if you reduce your 60 Hz peak that is caused by room modes, the first wave front from the speaker will be less impactful in that frequency range.
You will lose your a bass punch.
Hi again Stu!
I neglected to "reflect" (poor word choice in a Room Acoustic Discussion) on your comment regarding Sweep Levels.
Generally, you'd like your Sweep Level to be approx 30db greater than Ambient noise levels. You can measure this easily using the RTA function of REW.
Just position your Mic in your 'Quiet" room and observe the SPL reading. 50db+ is common, thus a Sweep Level would be 80db. It's not hyper critical, but if too high, and we can "clip" the measurement. Too low, and external noises in the Room can influence the data.
80db-ish seems to be a happy middle ground for our needs.
Curt
... thus a Sweep Level would be 80db. It's not hyper critical, but if too high, and we can "clip" the measurement.
Not to forget: typical tweeters can't stand more than a few Watts of continous power.
With sinewave sweeps it's easy to fry them.
80 dB SL is a safe level (~ 1 Watt electrical power), 90 dB can already be too much.
With sine sweeps I usually use 1 Watt, that's 2 Volts into 4 Ohm speakers, or 2.83 Volts into 8 Ohm speakers, if you have a voltmeter.
Defined level makes a measurement repeatable.
A typical room has ~50 dB noise floor if located in a city.
Curt962 wrote:... thus a Sweep Level would be 80db. It's not hyper critical, but if too high, and we can "clip" the measurement.
Not to forget: typical tweeters can't stand more than a few Watts of continous power.
With sinewave sweeps it's easy to fry them.
80 dB SL is a safe level (~ 1 Watt electrical power), 90 dB can already be too much.
With sine sweeps I usually use 1 Watt, that's 2 Volts into 4 Ohm speakers, or 2.83 Volts into 8 Ohm speakers, if you have a voltmeter.
Defined level makes a measurement repeatable.A typical room has ~50 dB noise floor if located in a city.
Note I already did the sweep
edit; @Kais, I measured on the out On my amp output I measured 1 Volts for the sweep, should be doable.
What Speakers are you using Stu?
Just make it easy on yourself.
https://www.roomeqwizard.com/help/help_ … 2075%20dB.
Hi Stu!
I'm back to work in the Caribbean. Yes...it all sounds dandy, but they call it a "Job" for a reason I've come to learn.
We're all still here to work with You. Let's keep the Ball rolling forward shall we?
Best!
Curt
I used to think and still do think that the better the room the less adjustments you need to do thereafter via the eq. I prefer looking into the room but as for every listening situation there are drawbacks e.g. in this case I cannot change the set up of where the listening position is or where the speakers are placed.
The speakers are located on the ear level from the listening position i.e. tweeter not on 100-140above floor but rather 75-80 cm.
Rereading above posts, I guess right assumed that the 67hz spike is a standing wave from the room dimensions and indeed the dip at 450Hz a floor cancellation. It was guessed right that in this room setup the listening position is indeed 2m from a separating glass window, and it is also off center resulting that one of the speakers is close to a corner, an obvious drama. the measurement should prove this.
The spike between 30 or 40 or so, can that be half of the 66-70hz spike? Then it would also be a result from standing waves, one or more.
Reading that the higher fluttering reflections are depending on listening position make me think this should be left as-is.
Given all above my thoughts about the peq setup are now as follows.
1. Take put some dB from the 66hz issue with a narrow freq range around
2. Open for suggestion
Are there even bass traps around for the low frequency which do have a multi dB impact which do not take so much floor space?
Mornin' Stu!
I'm not "guessing" 
There are some elementary Mathematical Formulas that allow one to "model" your Room/Set Up by it's numbers. It's "elementary" because even I can do it, and what else would I do on a Lazy Island Sunday?
The 35hz anomaly, is a function of your Room's 5M dimension. That's the Math. The 65-66hz ish spike is your Floor/Ceiling Boundary rearing it's head. More Math. All stated in an earlier post.
Bass Traps by their very nature are quite large...etc, etc. At 35hz? You're in the realm of Tuned Membranes, etc. You'd better REALLY know what you want before going down that path. How much output do your small speakers really have at 35hz anyway? A quick, and curiously unobtrusive correction for 35hz would be a High Pass filter that is easily created by the RMEs PEQ. Such a Technique is used quite often in Pro-Audio. Broadcasting being only one such example. The benefit to You would be a reduction of LF "muck", as well as perhaps a bit of increased headroom, and lower speaker distortion which comes from asking a Small Speaker to do too much of what it likely wasn't comfortable with in the first place.
All that said, and with such a large number of other things that you say can't be changed, etc, it seems now our hands are somewhat bound.
It's not my gear, nor anyone elses's here so let me ask: "What do YOU hear?" Is there just that "One Thing" in the Sound you wish were improved? Maybe if we endeavor to Slay one Dragon at a time (rather than all at once) we can help you (gradually) achieve an overall better, more satisfying result. Yes? Surely this approach is better than an Acute Case of "Analysis Paralysis" where NOTHING ever happens you would agree.
How's that for beating around the Bush, and not rattling off an assortment of Miracle cures?
Listen. Pick out the ONE thing that bugs you most, and let's focus there.
Coffee time!!
Curt
One topic at a time indeed Note I posted earlier 5x frequency ranges to adjust. Why? Because ADI-2 Pro FS PEQ has 5 bands.
Now for some maybe unfortunate, but I have no issues with my listening environment in the higher frequencies in real life, with note that more acoustic panels are always desired (but if they need to look good they're not cheap). I measured the room especially for this forum.
ONE picked: The 67-ish Hz ... it is actually 66.7Hz
This has fully to do with the room depth of 5.14m, proven by the fact that a 5.14m wavelength corresponds with 66.7Hz. A twice as long wave of 10.28m is thus 33.3Hz. To get rid of this I agree with using a low cut / high pass filter in the PEQ to resolve most quick. Alternative of course is build a HUGE basstrap to kill that low frequency. PEQ is quicker and can also be tuned up and down somewhat to make it work exactly right. And in my experience I'd say, don't overdo it.
For bass counts - at least in my view- that the better it is defined, the less rubble/garbage is present in your audition.
edit: room measurement?
Stu. Show me your Math. 5M does not correlate to 66hz. Unless we're referring to the Null at that Freq likely to occur at 1.25M from the Front/Back Wall.
sounds afaik travels 343m/s. i had to detail out the exact room dim. edited above.
Why bother with theoretical values if there's an option to do measurements?
Changing the speaker/listening position setup seems no option, so...
The effect of room modes does not appear the same at every listening position.
Speaker positioning equally effects, if and how they are exited.
Almost impossible to calculate, unless you use a full-blown acoustic simulation software.
I suggest to do a set of 5 measurements for each speaker, at and closely around the listening position, on ear height.
Left speaker:
Listening position
Left front (40cm ahead and left)
Left back (...
...
...
Right speaker:
Listening position
...
You end up with 10 measurements.
These should be averaged, to give a realistic picture what's really is going on.
Why separate measurements for left and right speaker?
Because you are using a sinewave sweep with your measurement tool.
If both speakers would be used at the same time, heavy comb filter cancellations and boosts appear from 1 kHz and up, due to different travel paths L/R speaker to mic.
This measurement is almost useless.
The alternative is to us to use uncorrelated pink noise for the measurement, this means independent pink noise noise signals on left and right speaker.
My favorite way to measure, besides Time Delay Spectrometry.
The independent Pink Noise from both speakers at the same time mixes without the comb filter effect.
It's even usable in real time during EQ setup, on an Analyser display your software might have.
I looked up above. I asked this before:
Question: how do you measure your room modes and how do you finetune them with the ADI-2 Pro FS per-size EQ? Just play white noise and record it, look at the frequency spectrum and do the opposite adjustments in the EQ? And then one run per side?
Kai, thank you for your kind and clear alternative answer. It would be my favorite!
The alternative is to us to use uncorrelated pink noise for the measurement, this means independent pink noise noise signals on left and right speaker.
My favorite way to measure, besides Time Delay Spectrometry.
The independent Pink Noise from both speakers at the same time mixes without the comb filter effect.
It's even usable in real time during EQ setup, on an Analyser display your software might have.
I have spectrometer / spectogram at my disposal. I am definitely going to give it a try!
Just short summary after which I'd love stop discussing my room modes.
Sweep done with the (buggy!) REW software. Further it is (on mac) unusable with audio cards with count >8 inputs.
Regardless of math or REW-resolved graphs after measuring, the standing wave on 66 something Hz stands (literally) out. Fixing in the room walls/ceiling/flooring would require complete overhaul which I am not in the position to do. It will require a move
...... It might be ADI-2 Pro FS is quicker
I do not intend to connect it via USB can the ADI-2 Pro FS PEQ be set up over USB?
EQ setup can not be remotely done.
There's no USB editing option on the ADI-2 at all.
But ADI-2's EQ setup interface is easy and comfortable to handle, with the three rotary encoders on gain, frequency and Q-factor.
With Uncorrelated Pink Noise on a Realtime Analyser, EQ setup is done in a few minutes.
Just try to bring down the 67 Hz a few dB and listen if you like the result.
My fear is, it will take away too much punch from your system.
Thx
EQ setup can not be remotely done.
There's no USB editing option on the ADI-2 at all.But ADI-2's EQ setup interface is easy and comfortable to handle, with the three rotary encoders on gain, frequency and Q-factor.
With Uncorrelated Pink Noise on a Realtime Analyser, EQ setup is done in a few minutes.
Just try to bring down the 67 Hz a few dB and listen if you like the result.
My fear is, it will take away too much punch from your system.
Regarding 'Uncorrelated Pink Noise on a Realtime Analyser' - is this what REW is used to measure/analyze (in conjuction with UMIK-1 mic)? Or do you recommend something else?
KaiS wrote:EQ setup can not be remotely done.
There's no USB editing option on the ADI-2 at all.But ADI-2's EQ setup interface is easy and comfortable to handle, with the three rotary encoders on gain, frequency and Q-factor.
With Uncorrelated Pink Noise on a Realtime Analyser, EQ setup is done in a few minutes.
Just try to bring down the 67 Hz a few dB and listen if you like the result.
My fear is, it will take away too much punch from your system.Regarding 'Uncorrelated Pink Noise on a Realtime Analyser' - is this what REW is used to measure/analyze (in conjuction with UMIK-1 mic)? Or do you recommend something else?
Sorry, I don't use REW.
Uncorrelated Pink Noise can be found from a lot of sources.
To identify it: it sounds "stereo"-spread on headphones, not like centered in the middle.
Hi Stu!
Back "On" my Work Rotation. You know.. all that Jazz...
Correlated Pink Noise, Sine Sweeps, or Bifurcated Leprechaun Farts, there's lots of ways to "Skin a Cat" so to Speak.
REW uses Sine Sweeps for measurement. and Pink Noise for Levels Calibration. It works good!
The Problem we get into with Full Range 20hz-20khz Measurements is that at higher freqs, even the SMALLEST Mic/Spkr positioning error will result in the most bewildering FR mayhem imagineable. This is because at High Freqs, the Wavelengths become shorter, and shorter. Then, even a 1/4 inch of Postioning Error between 2 Speakers relative to the Mic can result in a virtual Carnival of Phase Related Cancellations. It looks Chaotic on the resulting Graph, and is quite likely to have no relationship to what you actually hear.
To this end, I might discourage "Stereo 20-20" measurements. For Hard Core Work...measure ONE speaker at a time. For my occasional forays into my stuff...I dont even go near that. I may pop off a Sweep only a few hundred Hz wide (in the lower freqs) just to focus on an area of interest. On OCCASION! My Audio time is limited, and I prefer to listen rather than obsessively "test" : ;
Keep it Simple Stu.
Best!
Curt
...My Audio time is limited, and I prefer to listen rather than obsessively "test" :;
Keep it Simple Stu.
This is why I prefer measurement with UNcorrelated stereo Pink Noise on a Real Time Analyser.
You get the full picture from both speakers in realtime (sic!), even changes from the EQ, can drag and place the mic where ever you want, get the result in a minute.
It takes REW approx 3secs to perform a sweep. The resulting Graph displays instantly. I figure I can spare the time.
It takes REW approx 3secs to perform a sweep. The resulting Graph displays instantly. I figure I can spare the time.
OK, that works too, as mentioned I'm not familiar with REW.
It's a Powerful Tool Kai. "Donation Ware" (or Frei/ Verkostenlos) whichever you choose. Widely used in Industry!
Having these test capabilities at one's fingertips in the Home/Studio is virtually MIND BOGGLING were we to consider the cost of such test capability...20yrs ago. Even in the Present Day. WOW!
We had Pink Noise & RTAs almost 40yrs ago in HiFi Shops, and at Home...it's not new. Yes it DOES work...provided!!!...
The user is absolutely SCREWED when they can't interpret the Wiggles, and Jiggles on the Display.
Sure. Let's just start pushing buttons? Ehhhh?? No.
Funny thing...(as I explained to another Forum Member offline today)...
We didn't know what to do with it then!
The Typical Sales Pitch was "See the Graph, then Simply equalize everything" MAGICAL!
WELL! That was BS, and many soon learned that you can throw 1.21 Gigawatts into a 60hz null, and maybe ruin a few Woofers.. but never EQ a Null. I think it was about then that I began opening Textbooks, and studying the Subject.
At the end of this Kai...
REW is something YOU should take a close look at. I suspect you'd love the usefulness of all it offers. It cannot hurt to take a peek
Lastly, We (Yourself and I) can be a useful resource to the RME User Community as a group, and bring forward useful insights to all. Admin tolerates our yammering in hopes of such.
REW? Go for it, and Have Fun!
Best,
Curt
REW is indeed an amazing tool: in a few seconds you can have the first datas, and if you want to go deeper, it is such a powerful piece of software!
It's almost crazy it's free..
And a big community uses this software, you can find a lot of good tutorials (video or text) and a lot of helpers all around the web...
Go for REW fieldstu! You won't be disappointed...
A great pity that REW does not work on Android though - would have made my life easier. Hope to have the funds for an old Iphone 6 soon to get some readings on my room and setup after having for the most part sorted out first reflections with soundproofing. I shall then be back to pick your brains, and some handholding for obtaining measurements etc.
Edit: I am confusing REW with some other calibration software - rew runs on a PC doh.
Mark
Hi Mark!!
I was wondering about you. Hope you're Well!
REW is better suited to PC. Not a mobile app for Smartphone aimed at Car Audio installs.
We'll be here for You! We don't know everything, but we'll surely Dig for answers!
Best!
Curt
Oh!!
For you, and others following along...
Herein lies 530pgs of Valuable Data.
https://www.amazon.com/Master-Handbook- … 0071841040
It's ONE thing to see the Data on REW...it's Quite another to have an understanding of just how it GOT that way!! Fascinating Material!!
I encourage You to get a Copy!
Curt
A great pity that REW does not work on Android though - would have made my life easier. Hope to have the funds for an old Iphone 6 soon to get some readings on my room and setup after having for the most part sorted out first reflections with soundproofing. I shall then be back to pick your brains, and some handholding for obtaining measurements etc.
Edit: I am confusing REW with some other calibration software - rew runs on a PC doh.
Mark
I don't know if I mentioned it to you, I did elsewhere:
On iPhone AudioTools by Andrew Smith, the FFT-part of the suite, is by far the best Audio Analyser solution.
It uses iPhone's internal microphone in a special, calibrated "measurement mode", so no additional hardware needed.
There is a free 14 day try-out available.
https://apps.apple.com/de/app/audiotools/id325307477
Hi Curt, and Kais,
Hope you are both well. Think I will get a copy of that book - could be most handy.
Kais - as soon as I can will be getting the iphone, and the software, and be back for your help with it. Lol.
Mark
Herein lies 530pgs of Valuable Data.
https://www.amazon.com/Master-Handbook- … 0071841040
It's ONE thing to see the Data on REW...it's Quite another to have an understanding of just how it GOT that way!! Fascinating Material!!
Valueable read!
It is good information indeed. Regardless of what your measurement system is, some background to help put the Jiggles, and Squiggles into context is useful.
Curt
PS: You should've given this a Whirl 35-40yrs ago. Oh my! Sitting there with a Test Record, an SPL Meter, and a piece of Graph Paper. Imagine if you will...the BEST "Ben Stein Voice"
"....FIFTY.......Herrrtz"
Brrrrrrrrrrrrrrrrrr
And then on to the next Freq. Man! It took awhile!!
It didn't matter anyway. If our Data was at odds with the (purely Subjective) Magazine Review, then clearly our Data was in error! (The thinking was: "You can't measure Sound") But you can always spend more Money! Surely then some better Capacitors, Cables, or Boutique RCA Connectors would correct the problem. Most often, neither the Room, nor the Set Up was ever considered. The BRAND NAME of the Gear was the determining factor. Oh...the Foolishness of it all. 
> The BRAND NAME of the Gear was the determining factor.
Nowadays don’t we sometimes do the same?
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