# Interpret this spectrogram please



## Bear123 (Dec 31, 2013)

Hey everyone. Here is a spectrogram of my subs. I am just not entirely sure how to read it as far as what is good, what is bad, and what it is really telling me. Any expert tips?


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## MPS (Nov 4, 2009)

Looks pretty good and smooth maybe little bit "hot" from 40Hz down?


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## Bear123 (Dec 31, 2013)

I have a 6 dB house curve starting at 50 Hz extending down to 20.


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## Wayne A. Pflughaupt (Apr 13, 2006)

Waterfall and frequency response graphs are much more useful, IMO. 

Regards,
Wayne


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## MPS (Nov 4, 2009)

Bear123 said:


> I have a 6 dB house curve starting at 50 Hz extending down to 20.


Ok, that's why onder:

I would personally prefer few dB up from ~120Hz to ~40Hz and then down to normal level again. It's a matter of opinion anyway. Did you try various settings or how did you come to this setting?

Your low frequency spectrogram looks very smooth, how is the waterfall and RT?


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## Bear123 (Dec 31, 2013)

Here is the waterfall. I have some issues above the crossover 80 Hz plus that I am having trouble with. I am thinking YPAO is just not doing much to help....I have a bit of a peak at 100 Hz that I can't seem to change with phase, distance, or crossover. I might try to do some work with the limited(7 band) manual eq to see if I can get it closer, but I think either a good add on manual eq (maybe I can use my miniDSP) or an XT32 receiver might be in order:


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## Bear123 (Dec 31, 2013)

Full range FR and sub FR:


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## MPS (Nov 4, 2009)

Problem is that when you ask other people's opinions, you get other people's opinions.

Here is mine anyway:

Your LF looks smooth but I don't like rising trend at lowest octaves. This makes bass heavy. Typical for showing off and easily impressive but not so good for natural timbre of instruments. Might work for movies though. 

Some lack at lower midrange takes off "body" of voice but promotes clearness. Your LF level is extreme, do I see 20 dB rise? I think from about 200Hz to 4kHz it should be quite flat (maybe 3dB down if you prefer warmness). Did you measure with multiple channels? Lower HF ditch might be result of the interference between channels and is not reliable way to measure anything else but LF. Please use 1/12 octave or less smoothing for analysing.


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## Bear123 (Dec 31, 2013)

Just looked closer at my full range FR and yeah I think I might have had the subwoofer channel jacked up 12 dB as I was about to do a max output sweep with the subs and didnt want to take the MV to +10. I will run some more sweeps with calibrated subwoofer levels. I run them hot but not that hot lol.


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## Phillips (Aug 12, 2011)

Find the best position for your mains both left and right, and both subs + listening postion using REW RTA (real time analyzer), RTA saves doing several sweep measurements.

Yamaha YPAO big down fall is the bass, so the manual EQ will be an advantage. YPAO otherwise does a great job with my experience. There are options. 
What model of Yamaha do you own?

How does your high end sound?
Then measure using sweep to fine tune
Level match all below speakers/subs

Post the following once above has been measured at the LP and dealt with etc.
left main
right main
both left and right main combined
sub 1
sub 2
both subs together


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## Bear123 (Dec 31, 2013)

RXV-375. Should I run all those sweeps prior to YPAO and after YPAO to see if it is helping much? I don't think there is a way to incorporate my miniDSP into the system to eq the speakers, but I did run my FR through REW's eq program for miniDSP and the projected response came out very flat. 

Have not used RTA yet so thanks for the tip I will give that a shot this weekend.


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## Phillips (Aug 12, 2011)

> RXV-375. Should I run all those sweeps prior to YPAO and after YPAO to see if it is helping much?


Wouldn't hurt.

Would pay to find the best positions for everything with YPAO off, letting YPAO do as little as possible to deal with. Post your findings.

I own a Yamaha Z9 great receiver. I also own a DSpeaker Anti Mode Dual core which Eqs the mains, does a great job. The subs are Velodyne Digital Drives which have there own Eq, also great.



> I don't think there is a way to incorporate my miniDSP into the system to eq the speakers, but I did run my FR through REW's eq program for miniDSP and the projected response came out very flat.


Not familiar with Minidsp.
Always remember it is only projection though reasonably accurate



> Have not used RTA yet so thanks for the tip I will give that a shot this weekend.


You are welcome,yes it is a quick way to measure with fine tuning with the sweep measurements


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