I just today noticed something about GLM.
Basically the sound character profiler only works on the monitors. It does not touch the subs. I don’t understand this. I’m sort of upset that it works this way. What’s the point of profiling the sound characteristics of it doesn’t change the associated subs?
Now I also wonder if I were to overlap the crossover points. Say I let my mains go down to 50Hz and let the subs go up to 70Hz. Will it compensate for that?
The lack of a holistic control on the top is very irritating for the home listener. The lack of holistic compensation of the subs with each other and the monitors is also irritating.
Yes it adjusts levels overall but will it apply a filter to any overlapping frequencies? Then allow for a top level preference? The former - not sure. The latter for sure - no.
Let’s not even get into if it will use one sub to fill in for a dip on another sub if that sub is in an acoustically favorable position to compensate for the other sub which could be in a unfavorable position for that frequency.
When is this all going to be implemented. They know by now many of us are using these for listening.
Please see that SCP is only applicable to the monitors themselves.
EDIT: after expressing my “outrage” I realize tangband’s suggestion to just manually play with the filters is the only way to go. Just do it yourself. Don’t count on SCP raise the subs.
For really outstanding sound results, yes - You cant rely only on the measurements. The corrections that GLM make can be to big or to small. You listen not only with your ears, but also with your mood and your eyes. The eyes sees the room and expect it somewhat to sound like a room, not outdoors. Roomcorrection must be done with care.
Heres one way to do this:
1. Always set up the two front loudspeakers in the room on proper stands about 60 cm high, ( 8341,8340 ) where they alone can play very good bass tunes with real music without any GLM corrections and without subwoofers.This is very important. Play with the distance to the front wall and the distance between the two speakers. Listen from the listening position using music.
2. Then put your two subwoofers on the floor, on the direct inside of each L and R speaker. After this - do the GLM measurements with the mic at exact ear position, and at the listeningposition using a microphone stand . Use only one correction spot in GLM !
3.Try listening with autophase, but also without autophase. Try the same crossover frequency OR try slightly overlap or underlap. Try putting autophase to 0 degrees and try different values.
As an example of underlap or overlap: 60 Hz LP and 65 Hz HP, or 70 Hz LP and 65 Hz HP . Use the best sounding setting by listening to the bass tunes with real music playing.
The GLM or any other room correction program cant decide whats tuneful in the bass area or not. We as humans are musical and programs and computers are not.
4. Gain optimisation must be correct and you do this when you are saving everything to your loudspeakers. I suggest setting the GLM drawbar to -30 dB as a start. Save it into the speakers. This way you can use a digital DDC ( computer or Yamaha wxc50 ) or analog source preamp with some volume regulation at the source, also airplay without any big sound penaltys. Its always better to feed those GLM monitors with a loud digital signal or analog signals, so the dsp can work without to much truncation and loss of data. The volume drawbar in GLM works AFTER the dsp.
5. Dont expect that the default crossover frequency at 85 Hz will sound the best. With my gear ( 8340 and 7350:s ) the sound is best with a crossover at 55 Hz in my listeningroom. You can change the crossover settings at any time (Edit) without doing a new GLM meaurement. Try sound caracter profiler and try print - 3,5 dB from 100 Hz - meaning that you lower everything from 100 Hz and above that frequency.
6. After some hours or days deciding what sounds best by ear, listening to bass tunes, fine tuning the settings - save everything into the speakers ( dont forget to set the gain drawbar to -30 dB ) and then put away the GLM kit.
7. Now you can do some interesting comparisons - you can switch the dip switch STORED on the back of each L/R speaker , and compare the sound with or without STORED (stored=GLM , off = no GLM correction. )
The sound should be better on all accounts with the switched STORED on, If its not, you have done something wrong with the GLM setup.