Old school stereo system tonal improvements without EQ or DSP

[thewas]

An option to attempt when someone does not have an EQ or DSP in his (usually classic stereo) system and the placement options of the loudspeakers are limited:

1. Do separate left and right moving microphone method measurements around the desired listening position.

2. View those with some strong smoothing like 1/3rd or psychoacoustic to see the main deviations from the desired target.

3. Experiment with the amp or loudspeaker tone controls as well fully or partially closing the bass reflex ports of the loudspeakers.

4. Re-measure, re-adjust and listen till satisfied.


An example of a pair floorstanding loudspeakers stock vs. the final adjustment, in this case closing the ports and setting the amp bass and treble to both +2 setting vs a -1 dB/octave target which sounds natural in that room with those loudpeakers, left side

and right side

Of course measurement-wise the perfection of a DSP or set of PEQ cannot be reached but the result sounded better than I would have expected (and more natural than many strong auto-EQ filters, probably due to the low Q-factor of the filters, avoiding over-correction and the less steep low bass roll-off due to the closed ports.

 

[Chazz6]

What is a low Q ?

 

[Steven Holt]

i won't argue with thewas, but the first thing i would do is wire in a subwoofer. subs do amazing things with older systems.

 

[xanalog]

Thank you for the post, @thewas,

Honestly speaking, I have had zero interest in using a DSP or an EQ in my systems, digital or otherwise.
I have rarely (if ever) even bothered with tone and/or the loudness controls.
I have even parted ways with my multi-channel (=separates) attempts and their costly divorces.
I have even failed at my attempts to discern any differences between those six digital filters in the latest ESS Sabre DACs.

I am perfectly happy with a nice pair of floor-standing (full range) speakers that measure very well and are able to provide a modicum of a balanced soundstage for two people, sitting 3 feet apart... after spending some time to minimize the room effects. Competent/tested power-amp, pre-amp and a DAC are my only other requisites.

I guess, that is the 'Old Skool' I am most at-home with.

 

[Keith_W]

What is a low Q ?

Here are two PEQ's with centre frequency of 1kHz and gain of 5dB. Red curve: Q = 0.3, green curve: Q = 2.8.

Higher Q = more "peaky", lower Q = more gentle.

 

[thewas]

i won't argue with thewas, but the first thing i would do is wire in a subwoofer. subs do amazing things with older systems.

It should be said though that in a classic stereo system it isn't trivial to get a smooth response with them (unless the sub has its own measurement based DSP) and in above example case even without subwoofer 30 Hz were reached which is quite deep. Subwoofers of course can increase the total SPL of the system and even fill room related bass dips but as said their integration (also spatially in normal living space) often isn't trivial.