After a period of additional listening tests and by request of DIY builders, I here describe more tweeter tuning options for the Prestigious Two – Monitor DXT loudspeaker. The original version could sound a bit to warm or light dark at times depending on which stereo equipment where used or how the loudspeaker was placed and toed-in etc.
All the options below are technically equally good and the phase behavior and phase tracking around the cross-over frequency are not compromised at all compared to the original version. The large amount of tweeter padding options are available so each and every one can find their own setting that fits their personal tweeter level preference and taste in combination with their HiFi equipment, room interaction and setup.
I urge everyone to buy a couple of extra resistors for this build and try out some of the tweeter options. It really pays off, since what seems to be a small change in the frequency chart can be could be a significant difference that works out in your setup.
In some of the options the actual cross-over frequency is lowered compared to the original version and it’s perfectly normal, since the lower treble output is higher in these versions, but the configurations are carefully chosen in order to have optimal phase tracking around the cross-over frequency. You can see the phase tracking effect of the different tweeter level options by looking at the “reverse null” charts, which all show a very deep null as they should and it indicates a good phase behavior around the cross-over point.
All frequency charts use a 1/24 octave smoothing and are based around the 15deg off-axis measurements. The grey reference line (83dB) is used in order to easier see the effect of the different tweeter level options.
The resistor R1 is used to change the upper treble level from 8kHz and up and the resistor R3 is used to change the lower treble to mid treble level.
(click on picture to zoom)
Upper left: R1=1.5 Ohm R3=4.7 Ohm
Upper right: R1=1.5 Ohm R3=4.7 Ohm “Reverse Null”
Lower left: R1=2.2 Ohm R3=4.7 Ohm (Original version)
Lower right: R1=2.2 Ohm R3=4.7 Ohm “Reverse Null” (Original version)
3kHz cross-over frequency. The R1=2.2 Ohm option shows a deeper reverse null.
(click on picture to zoom)
Upper left: R1=1.5 Ohm R3=6.8 Ohm
Upper right: R1=1.5 Ohm R3=6.8 Ohm “Reverse Null”
Lower left: R1=2.2 Ohm R3=6.8 Ohm
Lower right: R1=2.2 Ohm R3=6.8 Ohm “Reverse Null”
2.6kHz cross-over frequency. The R1=2.2 Ohm option shows a deeper reverse null.
(click on picture to zoom)
Upper left: R1=1.5 Ohm R3=8.2 Ohm
Upper right: R1=1.5 Ohm R3=8.2 Ohm “Reverse Null”
Lower left: R1=2.2 Ohm R3=8.2 Ohm
Lower right: R1=2.2 Ohm R3=8.2 Ohm “Reverse Null”
2.5kHz cross-over frequency. The R1=1.5 Ohm option shows a deeper reverse null.
(click on picture to zoom)
Upper left: R1=1.5 Ohm R3=10 Ohm
Upper right: R1=1.5 Ohm R3=10 Ohm “Reverse Null”
Lower left: R1=2.2 Ohm R3=10 Ohm
Lower right: R1=2.2 Ohm R3=10 Ohm “Reverse Null”
2.4kHz cross-over frequency. The R1=1.5 Ohm option shows a deeper reverse null.