Sundown Audio: SXMP-6 and SXMP-8

Again, it’s all about the punch and volume

Producers of the “variety” seem to be gaining momentum in the battle for the midbass. It is more enjoyable to have a system that reproduces all the range and doesn’t sound “like” from a phone with a subwoofer. You have to give it a try to get the punch and tight hit you want. Sundown Audio is the target audience for this move.

• DESIGN

Two Sundown Audio SXMP series speakers were tested simultaneously – 6.5 inches and 8 inches respectively. They stand out against the background of most of the “variety”, at the least, with more serious performance – cast pans, large magnets and an unexpectedly good weight.

Both motors have large motors of similar dimensions. Magnesia’s magnets measure 135mm in diameter. The magnets do not have an axial hole so you don’t need to leave any space behind them. You can count this as an added plus.

Variety Speakers Test

The 8-inch model is the same as the standard, but the hole diameter for the 6.5 inch speaker is slightly larger than that of the standard. It will not cause any problems during installation. You just need to consider it when making rings.

Both speakers’ diffusers are made from medium density pulp, but they have a slightly different texture to the front.

Two-wave top suspensions allow for a greater linear travel than traditional “pop” speakers. We must remember that this is a mechanical movement. The voice coil’s proportions also determine the stroke.

Both speakers’ diffusers are made from medium density pulp, but they have a slightly different texture to the front.

Two-wave top suspensions allow for a greater linear travel than traditional “pop” speakers. We must remember that this is a mechanical movement. The voice coil’s proportions also determine the stroke.

I want to draw your attention on an important detail: the thickness of magnetic circuit washers. Her height is 8 mm. This is thicker than most pop speaker. A thick washer simply means that there is a large magnetic gap. This also means that the coil’s working length is longer. This motor has a better stroke linearity and the amplifier can better control the speaker.

The only problem with this design is that the magnetic flux is “smeared” across a larger area than the magnetic gap. This means that stronger, more expensive magnets must be used. In reality, both speakers show the same thing.

• MEASUREMENTS

These speakers are extremely powerful and have very strong motors. They have high BL, low electric (and, consequently, full) quality factor, and high sensitivity.

Short-circuited turns, also known as Faraday rings, are used in motors. They reduce the back EMF generated by the voice coil when it moves in the magnetic gap. This reduces intermodulation and transient distortion. The sound is clearer at higher volumes.

Sundown Audio SXMP-66.5: Impedance versus frequency

• Sundown Audio SXMP 6.5 measured parameters
• Fs (natural resonant frequency) – 110 Hz
• Vas (equivalent volume) – 4.1 L
• Qms (mechanical Quality Factor) – 4.53
• Qes (electricity quality factor) – 0.41
• Qts = Full Quality Factor – 0.38
• Mms (effective weight of the moving system), 12 g
• BL = Electromechanical coupling coefficient – 8.4 Tm
• Re (voice coil DC resistance) – 3.4 ohms
• dBspl (reference sensitivities, 1m,1W) – 93.4

Sundown Audio’s SXMP-8: Impedance versus Frequency

• Measurable parameters
• Fs (natural resonant frequency) – 86 Hz
• Vas (equivalent volume) – 13.5 liters
• Qms (mechanical Quality Factor) – 5.49
• Qes (electricity quality factor) – 0.49
• Qts = Full Quality Factor – 0.45
• Mms = Effective Mass of the Moving System – 17 g
• BL (electromechanical coupling coefficient) – 8.1T m
• Re (voice coil DC resistance) – 3.4 ohms
• dBspl (reference sensitivities, 1m,1W) – 94.6

It is important to note that the resonant frequencies of “pop” speakers are very low, but it is possible to get some punch with them using such a range of parameters. The design will need to be rethought.

You can’t just install speakers in doors or large cabinets if the decay is too frequent. Speakers will sound more like midranges than indicate and have a slight hint of punch.

These parameters allow for lower dynamics. A phase inverter is all that’s needed to make these parameters work lower. Consider this: A 6.5-inch SXMP-66.5 plugged into a 3 liter plug, and the same 3 liters with a 110 Hz port. What will the difference be?

Frequency response of Sundown Audio SXMP 6.5 installed in various acoustic designs

• Blue – ZYA, with a volume 3 liters
• Red – FI3 liters/110 Hz (diameter 4, cm, length 7cm)

This is especially true for those who are still not cleared the chip. Three liters (!!!) Only three liters (!!!) The 6.5-inch “stage”, regardless of what anyone may say, will work most efficiently between 250-300 Hz. SXMP-6.5 is very appealing against their background.

The 8-inch Sundown Audio SXMP-8 can be enhanced with a phase inverter to deliver a stronger punch and bring the speaker closer to the subwoofer’s frequency. It all depends on how loud you want each speaker to be audible. The best options are found in cases between 15-20 liters.

You could try using doors to do this. The average volume of a door is only 30-35 liters, which is the maximum for a pair speakers. However, you will need to work hard to make the “tin” a sturdy case. It’s complicated. It’s complicated, but just think of the impact it can have.

Sundown Audio SXMP-8 frequency response in various acoustic designs

• Blue – ZYa, with a volume 10 liters
• Violet – FI 10 Liters / 90 Hertz (diameter 6cm, length 5cm)
• Red – FI 15 Liters / 90 Hertz (diameter 8cm, length 8cm)
• Green – FI20 liters/90 Hz (diameter 10, cm, length 5, cm)

CONCLUSIONS

These speakers were complex and had many hidden features. They will sound great if you place them in the door like normal midrange speakers.

If you think outside the box when designing the system, you can get them to play lower and pack a punch. The physics of this is straightforward: If you require a return at lower frequencies, you can only “push” the air one of two ways. You can either increase the diffuser stroke (with the inevitable decrease of sensitivity) or use a phase-inverter design. There are no other options. Sundown Audio took the sensible decision to go the second route. As with all stage acoustics producers.

The SXMP series acoustics is for people who want a loud system with full mid-bass range and are willing to go above the “door” installation.