I have the stackables. You have to use (at least on my 2 wildcats) both end pieces (your 1 and 6) and any combination of the middle baffles.
For me, I find the .22 shoots acceptably quiet with section 1,6 and 2 baffles ( estimate 40 yards between shooting position and someone that might complain). That config is only 1/4 inch shorter than the Huggett Belita. The full 6 piece set up of stackables is about 3/8 inch shorter than the full size Huggett.
There is only 2-3 dB difference between Belita and Full size Huggett. Measurements with class 1 SPL meter using C weighting and fast response from 7 feet front and rear 45 degrees off axis averaged over 5 shots front and 5 rear. Measurements taken today to support your inquiry.
Wildcat .22
- Full size Hugget 61 dB
- Belita 63 dB
- 6 piece stack 67 dB
- 4 piece stack 70 dB
I generally use the Huggetts in either size to shoot. It is 20ish yards from my back door to neighbor's back door with zero complaints or inquiry. The Belita only adds 4.75 ish inch to the end of your shroud. Not a bad trade off. Either Huggett is pretty impressive on this gun and is a good fit with overall length, weight, diameter. There are quieter products available from DonnyFL (I have several) but in this particular case, they are overkill with much larger "foot print" off the end of a small wildcat.
For subjective level human psycho acoustics, a “feeling” of perceived level of double the sound output, the industry norm for this is expressed as 6-10dB. This “feeling” or human perception is not an exact measurable value.
The audio industry utilizes the inverse square law to calculate attenuation of sound over distance. A doubling of the distance from a noise source will reduce the sound pressure level by 6 dB. Using this attenuation model and assuming my neighbor had their back door open, the sound emanating from my Wildcat would be below the ambient sound floor at their house (think a/c, tv, fridge, conversations, etc).
