This is an OK active crossover, and the price is quite appealing considering its features. However, it sounds harsh at the crossover point. I had it set up with a 2.1 home audio setup consisting of 1 sub, and left and right channels consisting of 1 woofer and 1 tweeter each. All 5 of these speakers are driven by separate amps, and I was using this Soundstream device for the active crossovers. Before using this Soundstream device I was using a custom-made 4th-order Linkwitz-Riley active crossover circuit that I built myself (I am an electronics engineer). This crossover I made has worked quite well for several years, but its noise floor is pretty high, resulting in a lot of white noise when the volume is turned up. I was trying to eliminate this problem by switching to the Soundstream crossover.The problem with this Soundstream crossover arose at the crossover point from the woofers to the tweeters, which I wanted to set to 3 kHz. When setting the woofer LPF and the tweeter HPF both to 3 kHz, the output sounds bad around 3 kHz. On some songs it's downright painful to listen to, and on most it is at least somewhat fatiguing. If I lowered the LPF frequency and raised the HPF frequency, the harshness was reduced, but now there was a gap in the frequency response. The problem still occurred when changing to other crossover frequencies, and happened at all output levels. This issue was not present at all on my custom-made crossover circuit, and overall my circuit sounds a lot better. The only advantage that the Soundstream has, sound quality-wise, is that its output has much less noise than my circuit.If you're not too picky about sound quality, this harshness at the crossover point might not be an issue for you, but over time you may come to notice it if you're used to high-quality sound systems.In terms of features, this Soundstream crossover is pretty good, but not great. Having 4 crossover bands plus an unaltered line-level output provides lots of flexibility, especially compared to 2- or 3-band crossovers. Mute and volume control on all outputs is also good to have.Some features it lacks are:- For the sub, there are L & R inputs and L & R outputs. The only way to combine the inputs into a mono signal (which is important if you only have 1 sub) is to make the entire audio chain mono. So, the signal going to your main speakers will also be mono. It would be much better to put that mono/stereo switch on just the sub's audio path, rather than where it currently is, right at the main input.- The mid-low and mid-high outputs have to be bandpass filters. You can't set them to just use a LPF or just use a HPF: they must use both at all times. For example, if you want an output that has a HPF at 80 Hz, and no LPF (perhaps because you're driving a speaker that already has a passive crossover), you can't do that.Overall I wouldn't recommend this active crossover due to its sound quality issues at the crossover point. If you're not picky enough about sound quality that you won't notice this issue, then you probably shouldn't be putting in the effort to set up an active crossover system; you may as well just use passive crossovers. If you are picky enough that you want an active crossover system, then you will probably notice this issue. I will be returning mine and looking for another option.

Crossover points are designed for adding more to the highs and leave a a large gap if you were hoping to shape the sound of your systems low end. I managed to make it work using the passthrough and , but would have preferred to see the crossover points less restrictive.

It's ok dont see much difference in the midbass but overall a decent price and piece..

The buttons are Stuck inside the case and will not come out very poor for the money!!! Waited three weeks for it to be delivered for it to use it in 10 days time Have to spend money to get it fixed

This product works great . If you have alternator whine or anything like it this product will make it more pronounced so know that going in . This is absolutely great for the price soundstream is known for winning all sort of awards for there processor and crossovers I have been very surprised by there stuff so far I am 25 yes in car audio I run about 8000rms system hdx12 s sound qubed and 8000.1 vulcan stetsom the subs and amp both have surprised me with how great they are the stetsom is a beast and you must have a ho alt and battery bank to keep up with it but well worth the investment if you want to shake cars 10 ahead of yours buy this crossover and a stetsom amp wowwwww!!!!!!!!

I spent $2k on a Pioneer HU/Amps and Cerwin Vega speakers. It sounded "hollow/tinny". I added this to separate all of the freqs. Can still use the HU to make adjustments instead of going to the PROX4.1. So, if you have separated highs, mids, and lows, this is HIGHLY recommended.

this is a nice old school analog x-over. i realize that in today's age of DSP wizardry this technology is on its way out and almost dinosaur status What can I say.... I'm a 50 YR old former car audio installer/store manager (first career after high school) turned professional pilot. this analog gear is my speed. i like the fact you tune it with a screwdriver rather than a keyboard. today I am building myself a high end system as I would have built , when I was a kid, if I had the money. I like this X-over for its simplicity and honesty. you look at it and it makes sense. when the system is all the way done i will comment on the sound quality of the unit but right now things are looking good. The act of building the system is a joyful trip down memory lane for this old pilot who spent many years building other people cool stereos when he was a young man.

I purchased the Soundstream PROX4.1 Bass Reconstruction Processor a few months ago and have been blown away by the sound quality and hard-hitting sub-output. It's an incredible product that has transformed my car's audio system.However, I have noticed one issue with the Mid-High right output, which produces a consistent hissing sound (just started). It doesn't impact the overall sound quality, but it is noticeable when the volume is turned up. I've contacted Soundstream customer support about the issue and am hopeful they will be able to resolve it.Despite this one issue, I still highly recommend the Soundstream PROX4.1 for anyone looking to upgrade their car audio system. The amazing sound and hard-hitting sub-output are truly impressive.Overall, I am very satisfied with my purchase and look forward to continuing to enjoy the incredible sound quality of this product.Hope this helps!