DSP-408 4 Input 8 Output DSP Digital Signal Processor with Built in EQ Crossovers, Time Alignment, and in-Put/Output Mixing for Home and car Audio

Needed to boost up the low end of my car subwoofer. Without it my sub just made the bass louder and a little less defined, with it i can set a very low crossover for my sub, lower than my amplifier or head unit allowed for, and eq boost at 23hz. System has the depth and balance i want now. Will probably add a 4 channel amplifier and really dial in the sound of the rest of the system later. The matrix signal mixing system could be confusing, but it's legit. Lots of flexible possibilities! One thought I had for a car setup you could create from just left and right input; you could create active 3-way front left and right speakers using 6 of the output, down-mix to mono for a single channel rear-fill, and down-mix a sub-woofer channel as well! Awesome! Another great feature, the DSP-408 let's you group output channels so you can apply equalization and filters in unison, a feature i wish Mini-DSP had! Very happy with the unit. Pros: Cool signal mixing system! 6 band parametric equalization per output channel. 6db/12db/18db/24db selectable high-pass and low-pass filters for each channel. Strong 3.5 volt RMS Output. Smart phone configuration with Bluetooth accessory. Good build quality (some sharpish edges on aluminum engraved logo) No turn off noise or POP! Low Price! Cons: Some slight turn-on noise. (very low) Some sharpish edges on aluminum engraved logo.

Despite using high end components, my car stereo had some dead spots in it where it just sounded flat. I tried several different approaches and then is dawned on me- I used a DSP for my other systems at home (dbx driverack) and they solve problems, so I ripped out my AudioControl components and started over with the Dayton DSP The windows app is fine- it’s simple and makes sense. I honestly can’t believe people complain about not having a flashy app with skins etc- it’s just a tool for setting up your rig. Thank you for NOT making some silly bling app. The capabilities are exceptional and everything works exactly as expected. The sound is clean and clear, and it can do everything I need. Now, thanks so a calibrated microphone and an RTA app... it’s finally a good sounding system. If they wanted to take it a step up, I’d appreciate a sub harmonic synth or a BBE type processing ability or license AudioControl’s much sought after ESP2 and build in the capability. I’d put one in all my cars if they added those features. All in all,I absolutely love this DSP- it’s finally made car audio SO much easier. Anyone can now have a killer system if they take the time to set up properly. My system: Chevy MyLink head unit, Dayton DSP, Alpine Amos for sub and fronts, stock Boston Acoustics amp for rear speakers. All Polk MM components & Polk MM 10” sub. AudioControl ESP2 and Epicenter.

4 stars because alternator whine. That said, this is not designed for automotive use using the RCA inputs. The RCA inputs are unbalanced and will not work with a preamp. My solution was to use a preamp that has 4v balanced outputs and feed that into the high level inputs and turn the gain up a bit. Worked flawlessly to get rid of the alternator whine and hiss when the engine was off. Once the noise floor issues were solved in my mobile environment, tuning was next. Pro tip - the bluetooth adapter is great for getting audio into the unit, but the app is f*** trash. You need a laptop to program this thing. Once you get the software running on a PC and plug in, its very simple to tune. Took 5 minutes to get this thing sounding perfect with my computer, and 10+ hours trying to get it to work with my phone. Just use a PC. Once set up correctly, it brought my system to life. Concert quality audio, not even kidding. The before and after is incredible - when I disable everything and make it sound original, it sounds like you have water in your ears (my radio sucks) but once tuned, nice and crisp. The crossovers for the low end actually work - and well for that matter. Bass was muddy using the built in crossover in my amp. Got this thing set up and just wow. I didn't know my subs could hit that low, or high. Woke my system up.

I wanted a stealthy system but the AudioControl DQ-61 eq that I had previously is controlled by knobs so I Installed it in the glovebox compartment. I didn’t like this setup. I replaced it with the Dayton dsp-408 because it is small enough to be hidden away under the dash and it has bluetooth and it’s cheap. The other dsp with bluetooth easily cost double. I used to have the factory deck > AudioControl DQ-61 goes straight to the > amp. Now I have deck > AudioControl Lc2i > DSP-408 > amp which costs about the same but sounds much better. However, most of the time I use a LG V20 phone with quad DAC connecting straight to the dsp, completely bypassed the deck and the lc2i. This method sounds best. I only use the deck/lc2i for phone calls or when I don’t have the v20. By the way, don’t use the dsp-408’s speaker wire input (doesn’t sound good), use a quality active loc like the lc2i instead. Controlling my dsp unit via app is much better than via knobs. It’s much more precise which resulted in clear separation between speakers, sounds, frequencies. My 10 inch sub never sounded better before. I clearly have a sound stage now and I can position it precisely. I really enjoy music in my car now. I agree with others that the phone software is kinda weird but once you understood it becomes non issue. I liked it so much I actually got a second unit to replace in my other car. Both systems sounded a few times better and I am happy not having to spend a fortune but able to achieve decent sound, style, convenience. I recommend you trying out this unit before spending more $ upgrading your speakers, sub, amp, etc. you’ll be surprise how good your already existing system can sound. Just make sure you run 100% oxygen free cooper wire throughout and solder whenever you can instead of crimping. That’s it nothing fancy and you can thank me later.

I purchased this this unit to replace a different brand DSP that was introducing unwanted distortion. I had read reviews on this unit and saw many mentions of background hiss or a hum typically caused by a ground loop (poor grounding). I thought maybe these people hadn't taken the proper steps to ensure they had a properly grounded system or they were using cheap RCA cables. I connected the unit in place of my previous DSP which was a cheap unit but had no noise issues. The sound quality while my vehicle was off was excellent and I had no background hiss or noise. I messed with some settings via the PC program and its very easy to use. Unfortunately this was short lived after starting my vehicle. There was a constant low frequency hum and a high pitched whine that increased in frequency when my engine RPM increased. I decided to try some troubleshooting to verify there was no issues with my install. I decided to run a temporary ground and power line directly to the battery just to see if it would help. It did not. Even though I know my connections are very good I decided to go through all of my entire system and verify everything was still secure. (I really wanted this DSP to work) I found no issues with my system connections. I read in one review that someone "resolved" the issue by removing the REMOTE IN connection and having the unit turn on via the RCA signal. Again, no change. I even ran a temporary set of RCA cables with no change at all. When I removed the unit from the signal chain completely there is absolutely no noise at all. I'm fairly certain the issue is not on my end. My system consists of a Pioneer Head unit, Rockford Fosgate amplifiers, Knukonceptz Krystal RCA cables, and Knukonceptz 0 gauge OFC power from the battery to both amplifiers and the alternator and dual 0 gauge grounds on my battery with brand new battery terminals and a new battery. All ground connections have all paint removed and are connected with a gold plated terminal blocks and I apply an electrolytic compound between the terminal block and vehicle that improves and protects the connection. I understand a device maybe being limited in options because it has a lower price point. However I can't understand how a device could be sold with this kind of issue and it hasn't been addressed with an improved design. I would be more than happy to pay an additional $50 if this was resolved in a redesign as it would still come in much cheaper than most other DSP's. PROS: Easy to install, easy to setup and control, great sound quality. CONS: Overpowering hum and whining noise while vehicle is running unfortunately makes this unit unusable for car audio. 😞

Tariffs have made the miniDSP 2x4HD ridiculously overpriced so I tried to go this route to align a pair of SVS subs for my home theater. Wrong decision…. Pros: - SUPPOSEDLY offers a 10 frequency PEQ which seems like it would be quite customizable. - ~$200 cheaper than an equivalent miniDSP product (but there’s a reason for that) Cons: - Interface is awful - Only works with PC’s unless you spend another $60+ for a bluetooth adapter - Couldn’t get the settings to be loaded into the DSP even though the interface said it was connected - Delay limited to 8ms (knew this before buying it, but it’s still a big negative that people should know about) -Seems to get really warm, and that was just when I was trying to program it

Anyone who values good clean audio needs a DSP, very straight forward to setup, the PC based software is very easy to use, user manual is is very good ( not included, must be downloaded ). The 10 band PEQ per channel is very nice with adjustable Q. Time alignment is a game changer and the ability to assign each of the four channels in to any or all of the outputs is great. Love the presets. The only down is the mobile app, it could use some work, it is nice you can quickly change the presets and stream via Bluetooth ( $30 bt adaptor need ), you can also get a $20 remote that allows you to control master volume and change presets only. But for any EQ tuning is way better on a laptop. It does include a ac adapter if you use it for home use or want to bench config. Has speaker level inputs but after testing I found using a quality LOC and using the RCA inputs sounds much better, you get about 2.5~3v out on the outputs, would love to see 4~5v on those outputs. This has allowed me to go 8 channel active in my car with a great sound stage, after tuning with a good RTA and setting my amp gains I was blown away at how much better it sounded. You can get more expensive DSP's that are great with some more features and inputs but at this price range this is perfect.

If you're not using this for your subwoofer, you're missing out—100%. Subwoofers are never naturally flat in response, which often leads to a boomy peak between 35-70Hz while completely missing the deep low-end. That’s where the Dayton DSP-408 comes in—it lets you precisely tune your sub for a truly flat response and unlock the deep bass you’re meant to hear. I run a Rockford Fosgate Punch 15" P3 in a small sealed enclosure, which gives me tight, controlled bass but normally rolls off around 37Hz, just as Rockford Fosgate states. My amp has a 30Hz bass boost, which helped extend it slightly, but with the DSP-408, I was able to dial it all the way down to 23Hz—something I never thought I could do in such a compact box. Best part? My wife is happy since I don’t need a massive enclosure to get deep bass. Instead, I just fine-tuned the response with this DSP to get that ultra-low, clean, and powerful bass—without the extra bulk. If you want true control over your sub, this is a must-have. 😎