Dayton Audio DSP408 /miniDSP 6x8

I would think if it only handles 3.2v for input, then you might get some clipping over that.

Maybe disconnect rca inputs, and connect voltmeter to one. Play the 0db test track and measure the voltage at the rca. Turn up the radio till it hits 3.2v. then you know where your limit is for the DSP input.

 

Nothing worked. Nothing got rid of the noise. Called Parts Express and they said I'll need filters because the kenwood puts out more volts at the outputs than the max allowed volts at the dsp input.

I shouldn't have to buy more shit to make something work correctly. So I sent it back to Amazon and am looking for something else

 

I picked up one of these units this summer myself. This is disconcerting news since my Pioneer has 4W of output voltage. Might be best to do something else as well.

 

I'll be honest, I think it was 100% my fault - I don't think I had my order of operations correct at all. I'm doing that now. I think what I did wrong was a stupid error.

I had all the inputs turned to 100. I shouldn't have done that. I should have set them each individually (with the other channels muted in the software) while having it connected to the DD1.

Stupid error, but I was so frustrated last night, I just packed it up, clicked return in Amazon, and dropped it off at the Amazon return kiosk at Kohls.

Last night, after all was said and done, I found a page dedicated to the DSP408 on Facebook that I wish I had found earlier.......

Anyway. I ordered a miniDSP C-DSP 6x8. While I'm waiting for it to come in, I'm going to take the opportunity to re-organize the back of the rack wire routing-wise. I'm also going to replace the Stinger 4000 RCA cables with better shielded coaxial RCA cables.

 

Oh yeah, you should have adjusted the 408 inputs.

Look at knukoncepts RCAs. That is what I will be running.

 

Hahahahaha right? Oh well. The miniDSP is in the REW as a default dsp, so there is good integration there.

 

I’ve been waiting for this. Nowhere on the planet have I seen any credible audio guy laud the quality of the Dayton DSP.

I like the JL or Audio Control personally. Good luck with the MiniDSP. I don’t know anything about it.

 

Honestly, it wasn't ideal lol

 

How much was the miniDSP?

 

275.

 

Agree with @dolbytone. I can tell you that you will NOT be disappointed with JL Audio’s TWK-88. It’s a fantastic DSP.

Cheers

Rick

 

Well the miniDSP came in today. No annoying whining noise. All the games and levels have been set correctly. I haven't even gotten to eq-ing each of the channels and it already sounds great.



Initial throw together crossovers-

Widebands - 1200hz - 20000hz 24dB slope
Woofers - 90hz - 1200hz 24dB slope
Subwoofer - 20hz - 90hz 24dB slope

This is the initial tune, just to get me rolling. I'm going to be using Andy's tuning guide and Room EQ to.eq the channels.

 

As a side bar, setting gains was a bit of a process. I used a process from the miniDSP web forum, but tailored it to my needs:

1. 1. Be sure that all EQ, crossovers, time alignment and any other sound adjustment software in both the head unit and DSP software are set to "off" or 0. Could take a while to find everything and turn it off. Don't forget sound effects as well.
   
2. Mute all of the outputs on the DSP first and hook your oscilloscope to an RCA output from the head unit. I just unplugged the RCA line at the DSP input and plugged my O-scope into that (Easier than taking the head unit out). I used a
   $198 SMD DD1 SMD Distortion Detector DD-1
   SMD DD1 rather than an actual O-scope.
   
   
3. Play a sine wave and put it on repeat so you can work freely. I personally used a 1khz recorded at 0dB for the front channels and 40hz at 0dB.
   
   
4. Turn the volume knob up slowly until the sine wave starts to distort or gets flat lines on top and bottom. The wave can distort in different ways from my experience. It can get oddly shaped. You'll know just looking at it when it gets squirrely. Back it off a little until the wave gets clean.
   
   a. Note, don't be surprised if you can go all the way up without clipping. I was able to and I've read that it's quite common these days for HU's to put out a clean signal at Max volume. The Kenwood DMX905s will go all the way to the top end (40) with the 1khz tone, but only 30 with the 40hz tone. I ended up setting my max volume as 35 for the front stage and 30 for the sub.
   
   
5. Leave the volume at that level. That's the max your HU can go before clipping.
   
   
6. My next step was to set the input gains on the DSP. Something I learned doing this was that you're more than likely going to set either the input gains or output gains. You'll leave one or the other at 0 across the board. So I pulled an RCA output from the DSP and only unmuted the channel I was setting. Plugged my O-scope into that channel making sure head unit volume was all the way up.
   
   a. Played the same sine wave for output channels 1/2/3/4 (1khz, 0dB individually) and slowly turned up the output slider in the DSP software. The wave started to distort around (for channel 1/2/3/4) 5.3. So I backed it off to 5.0. I just set all output gains for channels 1/2/3/4 to 5.0 to make it easy. I left the DSP input gains all at 0.
   
   b. Played the same sine wave for output channels 7/8 (40hz, 0dB individually) and slowly turned up the output slider in the DSP software. The wave started to distort around (for channel 7/8) 1.3. So I backed it off to 1.2. I just set all output gains for channels 7/8 to 1.2 to make it easy. I left the DSP input gains all at 0.
   
   
7. Now it's time to set gains on the amp. With all the speaker wires unplugged, I muted all channels except the one I was setting. I did these each one at a time. Because my amp has it's own clipping alert feature (MILC), I was able to set channels 3/4/5/6 on the amp using that feature. For channels 1/2 (tweeters) I set the gains using a digital multi-meter using audio-math to match the gains to the max RMS of the tweeters - 40W rms @ 4ohms = 12.6491v. I rounded up to 12.7v

 

How does it sound?

Sounds like maybe you had a bad Dayton unit.

 

I sounds like it needs some tweaking, but it sounds nice. When the sub gets here it will sound much better honestly. It definitely sounds nicer than it did with the passive crossovers. The widebands on the dash sound crisper.

 

Holy crap. Time alignment!!!!

I used this calculator

https://www.erinsaudiocorner.com/timedelaycalc/

Set it up, and boom!

Sub came in too.

 

Night and day, eh?

Gotta love some Erin's - he's been testing a ton of stuff lately.

Is that a Speakon connector on your sub box?

 

Yes/no. It's a speakon connection but my wiring. Bad position though lol.

 

After a couple of weeks, I've decided to go back to the Morel Tempo Ultra tweeters instead of the CCWR 254 widebands. I was missing just a little bit of detail at the top. I have them crossed over at 1800 24dB slope with the 6x9 drivers topping out at 1800 24dB slope. The detail at the top is a lot nicer. The passive crossovers that came with the set crossed at 3200 6dB.


I still haven't gotten the opportunity to get rolling with the REW to EQ each of the channels - it just seems like there isn't the time to dedicate to it right now. That said, I used Erin's time alignment calculator and set up 3 listening positions, and they sound great!