DiyMobileAudio.com Car Stereo Forum banner

1 - 20 of 98 Posts

·
Moderator
Joined
·
18,547 Posts
Discussion Starter #1 (Edited)
The following is a comparison of the Alpine PXA-H800, Alpine PXA-H701, and Audison Bitone.1 in the technical sense using RightMark Audio Analyzer v5.5.

Below I have tested and compared the analog input stage and optical input stage between the three DSPs.

Note, the test results are only as good as the soundcard I test with. This means the data is limited to what hardware I'm using. Use the data for relative difference research only; do not expect it to match mfg spec and don't expect other's results to be the same. Again, use the data for comparison only. It's good like this. ;)

Furthermore:
DO NOT USE THE DATA TO COMPARE OPTICAL AND ANALOG INPUT STAGES!!!!
Why? Because different soundcards were used to output signal for the optical and analog tests. The same input was used to record, however. More details in the appropriate test section.


The goal of the testing was to compare popular processors against each other using A) the optical input and B) the analog input (RCA; no ai-net).

Note:
All DSPs were powered by an external power supply used to convert 120v AC to 12v DC. This explains the bump in the IMD tests, centered around 60hz.



Let's go...
 

·
Moderator
Joined
·
18,547 Posts
Discussion Starter #2 (Edited)
Testing using the Optical Input:

Hardware Setup:
  • Test signal was generated with RightMark. Signal was 16 bit, 44.1khz.
  • Beach Audio USB Sound Card used to output signal in Digital Format.
  • Toslink cable used from Beach Audio USB Soundcard to the DSP.
  • Analog out from the DSP to Analog In on the M-Audio 2496 Soundcard.
  • All tests resulted in approximately the same input gain level, which is -1.1dB for both Left and Right channels on the M-Audio 2496 Soundcard. The largest delta is 0.3dB on the H701 test.
    This is key because larger swings in test levels can create less truthful comparisons. The goal was also to make sure I stayed within the DSPs nominal range and my previous testing/experience with these units helped me to know where their max was. All data you see is with DSP's outputs unclipped with a 0dB, 1khz tone.
  • Outputs 3 & 4 for used for L/R outputs on ALL DSPs. All settings were FLAT and defeat was used when available to ensure this.
  • Volume was controlled either by DSP software or DSP Controller.
Optical Testing Summary:




Optical Testing Frequency Response:




Optical Testing Cross Talk:




Optical Testing Noise:



Optical Testing Dynamic Range:



Optical Testing IMD:



Optical Testing THD:





Next up, Analog input testing...
 

·
Moderator
Joined
·
18,547 Posts
Discussion Starter #3 (Edited)
Testing using the Analog Input:

Hardware Setup:
  • Test signal was generated with RightMark. Signal was 16 bit, 44.1khz.
  • M-Audio 2496 Sound Card used to output signal in Analog Format via RCAs to DSPs.
  • Analog out from the DSP to Analog In on the M-Audio 2496 Soundcard.
  • All tests resulted in approximately the same input gain level, which is -1.1dB for both Left and Right channels on the M-Audio 2496 Soundcard. The largest delta is 0.3dB on the H701 test.
    This is key because larger swings in test levels can create less truthful comparisons. The goal was also to make sure I stayed within the DSPs nominal range and my previous testing/experience with these units helped me to know where their max was. All data you see is with DSP's outputs unclipped with a 0dB, 1khz tone.
  • Outputs 3 & 4 for used for L/R outputs on ALL DSPs. All settings were FLAT and defeat was used when available to ensure this.
  • Volume was controlled either by DSP software or DSP Controller.
Analog Testing Summary:




Analog Testing Frequency Response:




Analog Testing Cross Talk:




Analog Testing Noise:



Analog Testing Dynamic Range:



Analog Testing IMD:



Analog Testing THD:







- End
 

·
Moderator
Joined
·
18,547 Posts
Discussion Starter #4 (Edited)
Thoughts:
I believe Jim Walter of Alpine said one of their main goals during the design of the H800 was to have a low-noise input stage. Well, it certainly seems they accomplished their goal compared to the 701 and even bitone.

  • The H800 is about 3dB less noisy than the 701 and 6dB less noisy than the bitone. Realistically, though, these values are low already.
  • Intermodulated distortion and THD is lower on the H800 than the other two processors.
  • For analog testing, the FR of the bit1 has a slight bump in the low end while falling between the H800 and H701 in regards to top end FR.
  • For optical testing, the FR is more flat on the H800 than the other two. The bit1 rolls off starting at 6khz and is down 2dB @ 20khz.
  • Optically, the H800 wins out over the other processors again. Lower THD, IMD, Noise, and better FR.
  • You may notice that the Bitone THD & IMD results are odd... really odd. Well, I thought so, too. I re-measured to verify. Same results.
    I went a step further and tested with the input stage set to much lower output. Same result trend.
    I then lowered the output of both L/R channels and lowered the overall volume. Again, same result trend. What you see is what I've verified to be legitimate with my testing. This, again, is why you should use this data for comparative purposes within itself.
    The THD and IMD of the bit1 looks pretty bad. Though, I've personally never had issues with the processor.
    However, if you look only at the summary, the bit1 wins out in THD. All the more reason to use the summary tables AND the graphs together.


If anyone would like me to also test X processor, I'm happy to do it. You'll have to send it to me and cover shipping back (can't do this stuff on my own dime because it's too cost prohibitive). I've saved all settings and can easily replicate them for future testing; that was one requirement in case someone wanted me to compare another processor later down the line.


I'd like to thank Jason (ImJustJason) for donating his H701/C701 combo for testing and Frank for his wisdom on the RightMark software.

I hope you guys enjoy. If you have any questions that I haven't covered here already, feel free to ask. I'll try to answer the best I can.




- Erin
 

·
Premium Member
Joined
·
6,214 Posts
Again, thx Erin...

Seems like Alpine managed to release a top notch product :D Keep up the good work ;)

Seems like the H800 will become the new forum boner seeing how impressive the numbers are. Setting wise it has more stuffs than the BitOne too.

Kelvin
 

·
Registered
Joined
·
26 Posts
I'm particularly impressed by the analog numbers, compared to the other 2 processors. Makes me crave for one.
 

·
Registered
Joined
·
1,090 Posts
How would the AI-net input compare to the analog and digital on either the H701 or H800? Do you think you could do a quick comparo using AI-net between the two?

Thanks for putting in all of this work!
 

·
Registered
Joined
·
3,154 Posts
Hope you can get a comparison to these units and the rockford 363 when it is released as well. I am debating between the two of them (363/h800) at this point. I am excited to see if RF can put up a fight in the processor arena this go around?
 

·
Registered
Joined
·
183 Posts
Thanks bikinpunk. As always, interesting and qualified work.
The IMD is very similar, it’s like more related to the sound card or even software. I didn’t expect that the bitone will be outsider in this company. And interesting, total THD is lower, but due high frequency spectrum.
 

·
Registered
Joined
·
46 Posts
Thanks bikinpunk, for the wonderful work.
 

·
Moderator
Joined
·
18,547 Posts
Discussion Starter #11
How would the AI-net input compare to the analog and digital on either the H701 or H800? Do you think you could do a quick comparo using AI-net between the two?

Thanks for putting in all of this work!
I plan to do this when I put the w505 on the bench (just to check it all works before it goes in the car). I'll try to run the tests comparing RCA in vs. AI-net in and post them up when I can.

I've got to install the H800/w505 today so I can get my car back together. :D
 

·
Registered
Joined
·
8,524 Posts
Erin, I'm looking into the the elevated IMD problem on the digital test. We'll leave the other stuff for another time, the RMAA forum isn't working for me.

What are the setting options for the usb soundcard. Does it have it's own control panel or is it integrated into the windows audio control panel. Is there a internal external sync option. Can you try a record only run at 16/44 while feeding the test signal from a cd player that we know for sure will output a proper S/PDIF CD format?

Set maudio sync to internal when testing the processors from the CD player digi out.

Also, check your windows audio control panel settings. Make sure that they are all where they shold be, ie sample rate conversion to high, HW acceleration high, etc. All those setting deep in the menu. I assume you are using win7 so there could be more options.
 

·
Moderator
Joined
·
18,547 Posts
Discussion Starter #13 (Edited)
XP. I used the same soundcard setup procedure I did for soundeasy, though.

Edit:
that reply sucked.
Let's try again...

I set the both soundcards (usb and m-audio) outputs and inputs to maximum. Everything except playback and record were switched off.
The usb soundcard doesn't have advanced settings unless the software is installed for it. Otherwise it's functions are tied to windows control panel sound settings.
After our previous conversations, I made it a point to stress for people not to compare the optical vs analog results and even more so to only compare results within my same test. I don't trust any 'absolute' measurements. ;)
 

·
Registered
Joined
·
183 Posts
Newermind about this my replica. The all is ok with IMD.
In old times we used the filters for basic frequencies and we had different picture. I newer experimented with measuring the IMD with computer.
 

·
Registered
Joined
·
89 Posts
It would be really cool to compare this from the f#1 status processors.. anyone have one? :)

Sent from my Dell Streak using Tapatalk
 

·
Moderator
Joined
·
18,547 Posts
Discussion Starter #16 (Edited)
How would the AI-net input compare to the analog and digital on either the H701 or H800? Do you think you could do a quick comparo using AI-net between the two?

Thanks for putting in all of this work!
Just tested the H800 from the w505 using all three connections:
  1. Optical
  2. Ai-Net
  3. RCA
Keep in mind these results are given for COMPARATIVE PURPOSE ONLY! Please only look at the data given and compare it within itself. I can't stress this enough.
The purpose of this is to help see what method of input is best and what the tradeoffs are for different input types. Not to define parameters wholly.



Testing the H800's Ai-Net, Optical, and RCA Inputs from the Alpine IVA-W505:

Hardware Setup:
  • Test signal was generated with RightMark. Signal was 16 bit, 44.1khz. Test Signal was burned to CD and played through Alpine IVA-W505 Headunit using the CD source which allows for ai-net and optical output in to the PXA-H800.
  • M-Audio 2496 Sound Card used to output signal in Analog Format via RCAs to DSPs.
  • Analog out from the H800 to Analog In on the M-Audio 2496 Soundcard.
  • All tests resulted in approximately the same input gain level, which is -1.1dB for both Left and Right channels on the M-Audio 2496 Soundcard.
    This is key because larger swings in test levels can create less truthful comparisons. The goal was also to make sure I stayed within the DSPs nominal range and my previous testing/experience with these units helped me to know where their max was. All data you see is with DSP's outputs unclipped with a 0dB, 1khz tone.
  • Outputs 3 & 4 for used for L/R outputs on ALL DSPs. All settings were FLAT and defeat was used when available to ensure this.
  • Volume was controlled either by DSP software.
Input Comparison Testing Summary:



Input Comparison Testing Frequency Response:



Input Comparison Testing Cross Talk:



Input Comparison Testing Noise:



Input Comparison Testing Dynamic Range:



Input Comparison Testing IMD:



Input Comparison Testing THD:







- End


Thoughts:
From the above, it's seemingly obvious that the optical output wins out. It should be the case that both the ai-net and RCA outputs are influenced by the headunit DAC and, if that is indeed the case, then it's also obvious that the RCA output is the worst way to go out of this deck, assuming you have the ai-net as an option.

The problem, then, is you're limited to the headunit's DAC.
Now, some decks may test better. The downside there is you won't have the luxury of the ai-net control. This is a tradeoff. For analog, you may not need the ai-net control; it's really only primarily useful for things such as preset and subwoofer level control for the H800. If that's the case and your deck has a good DAC built in, then you're probably just fine.

Also keep in mind one downfall of this testing is that the output of the headunit from the RCAs needs to be verified as being unclipped. If I were to toss another random deck in, drive voltage up to meet required test threshold, there's a good possibility that the outputs could be clipping and murdering the results. Luckily, I've owned this deck before and know it's limits because I've tested it (a few times).
If I were starting with a new deck, I'd test the output at intended test deck volume to make sure it wasn't driven to clipping. Luckily, though, this is really a non-issue; every deck I've tested thus far didn't clip at max volume using a 0db, 1khz track. Can't guarantee they won't all do this, though...

However, since this is the gear I'll be using in my car for the time being, the obvious choice is to go with an optical output and ai-net output rather than RCA output.
 

·
Registered
Joined
·
193 Posts
Erin, about a year ago you wrote a wonderful, and glowing, review of the MS-8. If not to be included in your test, here, would love to at least hear your impressions of how all of these processors stack up against the MS-8 once you've had enough time with the H800. Thanks for all you are doing for the car audio community....
 

·
Moderator
Joined
·
18,547 Posts
Discussion Starter #18 (Edited)
That's the plan. I just gotta get it installed first. I'm testing everything right now because the testing won't be easy to do once it's installed in the car.


For anyone who is wondering...
The w505 + h800 combo does not clip with the settings set to flat on the H800 using channels 3 & 4 outputs.
Test: 1khz, 0dB using my oscilloscope.

The w505 clips @ volume level 25 with a 1khz, 0dB tone.
 

·
Moderator
Joined
·
18,547 Posts
Discussion Starter #19
60hz is from the PSU. I noted that at the beginning.

No large external battery to bring upstairs.

I've always been told that ai-net is analog and controlled digital volume. Digital is digital, though.
Seems to be the case, too, when you remove analog (ai-net or RCA) you no longer get FM/iPod/etc. If the digital is connected you get CD but that's it.
 

·
Registered
Joined
·
1,310 Posts
Erin-

Thank you for taking the time to do the comparison. It certainly helps everyone else that you write good product reviews and are a fan of trying new stuff out (to put it mildly). :D I don't have any plans to change out my setup, but my wife wants something better in her Murano and I'm leaning heavily towards one of these units that has some of the Auto-EQ built in. At this point I'm between the H800 and the MS8...so I too am eagerly awaiting your product usage review...oh, and I hope you like it as well (un-selfish moment).
 
1 - 20 of 98 Posts
Top