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Thread: Discrete Vs. Integrated YM3438: Sega Genesis music blind test results.

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    Master of Shinobi MaxWar's Avatar
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    Default Discrete Vs. Integrated YM3438: Sega Genesis music blind test results.

    Alright folks, the time has come to reveal the data acquired from the audio blind test experiment that was started a week ago.

    As the title implies, the subject of this study was:

    Discrete Vs. Integrated YM3438.


    The goal was to evaluate if these two chips sound significantly different from each other and if so, which one was preferred.
    I wrote a load of details and explanations so most questions you might have about the test are likely explained down there.
    I also added lots of pictures so hopefully its a good read and you do not get that TL;DR feeling. But if you still do, you can skip right to the results and conclusion, I guess...

    Background Information:


    On the original Sega genesis model 1, the FM audio chip is the Yamaha YM2612. This is a digital FM synthesizer with an integrated DAC ( digital to analog converter). This DAC was the main flaw of this chip as it introduced a lot of noisy artifacts during the conversion.



    Yamaha then developed the YM3438, which is basically a CMOS version of the YM2612 but they also improved the DAC. This new DAC greatly reduced the amount of processing noise/aliasing in the sound.



    The stand alone YM3438 chip ( or discrete ) seen above was never used in a Sega genesis console however. Instead Sega integrated the new YM3438 FM synthesizer inside a large general purpose ASIC, the FC1004. This chip was used in the model 1 VA7 and model 2 VA0, VA1 and VA1.8 revisions of the genesis console.


    Now the interesting part is that supposedly, the DAC was even further improved in this model and it removed the Bit depth truncation associated with the Ym2612 and Ym3438. You can read about this on wikipedia. So basically this would mean that the Sega Integrated YM3438 (FC1004) is the best version of the 3438 ever made. At least according to the literature.


    The Crystal Clear audio mod. (CCAM)


    Ok So basically the best version of the FM chip is inside the early model 2 consoles, which ironically are renowned for having the worse sound!
    The horrible quality of the sound however has nothing to do with the chip but rather with the lackluster amplification circuit Sega used in those consoles.
    This is what Tiido Priimägi wanted to fix when he started developing the Crystal clear audio mod years ago. I am sure most of you have at least heard about this mod. It is a pretty complex mod so only few people as of now benefit from it. Basically it takes your crappy early model 2 and turns it into the best sounding Sega Genesis possible. But you need to build this circuit first.


    The important detail is that this circuit only works with the YM3438 ( ASIC YM2612 as Tiido put it back then), and not the discrete YM2612 of the model 1. The reason for this is that they have different type of outputs ( YM3438 is louder ). As a result this circuit was only to be used on model 2 consoles and did not work on model 1 consoles ( except VA7, which is basically a Model 2 in model 1 case ). This was not considered a major problem because the model 1 already had a decent amplification circuit. However those looking for the ultimate audio for the genesis would get a model 2 and a CCAM as this setup is much better than a stock model 1.

    As of now there are no CCAM equivalent for the Model 1. While the amp in the model 1 is already pretty good, the main reason to this is that the YM2612 was considered inferior so most modders did not consider it worth the bother to develop a better amp for it.


    Now what if we swap the YM2612 in the Model1 for a YM3438?


    The two chips are pin compatible so in theory it is pretty simple to remove the YM2612 in a model 1 and install a YM3438 instead. But remember that the two versions of the chip output differently so If you simply swap them over your genesis 1 will output garbage as sound. The genesis 1 onboard amp is inadequate for the 3438.

    AFAIK this problem had not really been assessed and documented until earlier this year when a few modders, EvilDragon and Drakon among possibly others got in their mind to make this work. This concluded with a YM3438 working in a genesis 1 using a modified model 1 amplifier.

    While this experiment was successful in the end it mostly went under the radar and was seen as a curiosity rather than something actually useful. One of the main reason for this is that it was assumed that the Discrete YM3438 was significantly inferior to the YM3438 that is integrated in the model 2 genesis. In other words the the stand-alone discrete YM3438 was seen as pretty much an equivalent of the YM2612 while the true superior chip was the FC1004 found in the model 2.

    This is where I came in and repeated that experiment myself. However instead of using a modified model 1 amplifier on the discrete YM3438 I used the CCAM amp. It immediately struck me that the discrete YM3438 was being underrated and in fact was much more similar to the integrated YM3438 than was popularly admitted.

    I also knew that simply saying so would be seen as: "well, thats just your opinion" and that this would be lost in the immensity of the internet all the while people would continue to occasionally speculate about it.

    So i went a bit nut and decided to make this a big deal and do this blind test experiment to once and for all go to the bottom of the question and substitute all the talk by actual facts!

    The blind test and comparative recording methodology.


    I do have some experience in comparative recording methodology. Actually, as far as i know, no one in the retro gaming/modding scene went as far as I did in perfectionism regarding to this. What I am doing is more akin to what is found in the professional audio industry and among hardcore audiophiles rather than the retrogaming circles.

    I wrote a precise protocol for this, which I used before for comparing different sound cards, different Famicoms and even the impact of recapping systems on sound quality. Most of this protocol can be found here. I will answers questions about it if need be.

    To sum it up the basic idea of the comparative recording recording methodology is to limit all external sources of variation as much as possible and leave what you want to compare as the only significant source of variation. Its pretty straightforward really.


    Details on the hardware setups I used.


    For this blind test experiment I had two consoles.

    The first one is a standard Genesis model 2 VA1 with CCAM amplifer.
    The second one is a Model 1 VA3 with its YM2612 chip replaced by a YM3438 and also uses the CCAM amplifier.

    Both are recorded into audacity using the exact same presets and recording hardware and I used the very same CCAM circuit on both machines.
    My CCAM circuit was made by RetroGamer343 from Sega16 and I modified it to have very little LowPass filtering, according to the original Tiido schematics.

    Typically a CCAM amp is permanently installed into a console. However I wanted to use the very same circuit on several consoles so I made a modular setup.
    Here you can see I mounted the CCAM PCB inside of a grounded tuna can which serves as a complete RF shield for the circuit. I installed RCA connectors on it, one side connects directly to the chip and the other side connects to the recording device.



    On the consoles side, all preparation was made in a consistent manner. The chip outputs were completely isolated from the motherboard either by cutting traces or removing components. The chip output was then connected directly to the CCAM and nothing else via fully grounded shielded cables.

    Here is a close view of the connections on the Model 2 VA1.


    Here you can see that the YM3438 in my model 1 is installed in a socket and similarly connected with shielded cables. The PSG here is tapped on the underside of the board, unseen in this picture.


    Here is a view of the complete model 1 setup just prior to recording.


    Blind test results:


    First I will declare that these results are real and I did not falsify or modify any of the numbers. These are exactly what I received from the participants. While I think it is better to keep the choices and identity of indivitual participants anonymous, I still stand behind this data and rest my reputation and credibility on it as I know this is 100% genuine. If need be all the PMs I received could be verified by a third party and the data double checked. Furthermore, I encourage participants to discuss their experience in the thread now that the results are in.
    -----------------------------------

    In total 30 people from across 5 forums participated in this blind test spanning a period of 1 week.
    This is slightly more than I was initially hoping for so I am happy with this number.

    As you now know the two console were a Genesis 2 VA1 with CCAM and a GENESIS 1 with discrete YM3438 + CCAM.

    The Model 2 VA1 recordings were respectively:

    CONTRA-A
    D&D-B
    SONIC-A
    ThunderForce-B
    Turrican-B
    By logical opposition the YM3438 Modified model 1 were

    CONTRA-B
    D&D-A
    SONIC-B
    ThunderForce-A
    Turrican-A
    So for those who made the test, I guess you can now compare with your results and see where you are at


    The rundown:

    As i said, a total of 30 people made the test.

    -8 out of 30 people said they could not make any difference at all and responded "no opinion" for all the music pairs.

    -7 out of 30 people gave a clear response for all the pairs.

    -15 out 30 people responded "no opinion" for at least one or more of the pairs.


    Contra results.

    -10 out of 30 people had an no opinion on this one.
    -12 out of 30 preferred the Integrated YM3438 version (Contra-A)
    -8 out of 30 preferred the Stand-alone YM3438 version (Contra-B)

    Dungeon&Dragons results:


    -14 out of 30 people had no opinion on this one
    -4 out of 30 preferred the Integrated YM3438 version (D&D-B)
    -12 out of 30 preferred the Stand-alone YM3438 version (D&D-A)

    Sonic 2 results:


    -15 out of 30 people had no opinion on this one
    -3 out of 30 preferred the Integrated YM3438 version (Sonic-A)
    -12 out of 30 preferred the Stand-alone YM3438 version (Sonic-B)

    ThunderForce IV results

    -13 out of 30 people had no opinion on this one
    -8 out of 30 preferred the Integrated YM3438 version (ThunderForce-B)
    -9 out of 30 preferred the Stand-alone YM3438 version (ThunderForce-A)

    Mega - Turrican results:


    -12 out of 30 people had no opinion on this one
    -8 out of 30 preferred the Integrated YM3438 version (Turrican-B)
    -10 out of 30 preferred the Stand-alone YM3438 version (Turrican-A)

    Mean total results:

    Each participant evaluated 5 samples and we had 30 participants so that makes a total of 150 samples.

    -64 out of 150 samples received a "no opinon" verdict.

    -35 out of 150 samples favored the model 2 with Integrated YM3438

    -51 out of 150 samples favored the model 1 with Discrete YM3438





    Conclusion:


    It was observed through this test that when people were asked to blindly chose between the two choices, they would not find any detectable differences 42% of the times. By opposition when they did make a choice between one or the other, they were just as likely to prefer one or the other. I therefore conclude that for the average user, there would be no significant perceptible difference in using one chip or the other. This can be concluded with an acceptable degree of certitude considering the size of the sampling pool and the distribution of the data.

    The practical conclusion of this is that we can assume that the highest sound quality on a genesis is also achievable on a Model 1 machine and not only on the model 2. High quality CCAM audio is no longer something that should be associated strictly with a Model 2. The stand-alone YM3438 chip is just as capable of delivering quality sound as the integrated one.

    Possible Caveats



    Now this test was limited to a subjective appreciation of musical samples. There are other potential aspects that could complicate the application of the results.

    - Wild discrete YM3438 chips not being all created equal: The only way to get these chips in the wild is mostly by ordering them from Chinese part distributors. There is always a possibility of bad batches or bootleg chips being in circulation. I made this test using 1 single chip that I evaluated was a good genuine specimen. While it seems that in my case it turned out very well, there is no data on the reliability of finding these chips in the wild.

    -Compatibility issues: My personal experience with the discrete YM3438 was of 100% compatibility in all the games I tried, but this is no more than a dozen games. There are reports of timing incompatibility issues in other games using this chip.
    So far issues have been reported in:
    -Sonic Spinball.
    -Earth worm jim.
    -Super fantasy zone.

    I am now awaiting to receive a copy of Sonic Spinball to test this myself. I will update this page with my findings.
    The good news is that it is possibly a fixable issue but that would make the implantation of the genesis 1 modification even more complicated than it already is.

    A few last words

    Firstly, once more, thank you to all who contributed with their inputs

    In the end it is less complicated to use a CCAM on a model 2, but the adventurous modder who prefers model 1 for whatever reason now has an option to get that nice CCAM sound on a model 1, with no compromise on the sound quality.

    Personally I prefer using a discrete YM3438 on a model 1 if only because there are interferences issues on the FC1004 based model 2. This will produce a characteristic buzzing noise that modulates along the activity of the console. This can be heard as a buzz in the beginning of the D&D song included in this test package. A handful of people made mention of it but no more. This is a consequence of the Model 2 ASIC/board layout and the discrete implementation on a model 1 does not suffer from this.

    HOWEVER, there is a later version of the Genesis Asic, also known as the GOAC ( genesis on a chip ) which basically integrates everything on the console in a single chip. The integrated 3438 on these does not suffer from noise issues. In fact they have the cleanest output of all the genesis consoles. These can be found exclusively on Model 2 VA4 and Genesis model 3 consoles.
    They however have an altered/wrong sound balance between FM and PSG so implementing the CCAM on those requires a little fix.


    Edit: Also, sorry in advance if I forgot to mention a relevant link or to name a relevant person in the post. I will add details, references, links and answer questions on request.
    Last edited by MaxWar; 08-03-2013 at 10:00 PM.

  2. #2
    Mastering your Systems Shining Hero TmEE's Avatar
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    Ah damn, I was too late to the party :P I downloaded the files and listened some and I could clearly hear some were more muffled than others, and I can see why. The can you made is neat but you need those longass cables to connect it to the YMs... however due to the characteristics of the YM output you'll have some problems with long cables (shielded or not) and higher end of the freq spectrum...
    Technically there cannot be any kind of difference in actual sound generation in the chips, or there would be a lot of games that sound flat out wrong (early emulation kind of wrong), besides the number of bits the DAC will see, but that only affects pretty small part of overall sound (quantization noise, and the extra distortion form YM2612 DAC bug which I emulate in my FM core too).
    The buzzing noise is caused by VDP and unfortunately it cannot be rid from the sound, the VDP and YM are on same physical chip and crosstalk happens nicer in microsocopic scale. This is actually the main reason I started looking at YM3438 in the first place but then I discovered something nicer that is possible to do :3
    Death To MP3, :3
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    Master of Shinobi MaxWar's Avatar
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    Quote Originally Posted by TmEE View Post
    Ah damn, I was too late to the party :P
    Sure would have been nice having you participate in the test

    Quote Originally Posted by TmEE View Post
    The can you made is neat but you need those longass cables to connect it to the YMs... however due to the characteristics of the YM output you'll have some problems with long cables (shielded or not) and higher end of the freq spectrum...
    I knew beforehand that this was not 100% ideal in this regard but I made this test on 5 different consoles, not just the 2 showcased here in this test.
    I also made it On model 1 VA7 , Model 2 VA3 and Model 2 VA4. So i really benefited from the modular setup, having to custom install the CCAM in every console with minimal wire length would have been a HUGE hassle. However I used similar lenght and type of wire in each console, so whatever minimal effect this might have one the sound should be consistant in all consoles.
    I hence dare claim it is not of significant importance for the purpose of this blind test. But you can be sure when I make a permanent CCAM install I will try to make wires short.

    Quote Originally Posted by TmEE View Post
    The buzzing noise is caused by VDP and unfortunately it cannot be rid from the sound, the VDP and YM are on same physical chip and crosstalk happens nicer in microsocopic scale. This is actually the main reason I started looking at YM3438 in the first place but then I discovered something nicer that is possible to do :3
    Haha, I hear ya! Thats too funny xD
    I initially tried the CCAM in a VA7 and got annoyed at the VDP noise. This is what prompted me to test the amp in so many different consoles and then go for the discrete version of the chip and check that out too

  4. #4
    YM3438 Master! ESWAT Veteran evildragon's Avatar
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    Gah I forgot about listening to those..

    Oh well. I do indeed like the results however. It was a blind test, and the results speak for themselves.
    Customized Sega Genesis Model 1 - VA3. Energy efficient with buck converters instead of LM7805's.


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    Sega Nerd WCPO Agent oldskool's Avatar
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    I was going to download them myself but got side tracked and now it's ended. The results and test are somewhat what I had in mind. Being that for the average user - whatever you were comparing - there would be no noticeable difference. Interesting!
    MY SEGAS
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    I remain nonsequitur Shining Hero sheath's Avatar
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    Interesting study. I wonder how the X'Eye or Model 1 HDG would sound without modification to the average listener.
    "... If Sony reduced the price of the Playstation, Sega would have to follow suit in order to stay competitive, but Saturn's high manufacturing cost would then translate into huge losses for the company." p170 Revolutionaries at Sony.

    "We ... put Sega out of the hardware business ..." Peter Dille senior vice president of marketing at Sony Computer Entertainment

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    Sega Nerd WCPO Agent oldskool's Avatar
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    I have heard people say that JVC had the best sound hardware. I remember my X'Eyes and I do recall that they sounded very well.

    Is there any truth to these claims?
    MY SEGAS
    [Model 1 Sega CD x 5] [Model 1 HD Genesis w/Component Video] [Model 2 Genesis] [32X CIB] [Master System Model 3010] [Nomad w/LCD mod] [Dreamcast] [Saturn] [Game Gear]

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    I remain nonsequitur Shining Hero sheath's Avatar
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    I think my Genesis 1 HDGs sound better for FM+PSG, especially for bass and higher pitches, I think my X'Eye sounds better for samples and CD-Audio but only slightly. I think it just sounds a bit cleaner and I'm not sure if that isn't just because it isn't coming out of a headphone jack, passed through the Sega CD and then output through Composite Audio cables.
    "... If Sony reduced the price of the Playstation, Sega would have to follow suit in order to stay competitive, but Saturn's high manufacturing cost would then translate into huge losses for the company." p170 Revolutionaries at Sony.

    "We ... put Sega out of the hardware business ..." Peter Dille senior vice president of marketing at Sony Computer Entertainment

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    Master of Shinobi MaxWar's Avatar
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    The X'eye uses the 315-5660 ASIC . Exactly the same one as the Model 2 VA0,VA1,VA1.8 and VA3. (The model 1 VA7 uses the 315-5487)

    Since it uses the same asic, it would sound just like an early model 2 with a CCAM.
    However I do not know what stock sound circuit looks like but I bet its much better than the crap used on Sega early model 2

    About stock model 1, I have recordings of the very same songs used on the blind test. I recorded them on a freshly recapped HDG model 1 VA3, using the same exact recording methodology and preset as for the blind test.

    Im having sync issues with my google drive right now but will link em here as soon as its sorted.

  10. #10
    Master of Shinobi MaxWar's Avatar
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    Ok because you guys obviously LOVE audio comparisons, I have some more quality data for you.

    Stock Sega Genesis Model 1 recordings

    Firstly, many of you expressed the wish to have recordings of the Original Stock Model 1 High definition graphic Sega Genesis to compare with the CCAM recordings in the blind test.

    So here it is, minus Turrican Intro, which I do not have.
    Those have been recorded using the same exact methodology used for the blind test.
    Contra and D&D are from a VA6.
    Sonic 2 and ThunderForce are from a VA3 and the console was connected to a CRT because it is an older recording I made.
    For a while now I have stopped making recordings of consoles when connected to a CRT tv. I now know this will induce a low volume high pitch feedback in the sound.
    The effect is relatively minor though. See if you can detect it in the sound

    DnD-Valley1-M1VA6.flac
    TFIV-levela1-VA3(postrecap).flac
    CHC-Gamestart-M1VA6.flac
    Sonic2-Emerald1-VA3(postrecap).flac

    *I will let you guys discuss observations you make before commenting on my own

    *More of my recordings can be found here : http://www.sega-16.com/forum/showthr...943#post591943

    Comparative Study of the Background noise in different YM3438 equipped Sega Genesis consoles.


    In this test we have 4 consoles, which are representative of most YM3438 setups.

    -Model 1 VA7 : FC1004 Asic model 315-5487 ( Afaik this Asic is exclusive to the VA7)
    -Model 2 VA1 : FC1004 Asic model 315-5660 ( Asic also found in M2Va0,Va1,Va1.8,Va3 and X'eye)
    -Model 1 VA3 : Equipped with discrete YM3438 ( same machine used in the blind test )
    -Model 2 VA4 : FJ3002 Asic model 315-5960 (M2Va4, M3Va1)

    Please download this file containing a short sample of background noise for each of these. Total download is about 2mb
    https://docs.google.com/uc?export=do...EwyRElFVU1wX3M

    These samples are all of the same exact snippet of the Mega Turrican Intro. I left parts with actual sound so you can estimate how loud is the noise compared to the audio. Sound levels are normalized so the audio level is consistent from one sample to the next.
    Mega turrican is quite representative of your average Megadrive game regarding sound level. Some games are louder, some are quieter. Naturally, the quieter the actual audio is, the more the noise will contrast.

    Those are all recorded with the same CCAM PCB. However please note that they were all recorded with the Stock RetroGamer CCAM amp, which comes with a lowpass filter ( 0.28uF ceramic caps to ground ) to make it sound closer to a Stock Model 1. I do not have all these samples recorded with the unfiltered CCAM used in the blind test sadly. However this should do perfectly well to compare the relative magnitude of the signal to noise ratio across those different consoles.

    As far as i know I am missing at least the following 2 ASIC YM3438 but I do not have any machines containing them so I cannot test.

    -FF1004 Asic model 315-5700 : Possibly the rarest ASIC, Found in the Sega Nomad and in some model2 VA3
    -FQ8007 : found in the late Genesis model 3 (M3Va2)

    Now lets look at the waveforms



    I am sure you can tell the difference simply by listening to the samples, but its cool to also check the waveforms.

    These are the very waveforms of the Flac samples for download in this thread.
    For each file there is a full view of the waveform in stereo as well as a super zoom of the Left channel.
    In each case the Super zoom consists of 500ms of audio from the same region between 2.5-3s of the audio file.
    The vertical scale is also the same. Maximum displayed amplitude is 1 db in normal view and 0.1 db in super zoom.

    I took a measure to partly fool proof these results and made recordings of a Model 2 VA3, which also uses the 315-5660 and the SNR is consistant with the M2VA1.

    Model 1 VA7 : FC1004 Asic model 315-5487




    Model 2 VA1 : FC1004 Asic model 315-5660




    Model 1 VA3 : Equipped with discrete YM3438




    Model 2 VA4 : FJ3002 Asic model 315-5960




    60hz multiples ?

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    I remain nonsequitur Shining Hero sheath's Avatar
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    I've been listening to everything posted here repeatedly since yesterday on my PC speakers with subwoofer, standard Logitech setup. I couldn't see what was playing and I wasn't actively trying to peg whether it was a CCAM or apparently recapped VA6 or VA3. This morning I started looking occasionally at the file playing as the files repeated and I could never guess except with the one Sonic 2 VA6 file because it was a little filtered (non-CCAM).
    "... If Sony reduced the price of the Playstation, Sega would have to follow suit in order to stay competitive, but Saturn's high manufacturing cost would then translate into huge losses for the company." p170 Revolutionaries at Sony.

    "We ... put Sega out of the hardware business ..." Peter Dille senior vice president of marketing at Sony Computer Entertainment

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    Mastering your Systems Shining Hero TmEE's Avatar
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    Have decibel scale on the waveform graphs, the normalized scale has no real reference to anything so it makes things harder to judge.

    Most of the noise can be vastly minimized with couple of carefully placed capacitors on power rails.
    Death To MP3, :3
    Mida sa loed ? Nagunii aru ei saa "Gnirts test is a shit" New and growing website of total jawusumness !
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  13. #13
    Master of Shinobi MaxWar's Avatar
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    Quote Originally Posted by sheath View Post
    I've been listening to everything posted here repeatedly since yesterday on my PC speakers with subwoofer, standard Logitech setup. I couldn't see what was playing and I wasn't actively trying to peg whether it was a CCAM or apparently recapped VA6 or VA3. This morning I started looking occasionally at the file playing as the files repeated and I could never guess except with the one Sonic 2 VA6 file because it was a little filtered (non-CCAM).
    You mean you have a hard time telling appart CCAM with HDG model 1 samples? Did you use the CCAM samples from the blind test or the CCAM samples from the my genesis sample thread? Because the ones on the genesis sample thread are from the filtered CCAM, which sounds much more alike to a HDG mode 1 than the "unfiltered" CCAM samples in the blind test.

    I have not yet added the "unfiltered" samples to my sample thread.

    Quote Originally Posted by TmEE View Post
    Have decibel scale on the waveform graphs, the normalized scale has no real reference to anything so it makes things harder to judge.
    The DB scale is there on the left of each graphs.

    Quote Originally Posted by TmEE View Post
    Most of the noise can be vastly minimized with couple of carefully placed capacitors on power rails.
    That would be an interesting thing to try. Although this VDP buzzing noise comes and goes with what the machine is doing, it seems related to the 60hz of the power line.

  14. #14
    Mastering your Systems Shining Hero TmEE's Avatar
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    db don't range from 0 to 1, but infinity to 0, where 0 is loudest.

    Half the buzzing comes from power rails themselves. Hook up a scope to some and look how much ripple there is.
    Death To MP3, :3
    Mida sa loed ? Nagunii aru ei saa "Gnirts test is a shit" New and growing website of total jawusumness !
    If any of my images in my posts no longer work you can find them in "FileDen Dump" on my site ^

  15. #15
    I remain nonsequitur Shining Hero sheath's Avatar
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    Quote Originally Posted by MaxWar View Post
    You mean you have a hard time telling appart CCAM with HDG model 1 samples? Did you use the CCAM samples from the blind test or the CCAM samples from the my genesis sample thread? Because the ones on the genesis sample thread are from the filtered CCAM, which sounds much more alike to a HDG mode 1 than the "unfiltered" CCAM samples in the blind test.

    I have not yet added the "unfiltered" samples to my sample thread.
    I just added the CHC and D&D VA6 and TFIV and Sonic 2 VA3 files you posted above to the blind test files from before and cycled them through on the same playlist. With headphones I have to be paying attention to notice, with my PC speakers plus sub I only occasionally notice one being a little more filtered, I think it is the Sonic 2 VA3 one.
    "... If Sony reduced the price of the Playstation, Sega would have to follow suit in order to stay competitive, but Saturn's high manufacturing cost would then translate into huge losses for the company." p170 Revolutionaries at Sony.

    "We ... put Sega out of the hardware business ..." Peter Dille senior vice president of marketing at Sony Computer Entertainment

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