I am using a brand new Mac Mini (4GB RAM running OS 10.6.5) to run primarily FLAC audio tracks to my stereo system’s preamp, a McIntosh MX132 via the TOSLINK digital audio out.
The problem is that at the end of every song, it seems like the Mac Mini stops sending the audio signal to the preamp during the “gap” between songs, as evidenced by the L/R audio input indicator lights on the front of the preamp going out. When the next song starts, it takes about 1-2 seconds to re-establish the connection (i.e., for the indicator lights come back on on the preamp) and so I don’t hear the first second or so of that next song.
This problem happens with both FLAC and ALAC files using Songbird and iTunes. It also happened when I used the VLC player software.
I am using two other TOSLINK audio inputs from my DVD player and Cable TV box, both with no problems.
I have changed out the TOSLINK cables and switched the Mac audio output into the other 2 preamp TOSLINK inputs with no success.
Also, I tried a 3.5mm-to-dual RCA splitter and ran the analog audio out from the Mac Mini's headphone jack and it works fine. So the issue is only with the TOSLINK digital/optical output.
I have tried different software audio players (iTunes, Songbird, VLC) and this happens with all 3. I have also tried both ALAC and FLAC files, which play fine on another computer (i.e., the song files definitely are OK).
I have also tried “gapless” playback and this does not solve the problem.
I've researched this online and can't find anyone with a similar problem. I'm hoping it's just something simple I'm overlooking. I have tried playing with the gapless and crossfade settings in iTunes but I think the issue is either with the audio out from the Mac Mini or how the preamp is handling the audio input via Toslink.
Any help would be greatly appreciated. Thanks.
Paul
Sounds like an issue with they way you amp deals with digital signal. I use 3.5mm-to-dual RCA splitter so i hooked up my MacMini to my amp via Toslink and can't recreate this issue with my MacMini, is it possible for you to try another Amp ? It could very well be the amp causing the problem.
Also try going to audio midi set up in the utlitiles folder and make sure the digitial output is set to 44100.hz and 2ch 24bit.
Do you have the same output sample rate set as the tracks are?
Thanks for the help, I have a few more questions as I try to solve this problem.
Sounds like an issue with they way you amp deals with digital signal. I use 3.5mm-to-dual RCA splitter so i hooked up my MacMini to my amp via Toslink and can't recreate this issue with my MacMini, is it possible for you to try another Amp ? It could very well be the amp causing the problem.
I think it's at least partly the amp, it seems like it's slow to reconnect/sync with the audio output.
Question: why do you use the analog audio output which is coming from the Mini's amplifier which I'm assuming is not very good? I haven't done that (except to test) because I assumed the audio quality was low. One solution I'm considering is to take the digital audio output and run it thru an external DAC (something like this: http://www.hirestech.com/products/) (http://www.hirestech.com/products/)), which then provides an analog output that my preamp should be able use without the digital switching problem.
Also try going to audio midi set up in the utlitiles folder and make sure the digitial output is set to 44100.hz and 2ch 24bit.
Do you have the same output sample rate set as the tracks are?
OK I see where in the Audio Midi setup I can adjust the digital output. The output is set to 44100.hz and 2ch 24bit.
googlebot: I'm ripping my CDs into FLAC files using XLD and I don't see what the sample rate is. I guess I just assumed they were at 44.1KHz but I'm trying to figure it out now.
Thanks again guys..
Question: why do you use the analog audio output which is coming from the Mini's amplifier which I'm assuming is not very good? I haven't done that (except to test) because I assumed the audio quality was low.
You should not make this assumption.
Question: why do you use the analog audio output which is coming from the Mini's amplifier which I'm assuming is not very good? I haven't done that (except to test) because I assumed the audio quality was low.
You should not make this assumption.
Ok, does than mean that in the case of the Mac mini it's not true?
The Mini's analog output from the headphone jack has been amplified by the Mini's internal amplifier. So I'd be feeding an amplified signal into my stereo preamp. Doesn't putting the Mini's amplifier into the process degrade the final output from my home speakers?
That's why I was looking into buying the external DAC/Music Streamer like the HRT model I cited. That way I could take a preamp audio output from the Mini (bypassing the Mini's internal amplifier), then do the DAC process in the HRT (or similar) box, and feed the analog audio (still preamp) signal into my stereo preamplifier.
So are my assumptions incorrect?
Thanks again for taking the time to help.
I use the analog audio output because i don't use my MacMini for anything that requires surround sound. It may feel it doesn't sound as good because the output levels are pretty low. If you were to volume match the digital with analog you would be hard pressed to hear a difference thats if you even could.
pgm234,
Please read TOS #8 (http://www.hydrogenaudio.org/forums/index.php?showtopic=3974) and the following thread:
http://www.hydrogenaudio.org/forums/index....showtopic=16295 (http://www.hydrogenaudio.org/forums/index.php?showtopic=16295)
They should be kept in mind when trying to justify assumptions about audio quality.
What i actually do is use the analogue out into my amps Main In, sounds amazing and the Mac can be used to control the volume.
I don't know enough about this stuff so I'm learning I shouldn't make assumptions about what will sound good and what won't until I try it.
You should also be aware that you cannot be sure of what you actually hear if you know ahead of time which setup you're listening to. If you have some type of expectation bias your brain can and often will play tricks on you (http://www.youtube.com/watch?v=ypd5txtGdGw).
What i actually do is use the analogue out into my amps Main In, sounds amazing and the Mac can be used to control the volume.
Billy, thank you again for taking the time to help me. I'm going to try to do an unbiased sound comparison. It would be great to save the cost of the external DAC if it doesn't improve the sound quality. And your solution definitely solves the main problem I have with my preamp being slow in resyncing with the audio input.
Another solution is to use a Airport Express, that will bypass the MacMini's internal sound processor, some say this is the way to go to get the best possible sound. I honestly can't hear any difference between that and going straight from the analogue our to my amps Main In. If your amp doesn't have a Main In then APE may be the cheapest solution.
Edit: The Apple TV is cheaper than the APE and will do the same thing plus so many extra features.
Normally a CD is ripped to its native bit depth and sample rate: 16 bits / 44.1 kHz
You might try these settings in the audio midi.
Some audio drivers do mute the digital out between tracks.
If for some reason the McIntosh is very slow in locking on the signal this might explain the drop-out.
However I would expect this not to happen in case of gapless playback.
If you connect the 2 analogue, is gapless really gapless?
I also expect this to happen at the beginning of the very first song.
No ‘enhancements’ active like fading?
some say this is the way to go to get the best possible sound.
Not to belabor the point but some also say you need magic pebbles to get the best possible sound.
Is anyone actually silly enough to believe that pebbles are magical and can improve sound.
Unfortunately yes and for this reason I think the old "some say" does a disservice to this community. Let's stick to verifiable facts, please. If you have objective evidence that an APE does a better job converting digital to analog than a Mac Mini then feel free to present it.
I have no evidence, i doubt very much i could come up with any, i personally can't tell the difference between the MacMini or APE. No scientific tests but it all sounds the same to me. I just suggested the APE as a way to overcome their issue.
The Apple TV is cheaper than the APE .
People at Apple site and stores don't think so...
I am using a brand new Mac Mini (4GB RAM running OS 10.6.5) to run primarily FLAC audio tracks to my stereo system’s preamp, a McIntosh MX132 via the TOSLINK digital audio out.
The problem is that at the end of every song, it seems like the Mac Mini stops sending the audio signal to the preamp during the “gap” between songs, as evidenced by the L/R audio input indicator lights on the front of the preamp going out. When the next song starts, it takes about 1-2 seconds to re-establish the connection (i.e., for the indicator lights come back on on the preamp) and so I don’t hear the first second or so of that next song.
Just now remembering some time ago I read a Stereophile review of the Airport Express reporting this same behavior and in fact they attributed the problem to the ceasing of digital signal output from the device between two songs, coupled to the delay of the feeded DAC to resync in time from the start of the next song.
Here's the exact excerpt:<<One operational glitch that didn't affect my system to any significant extent but did do so for some readers was the fact that, as the AE doesn't have a local clock circuit, when the incoming data is interrupted, as it is when you change songs in iTunes, there is no longer a digital output to feed the DAC, which loses lock as a result. Both the Levinson and the Benchmark DACs that I use deal gracefully with the lost lock and are quick to unmute when the new song is sent to the AE. I therefore missed the fact that with some other DACs, the first seconds of a song might be cut off.>>
Another solution is to use a Airport Express, that will bypass the MacMini's internal sound processor...
There is no sound processing in a Mac mini, when the digital output is used, the sample rate matches, and volume is set to 100%.
I suspect the McIntosh to employ some queer sample rate detection mechanism. S/PDIF normally doesn't know a "connection" state, samples are supposed to be played as they come. Maybe the McIntosh tries to "improve" this simple mechanism by trying to detect the sample rate for reclocking and then chokes on a microsecond delay between the end of the last and start of the next track. I would seriously reconsider using the McIntosh for D/A conversion if you cannot identify audible benefits.
I suspect the McIntosh to employ some queer sample rate detection mechanism. S/PDIF normally doesn't know a "connection" state, samples are supposed to be played as they come. Maybe the McIntosh tries to "improve" this simple mechanism by trying to detect the sample rate for reclocking and then chokes on a microsecond delay between the end of the last and start of the next track. I would seriously reconsider using the McIntosh for D/A conversion if you cannot identify audible benefits.
I'm pretty convinced that you're right, my problem is with the McIntosh's limitations in handling the digital/optical audio input.
So I think I've narrowed this down to two solutions.
1. Feed audio from the Mac Mini's headphone jack using a 3.5mm-to dual RCA splitter into the analog input of my preamp. Alternately, I could take the Mini's audio output from its USB port to an external USB DAC, and from there run analog R/L audio cables to the preamp. If I use the external DAC, I should still be able to use the Mini's digital/optical output for movies as the issue with the delayed sync between the Mini and my preamp is not important with movies (I don't care if I miss the first second of a movie's audio). So for the movie side, I still can have 5.1 audio output to the preamp.
2. It was suggested to me that AppleTV would work, that its digital/optical output would not cause the sync delay problem. It's only $99 and if it doesn't work I can always return it. However, the ATV choice carries pluses and minuses. First, my 1000+ album collection is all in FLAC. I could run Fluke under iTunes or use Max and convert everything to ALAC. I haven't tried Fluke but it seems like some users at least have had issues and it's just another added complexity.
Also, I've been using Songbird and I really like it. iTunes seems to be a step backwards, especially with a large music collection as its sorting capabilities seem limited, but maybe I just need to play with it more.
The advantages of going the ATV/iTunes route are: (1) hopefully the ATV output solves my optical input problem; (2) I get to use the features of ATV (I'm just not sure I need/want any of them); (3) I have an all-Apple solution so hopefully future technical issues are minimized, as opposed to a mix of systems and apps; (4) the ATV user interface is easy and my wife will like it.
Anyway, thank you again to everyone for the terrific help. I think I’m close to having this issue solved.
Unfortunately yes and for this reason I think the old "some say" does a disservice to this community. Let's stick to verifiable facts, please. If you have objective evidence that an APE does a better job converting digital to analog than a Mac Mini then feel free to present it.
There are different utterances in which "some people say" occurs. If billytheonion had said "Some people say magic pebbles improve SQ, so you might try that," he would clearly have been trying to sneak round TOS #8. But he actually said "S.p.s.t. <x is better>, but I can't hear it." In that case, s.p.s.t. is clearly equivalent to "You will find some claims on the internet or in magazines," which is an entirely empirical statement, especially as the obvious implication of "but I can't hear them" is that such claims should be subjected to test.
Objecting to forms of words, rather than what the words are used to say, can end up in a Scunthorpe situation.
He did in fact offer up the AirPort Express as a solution, though I don't think he was intentionally trying to sneak around TOS #8 and to be clear, I was not calling him out on a TOS #8 violation; rather I was attempting to inquire as to whether he noticed that people making such claims also had objective evidence supporting their position. Somehow this is wrong but yet it is perfectly fine to drop the idea that magic pebbles might improve sound quality so long as I stipulate that I don't have the ability to tell the difference?
Let's talk about the spirit of what I was trying to get across instead of nitpicking the language that I used. Would I have garnered your approval if I had said, "I find third-party claims about needing an AirPort Express to get the best sound quality dubious and would like to see some objective evidence in order to take them seriously. I think this community is better served without their presentation if they cannot be substantiated in accordance with our Terms of Service."?
If billytheonion feels that I was accusing him trying to avoid a TOS #8 violation then I extend my apologies, though it is pretty clear to me from his response that he did not take it that way at all. On the contrary, it seemed quite obvious that he was extending at least some credibility to what others have been saying. Again, if this assumption is wrong I further apologize to him. Perhaps I should have prefaced my reply which you found offensive with an acknowledgment that he took the time to suggest differences between alternate solutions are probably not audible as far back as his second reply in addition to crediting him with identifying the problem in the very first reply to this discussion.
Yea sorry about that, didn't realise they lowered the price of the the APE, i still feel the Apple Tv is a better buy only few extra $$ and so much functionality.
Quote" There is no sound processing in a Mac mini, when the digital output is used, the sample rate matches, and volume is set to 100%." In my poor english way thats what i meant.
No i don't feel that anyone was accusing me on anything, i understand what Greynol was getting at. Lots of claims are rubbish and that there is no need to bring them up here. Just because people say this is better doesn't mean it is, especially with no evidence.
Converting all your Flacs to ALAC is an option and using iTunes. If you need any help organising iTunes sing out, i find it has more than enough options to keep your music very well organised. I do have an Apple Tv 2 and it doesn't cause the signal to drop out, so hopefully that solves your issue. Once it's set up there is no need to have the TV on either and can be controlled via your computer or an iDevice iPod Touch iPhone or iPad.
The advantages of going the ATV/iTunes route are: (1) hopefully the ATV output solves my optical input problem; (2) I get to use the features of ATV (I'm just not sure I need/want any of them); (3) I have an all-Apple solution so hopefully future technical issues are minimized, as opposed to a mix of systems and apps; (4) the ATV user interface is easy and my wife will like it.
A noticeable difference between Apple TV and Airport Express is the lacking of analog line level output in the ATV. I don't know if the ATV will solve the optical link issue, but surely with the AE you could get rid of it using its analog output to drive your preamp. About the overall quality of this solution, of course, it's up to you to decide if the AE internal converter can take the place of the preamp one in your setup. Anyway, knowing the first and not the latter, I can only hypotize that you're not going to notice many differences, if any.
I still see both AE and Apple TV for $99 at Apple. Are you guys probably seeing the refurbished prices? I bought a refurb AE on ebay for about $60 IIRC.
I still see both AE and Apple TV for $99 at Apple. Are you guys probably seeing the refurbished prices? I bought a refurb AE on ebay for about $60 IIRC.
Here, in Italy: Airport Express 89,00€ - Apple TV 119,00€.
The dish of pasta all'amatriciana I've just eaten: 3,50€.
I installed Apple TV last night and ran its digital/optical output to my preamp and the problem did not go away. My preamp still loses sync and takes just long enough that I don't hear the first second or so of the next song.
So that leaves me with the alternate solution of either using the 3.5mm-to-RCA splitter off my Mac Mini, or buying an external USB DAC, and running analog R/L audio to my preamp. AE doesn't gain me anything because my Mac Mini is located next to my preamp and I can just as easily run the analog direct from my Mini.
I'm going to try to contact McIntosh to see if they know of any solutions, but with such an old preamp I'm not optimistic. They'll probably recommend upgrading to a new one but if I did buy a new one I can't afford their model.
Strange issue, i have an Apple tv connected to my HK amp no issues and even my NAD has no issues. Deff seems like an issue with your amp.
I would just go from 3.5mm-to-RCA splitter to your preamp, that way you can use the MacMini's volume. It's all going to sound the same. Great quality. No scientific test i have tried many ways of connecting to the amp and to me they honestly all sound alike.
Too bad the Apple Tv didn't solve the issue, there is really nothing on the Mac that has a UI and good as the Apple TV for music.
Strange issue, i have an Apple tv connected to my HK amp no issues and even my NAD has no issues. Deff seems like an issue with your amp.
I would just go from 3.5mm-to-RCA splitter to your preamp, that way you can use the MacMini's volume. It's all going to sound the same. Great quality. No scientific test i have tried many ways of connecting to the amp and to me they honestly all sound alike.
Too bad the Apple Tv didn't solve the issue, there is really nothing on the Mac that has a UI and good as the Apple TV for music.
A few people told me that Apple TV worked for them, so I'm pretty sure it's just the slowness of my old preamp. I bought it back in 2001 so maybe it's just too slow to handle the input properly.
My wife loved the Apple TV UI. I thought it looked really good and was simple and straightforward, but I don't mind using the full iTunes. With so many artists in my library it's sort of a pain to scroll using the remote. I would need to work on the tagging so I could use genres more effectively to find music. It was really cool too how she could stream music from her iPhone, but even that had the sync issue at the start of songs.
So thank you again for the continued help, I'll work on the analog option next.
The Apple TV 1 will deff solve the issue that has analogue, maybe you could find a cheap second hand one. with the internal HDD and you can add an external, you can avoid leaving your mac on too.
Yea you must make sure the tags are done properly for it to show up on the Apple TV correctly. With the search function you can just type in what you are searching for no need to scroll down long lists. I have really found nothing that compares to the Apple TV UI for music
Finally! The problem is solved. I’ll document the fix here for archiving purposes in case someone in the future comes up with the same problem. Thank you to everyone for all the help and suggestions. Apple TV didn’t solve the initial problem, but it did make me get Apple TV which turned out to be a great purchase especially for my wife who loves it.
The problem was indeed with my McIntosh MX-132 preamp/AV Processor. However, it was not due to the unit being “slow”, it had to do with one of the settings.
Bottom Line: go into the MX-132’s Settings and set DTS Unmute Delay to “OFF”.
In the words of McIntosh Tech Support: "DTS Unmute Delay is feature from the days of the first Multi Channel digital music format: DTS Audio. Sometimes a processor will incorrectly try to decode DTS as Dolby Digital or PCM, this can cause a short burst of White noise before the processor correctly identifies the signal as DTS. To avoid this noise, DTS UNMUTE DELAY mutes for a second or 2 when a new digital format is detected or, as I suspect with your system, the digital stream stops entirely between songs and the MX132 has to once again decide what format it is looking at. So songs have the first note or so cut off by DTS Un-Mute Delay, that is why we added the ability to turn it off.”
This feature was actually added in a later software release to the MX-132, so it’s not covered at all in the manual and I could not find any online documentation. That’s why I couldn’t find it earlier. It can be found under Option 9 in Setup (ADVANCED). If Option 9 says “RESERVED”, it means you have an earlier software version and you need to upgrade the unit (done via the RS-232 connector in back) to get this option. Luckily mine had it, as I would have had to bring the unit in because I haven’t had an RS-232 connector in a long time.
After turning this feature off, everything worked great last night. The by-product of all this is that I have now made the switch all the way to the Apple side, switching from Songbird to iTunes, and using Apple TV which my wife loves. Instead of reading the more complex iTunes display and using the Bluetooth trackpad and keyboard, we just use the simple Apple remote and Apple TV to control music. And if I want, I can switch the display to the Mac Mini and use iTunes via AirPlay and that works great too.
Thank you to everyone for all your help and patience as I worked my way through this issue.
Fantastic news, turned out all excellent in the end.
I also love the Apple Tv for streaming music, the UI is so well thought out and works with iTunes seamlessly.
You can also use your iPhone to browse your music and airplay it to the AppleTV.
It seems that S/PDIF modules built in personal computers or home theatre systems have a very annoying energy saving feature : at the shortest, slightest perfect pause they switch off transmission - and they need 500-800 milliseconds to restart transmission. It's a big shame to the audio industry, and manufacturers are okay with this.
So my final solution was to write an application, that generates an absolutely unhearable tone - 200 Hz, 8 bits per channel, pulse levels are 0 and 1, volume is 1 percent - I maxed out my LG home theatre system's volume, and I couldn't hear it - and it keeps the S/PDIF module alive, no more pauses, breaks, silences, everything is fine.
I put it up on the Mac App Store : Optical Audio Port Keepalive (https://itunes.apple.com/us/app/optical-audio-port-keepalive/id726983900?ls=1&mt=12)