Ayre DX-5 bluray player - Page 39

Hi Charles,

I will check, thanks.

I am still considering to use the HDMI Audio only output for movie watching too. However, this would require a direct connection of the DX-5 (HDMI A/V out) to my Sony beamer with an approx. 20m HDMI cable (Currently I have both HDMI outputs of the DX-5 connected to my Marantz AV pre and can only switch between them). Do you think such a long cable will be handled by the DX-5 or will the picture quallity be degraded already? And how about lipsync if sound and picture travel through different cables to different units?

Best regards

Ingo

Lieber Ingo,

twenty meters is very far for copper HDMI. But it is nothing for optical HDMI. The optical cables are less expensive now. Buy one of the Opticis ones. If you remove the current limiting resistor, you can power it with the DX-5. The picture will be better with the long optical cable than the shorter copper cable. The repeater amplifier in the SSP will degrade the video signal even more.

It's been a while since I looked at it, but there are two models. One is the hybrid where the four video signals are optical and the CEC signals are copper. Then there is the one that is purely optical. The pure optical cable will give the very best performance, but only if you replace the supplied switching supplies with linear power supplies. With the hybrid cable you only need power at one end as they can send power down the copper portion of the cable. But with the purely optical cable you need power at both ends to supply the electronics used to convert electrical to optical and vice-versa.

You can have Philipp remove the current-limiting resistor and supply the end at the player with the linear supply in the player. Then use it with the switching supply at the projector end. Finally, when you have the time and/or money, replace the switching supply at the projector end with a linear supply and there will be a further improvement. The picture quality will be much better. You will doubly isolate the switching supply in the projector from the rest of the system -- once with the optical cable, and again with the isolators in the DX-5. The optical cable has a much wider bandwidth than the copper cable. You will have one cable and set of connections instead of two. You will eliminate the electronics in the Marantz from the optical path. Finally you will replace the switching supply at the projector end and eliminate another source of RFI that contaminates everything connected to your AC mains. That is definitely the way to go.

Once you have the cable, you can try a second experiment. Just disconnect the projector from the AC completely so that it is not creating any interference. Then just play some music you love on the DX-5. Compare using the copper cable from the HDMI Audio-Only to using the optical cable for the audio signal. I am confident that you will hear another large improvement. You may end up purchasing two of the Opticis cables, one for the audio and one for the video. That would be the ultimate. After you have tried these things, be sure to let us know what you have found.

I have not done these experiments for many years. When I did it, the only video connection available was DVI and the only cable was the hybrid.. The improvement in picture quality was significant. Now they have the pure optical cable. Now they send the audio over the HDMI also. The only way to get better sound would be to use the analog audio outputs, but then you are limited to two channels. For surround sound use one optical HDMI for the video and another optical HDMI for the audio. Just buy one at first as you will be able to test them. If I am crazy, you can tell me. But I think it won't be very long before you buy the second optical cable.

Best regards,
Charles Hansen
Ayre Acoustics, Inc.

Hallo Charles,

many thanks, interesting idea, I received a opticis price list, and they are not too expensive anymore, especially for the basic model M1-2000-20. However, their technical specification is HDMI1.3 and unfortunately they did not answer my question whether their cables support 3D-BluRay, which normally requires HDMI1.4. For such accessory stuff I'd like to have full compatibility at least with current standards (and how about future 4K displays/projectors...), although HDMI1.4 is not required for the DX-5. However, I will keep an eye on these cables.

Speaking of isolation from switching power supply interference, I use two independent systems for music listening and home theater. These are only brigded by the symmetrical cable from the AV Pre to my Levinson 326 Pre (main channels, SSP Mode, like the AYRE preamps) and by the DX-5's HDMI connections. I fully isolate my music system by the Mudra Akustik Powerbar Max (http://mudra-akustik.de/index.php/products/powerbar-max) and the fact that the DX-5 has galvanic separation between video and audio (if I understood correctly) was a prerequisite to buy it (and I was not disappointed ). The home theater part consists of four additional disc players (BD, HD-DVD), a HDD recorder, Beamer, TV-set, and a separate active HDMI switch together with the Marantz AV pre/power amp. So full isolation here would require several optical HDMI cables...maybe too expensive for the purpose...

I have not yet found the time to check the BOARDWALK EMPIRE BDs further, but the weekend is on its way...

Schöne Grüße aus Köln nach Boulder und ein schönes Wochenende wünscht

Ingo

Lieber Ingo,

I spent some time re-acquainting myself with the Opticis product line-up for HDMI. They basically have three different products:

1) The HDFX-200-TR -- This is the only one that is purely optical, with NO copper cables to conduct any interference.

2) The M1-2000 -- This one is very small and the conversion boxes at each end are small enough that they do not need to be removable.

3) The M1-2R2H-TR -- This one appears to be the oldest one. It has a hybrid optical/copper construction and the conversion boxes at each end are quite large.

As I've noted previously, the only one I've had direct experience with personally was an OEM version of the Opticis conversion boxes marketed by Fujitomo, with bright orange hybrid optical/copper cable, back in the days of DVD using DVI. Even with the partial copper construction, this cable gave a significantly superior picture quality to any other DVI cable I have ever used. We had a 100 meter cable on loan to us from Fujitomo and it was quite surprising at how much it improved the PQ.

With the current Opticis cables, I would only consider the first two models. There seems to be no reason to use the third one (unless you already own it, in which case I'm sure that it is a fine performer).

The second model has the advantage of having the lowest power consumption of all three models. The total draw for both conversion boxes at +5 volts is only 280 mA, and I am confident that if Philipp removed the current limiting resistor, that you could run the cable from the linear analog supply built into the DX-5. (This supply is there for one reason only. If the display is powered off completely, it supplies power to the memory built into the display that describes the capabilities of the display. Then when you turn on the source, it can read the capabilities and send the highest quality signal possible to the display.)

On the other hand, I am equally confident that the first model (which is PURELY optical) would give the highest PQ of any of the models. And as noted before, I think the ultimate setup would be to have one of each of these cables going to the display from each source. Then for the audio, use ANOTHER one of these all-optical cables to connect to your SSP. If ANY of your other sources have two HDMI outputs, connect them to your SSP with another pure optical cable. For any source that does NOT have a secondary HDMI output, I would connect ALL of the audio connections to the SSP via TosLink. This would ensure the maximum isolation between the video and audio systems which is CRITICAL for good performance of both video and audio. Yes, you would be limited by some of the formats when using TosLink, but the only other way to do it would be to run the PURE optical cable from the source the SSP, and then another PURE optical cable from the SSP to the display.

The disadvantage of this plan is that you are going through three scaling chips and video amplifiers -- one in the source, a second one in the SSP, and a third one in the display. The one in the DX-5 is as good as it gets. So you ideally want to set that one to the native resolution of your display and go STRAIGHT to the display. Going through the extra circuitry in the SSP will result in visible image degradation.

~~~~~~~~~~~

Regarding HDMI 1.3a versus HDMI 1.4, Wikipedia (generally VERY reliable) specifically states, "High Speed HDMI 1.3 cables can support all HDMI 1.4 features except for the HDMI Ethernet Channel". There are three footnotes to support this claim, and you can read it at:

http://en.wikipedia.org/wiki/Hdmi

While I have not performed the experiment myself, I can pretty much guarantee you that running 100 Mbs Ethernet mixed in with the picture is going to result in degraded PQ. I would NEVER combine the ethernet with the rest of the HDMI signals. The only reason that they have done this is so that the average idiot consumer can connect his video system with ONE cable to provides all functions. But I am fairly confident that anybody reading this forum would have NO problems whatsoever connecting two cables -- an HDMI cable and a separate ethernet cable without getting it wrong!

I have to admit that I don't know what exactly is meant by "High Speed". If this affected the ability to run 3D, I am sure that the Wikipedia article would have mentioned it. I suppose that it is possible that it would affect the ability tor run "4K" video, but I don't think we will be seeing a huge selection of 4K titles available any time in THIS decade!

You have to remember what drives all of this silliness -- MONEY, pure and simple. Learn from the past so you don't repeat the mistakes of others (or even worse, your own mistakes).

When DVD was released in 1997, players sold for between $800 and $1000. The top line Sony was an excellent machine, and they sold it BELOW their manufacturing cost to try to help promote the format. It was an excellent machine and set the benchmark for several years. Prices slowly declined. By 1999 a good DVD player was $300 to $400. By 2001 they had hit $200 which was pretty much the "magic" price where EVERYBODY could afford one as an "impulse" purchase.

But then they screwed up. They started selling format licenses to the Chinese. In another year, you could buy a really crappy player (that didn't even have a front panel display -- it was all on the display screen of your TV) for $49. At that price NO quality manufacturer could make money. THAT was why Blu-ray was invented. The Japanese majors wanted to make video disc players into a profitable item again. (They tried it first with DVD recorders, but those flopped miserably.) Blu-ray has only been moderately successful, but it only took a year before the Chinese made it a "bottom feeder" commodity item selling for as little as $100.

Next they tried to make it more profitable by adding 3D, but this was just a move of desperation. Nobody really takes it seriously -- not the manufacturers, not the consumers, not the movie studios, not the directors. It's just a last gasp of trying to make a few more dollars from a video disc format before China Inc. destroys Japanese manufacturing. Do you KNOW how many factories were destroyed in the Tsunami that will NEVER be rebuilt? Toshiba used to make the best TosLink transmitters and receivers. That factory was badly damaged in the earthquake. They are NOT going to re-open the factory, because it would lose money for them. Nobody wants to pay $0.25 for a high-quality TosLink transceiver, when you can buy an "adequate" Chinese TosLink transciever for $0.05. It's the "race to the bottom", and it's driven by all the consumers that think that $500 for a Chinese Oppo is absurdly expensive. (One hesitates to even ask what they would make of a $10,000 Ayre BDP!).

So even if somebody releases hardware and software for 4K video, it is not going to go ANYWHERE. The studios in particular are VERY wary of releasing the original master files of the movies for the Chinese to rape and pillage. It wouldn't even be noticeably better until we got to 100" or even 150" screens. Now you are limited to projectors instead of flat panels, and panels outsell projectors by 100 to 1. People who think that 4K is ever going to become a mainstream product have been smoking far too much crack cocaine and suffer from delusions.

And besides, those quantifiable specs have no meaning when it comes to the true performance of a video (or audio) system. The ONLY thing that matters, that is worth trying to pursue is "the involvement factor". When you start playing that music or that movie, are you COMPLETELY sucked in to the music or the plot of the movie? Does EVERYTHING else fade into the background so when the movie is finished it takes a few minutes to return to our "normal" reality?

Or is it the case that when you turn on your system, that your brain keeps thinking about the bills that are due and haven't yet been paid or the jerk at work that is making your job miserable, or that you need to change the oil on your car or that sometime this year that you will need to re-roof the house, yadda, yadda, yadda?

I would FAR rather watch a film on DVD with an Ayre D-1xe on a Pioneer Kuro in HT2.0 than watch the same film on a cheap Chinese Blu-ray player with dozens of on-board switching power supplies and crappy high-feedback op-amps in the SSP and one of those terrible multi-channel analog volume controls that ruin the sound quality. The first would be completely engaging and absorbing. The second would allow you to see the hairs in the actors' noses, but would be about as compelling as watching it in 1080p on a Nexus 7 tablet -- fine for distracting you from the miserable experience that long airplane flights have become, but hardly something that will convey all the power and emotion available a masterpiece film like "Dersu Uzala" or even "Amelie".

Best regards,
Charles Hansen
Ayre Acoustics, inc.
Edited by Charles Hansen - 4/6/13 at 10:17pm

Addendum to previous post regarding Opticis HDMI cables.

The first model on their website (that is fully optical comes) with two power supplies that can deliver 1 full ampere at +5 volts. I don't know how much the actual current draw is, but I would doubt that this could be supplied solely by the supply in the DX-5. Therefore to achieve the highest possible level of performance, one would eventually want to replace the switching power supplies (one at each end as there is no copper connecting the two ends) with linear power supplies.

Best regards,
Charles Hansen
Ayre Acoustics, Inc.

Hi Charles,

many thanks for your additional comments on the optical HDMI cables. I fully understand their benefit but a rough calculation tells me that I'd have to spend >3700€ to replace all HDMI cables in use with the opticis in order to achieve full galvanic isolation. Given the fact that I rarely listen to surround music and surround is limited to movie watching, I feel it is too much for my budget. Currently I'd rather invest in the DX-5 upgrade, a new headphone together with an appropiate amplifier and some other things I need....

Regarding BOARDWALD EMPIRE. I cleared the persistant storage of the DX-5 (although it was nearly empty) and now the discs play fine. Problem solved, thanky you!

I will post my experience with the DX-5 upgrade as soon as it arrives!

Best regards

Ingo

This certainly is an interesting and pretty much unexplored topic from my experience. I did some googling and found well over a dozen makers of HDMI fiber optic converters ranging in price from $263 to nearly $3000. This of course begs the question of how much one needs to spend and where the diminishing return point is. The cheapest is this one for $263 including 75' of fiber optic cable and note that it is not a hybrid copper/fiber connection.

http://www.mycablemart.com/store/cart.php?m=product_detail&p=3570

Itis the only I saw that required a USB power supply. BTW I saw three power supply specs published where the converters required between .1 and .35 amps. It was stated that one would only add the power supply if it the converter would not work without it.

Anyway if these did the job one could follow Charles' suggestions without too much pain. Any reason not to try one of these? The 75' length could be problem but perhaps they can make shorter ones. 10' is all one would need for the gear in the rack.

I am far from an expert on this, but the first I heard about it was from Fujitomo over a decade ago. They used the Opticis converters, which leads me to believe that it is not trivial to run signals in the GHz range! For example, if you look at conventional fiber optic technology, most TosLink connectors can barely get up to 96 kHz (around 6 Mbs). Apparently it is not the sender that is the problem, as lasers can have a very wide bandwidth. Instead it is the receiver that is the difficult part. Normally Japanese companies are VERY reluctant to use outside technology, so I would assume the fact that Fujitomo used the Opticis modules speaks volume of the difficulty of pulling off this trick properly.

Of course the only way to know for sure is to borrow several different cables and compare them... Easier said than done.

A similar problem happened with the Thunderbolt connection developed by Intel and licensed first to Apple. This was originally supposed to be an optical cable, but either they couldn't get it to work right or it was too expensive. However, I have heard that there will be a new generation of Thunderbolt down the road that uses optical technology. I certainly wouldn't purchase any fiber optic cable (with the possible exception of the Opticis) without have a refund policy. You might be able to find out more regarding these technologies from an internet search or Wikipedia.

Charles Hansen
Ayre Acoustircsi, Inc.

I am new to this forum but not to the reading of this thread. I have owned my DX-5 for a short amount of time but have loved every moment of it. I do have a couple of questions about the DX-5.

1.) In the manual it says to set the downmix mode to 7.1 instead of stereo but if you read the Oppo 83 manual that this player is based on it says when you are using it in a stereo setup instead of a home theater setup it says to put it in the Stereo downmix mode. What is that exactly?

2.) Is there a huge voltage difference between the RCA connections and the XLR connections?

Thank you for any information. I also have a question on the MXRs and will post it over there.

Jeff Gossett

Looks like I spoke prematurely. I have read the MX-R thread over at audio asylum instead of here. So many forums, I got them criss crossed. I apologize.

Mr. Hansen, would you prefer me post a question to that site or to this one regarding the MX-R? I would not want to skip subjects on the DX-5 thread if that offends anyone.

Jeff Gossett

Hello Jeff,

Thanks for your questions regarding the Ayre DX-5. I'm not quite following you however. Are you connecting the player to a stereo system or a surround-sound system? Which outputs are you using? (There are four audio outputs -- the two-channel analog outputs, the HDMI audio-only output, the HDMI audio + video output, and the AES/EBU output.)
The balanced outputs will provide exactly twice the voltage output of the single ended outputs, as there are two signals that equal and opposite. This is a 6 dB difference in level. It is not "huge", but it is very noticeable. The human ear is non-linear, and generally a signal needs to be 10 dB louder (3.16 times the voltage to sound "twice" as loud).

Each forum tends to attract a different audience. The AVS Forums are almost exclusively dedicated to video systems, and the audio discussions here tend to focus on issues of surround sound.

The Audio Asylum appeals to very discriminating listeners and for the most part ignores video. One advantage of the AVS Forum is that a thread will stay active forever. For example, this thread is many years old and serves as a great repository of knowledge regarding the DX-5, as almost nothing else is discussed on this thread. Whenever somebody posts to it, it will move to the top of the "active" list. In contrast, the threads on the Audio Asylum usually stay active for a few days to (at most) a week and then they "disappear" and fall off the radar screen. So often the same subjects get discussed repeatedly. If you use the "Search" function, you can find a lot of information from older threads, but this is sometimes not so convenient. I will go look at the Audio Asylum and look for your question there regarding the MX-R.

You can post anyplace you like. I get an e-mail every day that notifies me when a post is made to this thread. I usually check the Audio Asylum once or twice a week, but sometimes will miss a discussion there.If you have a specific question, often it is best just to call the factory, as we have an excellent customer support department. If you are in a different time zone, we have recently added an e-mail contact form to our "Contact" page.

Hello Jeff,

I went over to the Audio Asylum for the first time in a week or so and couldn't find any posts regarding the MX-R. I tried the search function (but only searched for "Ayre") and didn't find anything either. You could ask the question here, post a link to the other site, or just call the factory.

Best,
Charles Hansen
Ayre Acoustics, Inc.

I will post on the audio asylum forums later today. Thank you for your response.

Here is the link to audio asylum.
http://www.audioasylum.com/forums/amp/messages/18/185118.html

I look forward to our continued dialogue.

I use what you call home theater 2.0. Just a 2 channel setup for watching movies. On page 86 in the manual it says to set the speaker configuration to 7.1 under the "down mix mode" option list.

In the oppo manual for the player the dx5 is based on, it says that if you are using a stereo setup to select "stereo" and not the 7.1 mode. I was wondering why this was and what were the technical differences if both are output in stereo. Is it only for the lfe mode mentioned in the manual or was there another reason?

Also, is there a way to measure the dc voltage coming from the dx-5? Just curious.

Hello Sword,

I also prefer HT2.0. It is very simple and very satisfying Also for a given budget, one can achieve a higher level of sound quality. For $10,000 one can purchase an excellent pair of stereo speakers. But to purchase 7 speakers and a sub-woofer for $10,000, the quality will be good but not outstanding. But I also understand that satisfaction that surround can provide.

~~~~~~~~~~

The difference between the Ayre and the Oppo comes from where the signals are derived. The Oppo has two audio DAC chips, one for stereo and a second one for 7.1 channels. The stereo DAC chip always receives a two channel mixdown, while the multi-channel DAC chip receives the same signals that are sent to the HDMI output. In the Oppo manual, when it tells you to select "stereo", the main processing chip will create a mixdown of all the channels into two channels and send this signal to the HDMI connector also.

But the Ayre is connected differently. Our analog circuit uses the same two-channel stereo mixdown that the Oppo two-channel DAC chip uses, although we add some nice features (such as optionally adding in the LFE effects when a movie has been improperly authored). Then the HDMI Audio-Only Output uses the signals that were previously sent to the multi-channel DAC chip. There is never any reason to down mix this output to stereo, as there is no SSP in the world that has two-channel performance as good as the built in stereo DAC in the DX-5. If you are going to listen to any meaningful amount of two-channel material through a multi-channel system, I STRONGLY recommend that you spend the money to purchase a nice stereo preamplifier with a processor-passthrough mode. Even the $3500 Ayre K-5xeMP will provide a significant step up in sound quality over the best SSP's, and in the grand scheme of things, this is not a great deal of extra money in an ultra-high performance system like this would be used for.

If you at the beginning of the section of the Ayre manual that you refer to it says:

“Speaker Configuration” applies only to the HDMI
Audio Output and LFE Mixdown mode. The other
digital outputs and normal operation of the Analog
Audio Outputs are unaffected by these settings.

By setting the player to 7.1 channel mode, it will deliver ALL of the channels that are available to the HDMI connectors and also any bass that was mistakenly sent to the LFE channel (sub-woofer channel) back to the main speakers where it belongs.. Generally Blu-ray discs will have 7.1 channels, DVD's and multi-channel SACD's will have 5.1 channels, and CD's will have two channels. But all available channels will be sent to your SSP. Please also note that all encoding formats (eg, Dolby TrueHD, dts-HD Master Audio, et cetera) will be decoded by the player and sent to the SSP as PCM. This will allow older processors that don't have the newer decoders to still play all of the sound tracks on any disc, as PCM is sort of a "universal language" for digital audio.

Sure. Just turn on the unit and let it warm up for at least 30 to 60 minutes. Then with NOTHING connected to it (except the power cord), and no discs playing, touch the ground probe of a voltmeter to the gold-plated "shell" of one of the RCA audio connectors. This is connected to the analog ground. Next, with the meter set to either DC Volts or DC millivolts, touch the probe to pin 2 of the XLR output of one channel (the "hot" or + signal) and then touch it to pin 3 (the "cold" or - signal). Repeat it for the other channel. All four pins should be less than 10 or 15 mV and the two phases of one channel should be within 5 or 10 mV of each other.

It won't cause a problem until it is much higher than this. At 50 to 100 mV of offset, you will hear a "pop" when muting or un-muting that input. Past 100 mV and it will likely activate the DC protection circuitry of an Ayre power amp.

Best regards,
Charles Hansen
Ayre Acoustics, Inc.

Hi Mr. Hansen,

Here is what I have on my dx-5.
Right pin 2-10.6
Pin3-23.5

Left pin2-15.6
Pin3- 44.5

I thought that was interesting.

Out of curiosity, when I play CDs the volume is much louder than blu rays. I know part of that is the actual disc but it seems drastically different in volume between CDs and blu rays. What causes a 15-20 db difference? Is there anything in the player or preamp that can cause that or is it only dictated by the disc?

Again thank you.

Hello Sword,

Regarding the DC offsets, that is a bit more than I like to see. It won't hurt anything, but you will almost certainly hear a small "click" or a "pop" through your speakers when you mute the system when the DX-5 is selected as the source. Since you are using the 2-channel analog outputs, I would imagine that you are going to upgrade the unit to the "DSD" version. If you do, that will help in two ways:

a) When it is back at the factory we will re-set the DC offset. That is just standard procedure for any unit that comes back for any reason, along with a full test on the Audio Precision to check for anything else that might be off.

b) We added some heat shields that holds the analog circuitry at a more constant temperature. This reduces any DC drift due to changes in temperature and will help keep the DC offset closer to zero.

I don't know if you have been keeping up with this thread, but most of the posts in the last few months have focused on the changes for the upgraded version. I think post #1084 has a summary of the changes for this upgrade:

http://www.avsforum.com/t/1181755/ayre-dx-5-bluray-player/1080#post_22998931

Regarding the level of the disc playback, the only thing that can affect the output level of the player is if you have engaged the LFE Mixdown mode. This reduces the output level by -6 dB and the front panel LED will glow red to remind you to take it out of this mode when it is not needed. The main reason that Blu-ray discs are so much quieter is that they have 24-bit data. This gives them an extra 48 dB of dynamic range (at least in theory). So to make the movies more impressive, they will mix the normal dialog at a relatively low level. Then when there is an explosion it will be MUCH louder (and presumably MUCH more impressive). CD's have gone in the opposite direction. The theory there is that the louder a CD is, the greater the chance that it will attract your attention when played back on the radio. This is supposed to boost the sales of the disc, and it has really gotten out of control in the last five to ten years, where the entire album is often recorded within a few dB of the maximum output level.

So unfortunately, you are correct -- there will usually be a fairly large difference in volume level between a modern music CD and a Blu-ray movie disc. If you use a computer to play your music, you can use a feature called "Replay Gain" that is designed to even out these things. I don't like to use it as the volume adjustment occurs in the digital domain, reducing the resolution of the playback system. But if it bothers you a lot, you can try it and see if it is worth it to you.

Best regards,
Charles Hansen
Ayre Acoustics, Inc.

Hi Mr. Hansen,

Once again, thank you for your response. I wish I could pay for an afternoon of your time to ask you so many questions about your products and the more technical aspects of them. A factory tour would be incredible along with that. I asked my wife, "Are MXRs gorgeous to you as they are to me?" Of course she didn't consider electronics "gorgeous" but the inside is just as gorgeous to me. At least i dont have to deal with the wife factor as so many have.

Anyway, I am enamored with them. The fact you split the power supplies for positive and one for negative to fit them inside the dimensions of the aluminum block for manufacturing costs is just cool.

Thanks for answering my questions. I have a few more about the dx 5 based on some posts here. Also, I will be getting the upgrade soon. I am very familiar about the details of the upgrade because of your previous post.

My wife didn't want to be out our player until after our child is born. It will be our 10th so she wanted the younger kids to have movies and music to enjoy the first couple of days. Have a good night.

I spent time today experimenting. If curiosity kills the cat, I used up its nine lives today.

You covered why the discs are louder than some versus others. What inside the player changes the DC offset of the DX-5 while watching movies versus CDs. Is it the same as you mentioned above regarding the discs? The reason I ask is because while playing a CD the DC offset never got above the range of 61mV DC that the pin that was 44.5 but when it was playing a Blu Ray movie there was a scene where it shot up to the range of 130mV DC offset for a quick second. I was just wondering what inside the player changes that would affect DC offset temporarily just by reading a disc? I guess I am in this discovery phase about electronics. It amazes me that everything we hear is derived from electrical signals when it comes to pre-recorded material. It truly makes you appreciate the genius that discovered how to record and playback music.

Jeff,

Go back and re-read my instructions. I know I write too much, but you need to read more carefully.

You can only measure the DC offset when no disc is playing.

All you were measuring was the low frequency content of the disc. The meter cannot distinguish between an explosion on the sound track and a pulse of DC energy. So the only way to get an accurate reading is to measure it with no disc playing.

Now go back to work and help your wife get ready for baby #10! (The good thing is that the older ones can help take care of the younger ones!)

Congratulations,
Charles Hansen
Ayre Acoustics, Inc.

I did read it correctly. The first set of measurements was using your instructions.

That is when I became curious as to how much it changed when a disc was playing. That is why I was asking the above questions. I have read all of your posts carefully and thoroughly.

For the record, the only reason I started this exercise is because I like your long explanations.

Also, I even took measurements with the ICs connected with no disc playing to see if the dc increased. Doesn't any increase in dc get transferred through out the system to the speakers unless the amps stop it?

What happens to the DC offset from a source component as it travels through your system will depend on the other components in your system AND how loud the volume is turned up. Generally, the preamplifier REDUCES the level of signsl going through it. Most systems have too much gain already. This is largely due to the fact that when they introduced CD, they set the standard output voltage to be double that of any other source component! (I have no idea why...)

Most products have unity gain at DC. So they will amplify the audio, but just pass the DC on unchanged.

Products with servos will actively cancel DC at the input (up to a certain limit -- usually 1 or 2 volts).

Ayre products will amplify the DC (except for the preamp, where it depends on the volume setting).

The easiest way to judge the DC offset from a source component is to simply mute the preamplifier or switch it to an unused input. This will instantly remove the DC from the system. A small amount of DC will result in a small "tick" or "pop" from the speakers. If you get a loud "thump" or "bang", then there is too much DC from the source component, and it will require adjustment (or rarely, repair).

Hope this helps,
Charles Hansen
Ayre Acoustics, Inc.