Trinnov MC set up guide with SSP and JVB modded Oppo! - Page 2

My simple understanding of the JVB mod is that they tap into the DAC at an exposed point where there is no HDCP. They add four new RCA jacks to send 7.1 S/PDIF. All analog outputs remain functional and all the analog controls (levels, speaker sizes, etc) affect the S/PDIF output. There is is no reclocking. It is a very simple mod and I am not sure even if there is any buffering. They also offer BNC jacks.

Since apparently there were no major changes to the boards of the Oppo 83/93/95/103 they can do the mod to any of these. They have been in business for several years and I do not recall having read anything negative. They can also do a 3G-SDI mod.

http://www.jvbdigital.nl/jvb.asp?cur=2&level=sdi&page=title&title=876

The basic Vanity mod adds a new board. They disable the analog RCA outputs and use them to send 7.1 S/PDIF. They reclock the signal. You can see the board on the one of the links above.

JVB used to modify many more players but the key is that there has be a place where they can tap into an exposed non-HDCP signal. Apprarently most units today have integrated chips making this impossible.

This box converts analog single ended to balanced, not digital 75 ohm spdif to 110 ohm aes/ebu.

Thanks. I corrected the link.

Yes the transformer has a 0.3db loss but as we still get a voltage gain as less current is needed to develop the voltage across 110 ohms. It's still not ideal but better than an unbalanced connection into a balanced receiver. I have used transformers for SPDIF to AES and never had an issue in the past 20 years. 75ohm AES-3 is even easier. Here you simple just need an RCA to BNC adaptor but AES-3 runs at 1 volt versus AES-1992 which runs at 5-10v balanced.

The box you linked to is indeed a better choice.

Look, if the initial suggested lash up works, it won't do any damage to use it. I would just listen carefully for the first month for clicks and pops. You can always add these conversion devices later.

Just a tidbit: The music industry mostly uses balanced AES connections. The TV broadcast industry mostly uses 75ohm AES-3. Go figure! One reason is that AES-3 can be transported and switched through legacy analog video distribution equipment. Not recommended as the rise times get degraded but in small installations it works just fine. AES-3 over coax also has a greater distance limit. This is contrary to analog audio where balanced lines are superior but here the CMR (hum rejection) is not an issue and preserving the rise times is. So for AES the coax is actually a better choice than a balanced pair.

And of course the biggest reason for coaxial AES is cost. A BNC connector costs about $1.00. AN XLR about $3.00. The coax typically used is about $0.25 per foot. The balanced low capacitance ASE cable about 0.90 per foot. Note these are wholesale prices. The labor to install a BNC about 15 seconds. An XLR, about a minute. You get the picture
Edited by Glimmie - 1/27/13 at 11:34am

Well I hope they at least buffer it. A simple emitter follower is the bare minimum. I have built a few small PC boards to convert all my TOSLINK only devices at home to coax.

AFAIK, the digital audio buss which is typically Ic2 or SPI is not encrypted nor is it required to be inaccessible under HDCP. The video is of course.
Edited by Glimmie - 1/27/13 at 12:04pm

I think we are overcomplicating this. When I did my proof of concept, I used a short $5 digital coax to XLR cable (made by Lynx). It worked beatifully and sounded fine. I also tried an adapted (probably the canare). It is restricted to 48/24 and it sounded like crap. I currently use the z-system switcher/converter (I switch multiple digital inputs into my Trinnov) which works fine as well. However, for a single source system (i.e. Oppo -> Trinnov) the short runs coax to XLR (S/PDIF to AES/EBU) will work OK. Curt @ Trinnov also used them.

Here we go with the audiophile voodoo. I doubt the Canare solution "sounded like crap" unless you are referring to the clicks and pops. An impedance and/or level mismatch on SPDIF or AES is not going to increase distortion or alter frequency response. It just can't happen. Poor analog electrical performance will simply induce errors which are audible as clocks and pops or not work at all.

I find it amusing how the ultra high end audiophile crowd can ooh and ahh over some analog RCA cable that costs $5000 and performs no different than a Wall Mart cable. But yet when presented with a cabling problem such as the above where using the proper parts does make an electrical difference in reliability, it's quite OK to use a cheap hack workaround. Oh and then we get the clowns who state you need a true 75ohm connector for AES/SPDIF and that the more common 50ohm is no good. That's also incorrect. Contradicting myself? May seem that way on the surface but again once you get into the math and engineering you will see why impedance matching is important but nevertheless not critical for 1/2 inch in a connector at 6mhz. Now is a true 75ohm BNC connector needed for HDSDI? Damn right it is but now we are at 1.5gbs or 745mhz!

Why are some of these guys so concerned over a 3 foot analog RCA cable at 20khz max yet don't think any of that matters at 6mhz? Reflections, skin effect, well folks that means nothing at 20khz to spite what Audioquest and others say but is another matter at 6mhz which is the -3db point AES/SPDIF operates at.

Just goes to further prove how much the high end audiophile industry is based on fluff and bling versus solid electrical engineering.
Edited by Glimmie - 1/27/13 at 4:01pm

Great to see the discussion on modded Oppo w MC2. I use it here.

I concur with Edorr. I've used the Canare transformers, spec’d at 6mHz bandwidth, are intended for passing 48k digital audio in broadcast applications, not more. Broadcast facilities have lots of 75 ohm running around, so the Canare adapter made moving digital audio very easy. I have four of them here. They are useless above 48/24 audio and indeed sound terrible at 96/24. Give it a try if you like. Someone can buy mine.

SPDIF to MC2 AES in

Trinnov has high bandwidth input isolation transformers (good for 192/24) with the standard AES/EBU 110 input impedance, and Trinnov has designed in significant input sensitivity specifically to accept SPDIF signals. The key is to use short cables. The higher the sample rate, the shorter the cable, and importantly, the less reduced jitter.

What's going on?

The easiest way to describe the impedance mismatch issue is that when impedance is ideal (seldom accomplished, usually some error of low magnitude), the signal flows from end to end with no reflections. If there is an impedance mismatch- from any source, be it a connector, the cable, or the terminations (the end source, in this case 75 ohm SPDIF, or the end = AES 110 ohm), there is a reflection caused. The reflection of the signal then gets mixed with the original signal, causing distortion. Long cables are best served by using an active impedance converter that has the bandwidth required, and short cables doesn't matter. Whats short or long? The typical rule, applied to radio frequencies, is that impedance mismatches don't matter at 1/10 the wavelength or less. For 6 Mhz, this would be 150m. As digital audio is square waves, the rule of thumb is 10x, so this would become 15m, still a considerable length. Of course, we're all looking for excellent performance, so the shorter the better. I believe the best route is to go well inside these guidelines. One can get away with 6' (2m) interfaces, but I prefer 1.5-3’, as it just means less jitter.


MC2 AES > SPDIF

For applications such as an outboard converter. Caution! The Impedance mismatch is easily handled, but the voltage difference is an issue. Where one drops voltages (SPDIF> AES), here you have AES (higher voltage) feeding an input that is easily over-saturated. The input circuit could be damaged by the mis-match. The easiest way to do this is with a resistor bridge that corrects for both impedance and voltage placed at the SPDIF side. Please PM me if you need an example of such a design.

Anyone done any AP measurements? I'd be interested it that...

Cheers-

But how did it sound terrible? Lots of clicks and pops? I agree the canare bandwidth is probably too low for 192k but let's keep in mind digital audio does not suffer from the classic analog distortions. There is a CRC that must be correct in each packet. If not he packet is usually disgarded.

My concern was over the voltage level difference more than the impedance mismatch. If your product has a sensitive receiver circuit then that would negate the issue.

But as a design level EE in the broadcast and mastering industry still don't like the practice of shoving SPDIF into a balanced AES receiver. At the price level of your product I would expect users to do it right so to speak.

Thanks for your offer to buy your Canare transformer but I currently have probably 200 or more in storage. I put in the first Nvision 512x512 AES router in 1993. Currently I manage a 2048x2048 Grass Valley Apex AES routing matrix. I know AES distribution inside and out as well as SDI and HDSDI formats.

Also note that there is a formal 75ohm AES standard, AES-3, which specifically outlines the analog voltage parameters. And it is not the same as SPDIF. And of course there is the old AES-1992 standard which I assume you utilize. The Canare product (and others) are to transition between the two professional standards. They also make a version that handles the attenuation you mentioned.

But as I noted previously, SPDIF is not exactly AES in terms of the transport stream either. It is usually interchangeable but there could be issues. So is the Trinnov true AES protocol or SPDIF. IOW, what exactly do you do with the channel status bits?
Edited by Glimmie - 1/28/13 at 8:44pm

I am blissfully ignorant if electrical engineering. All I can say it sounded fine with the short run adapter cable and not good with the converter. No clicks and pops. Can't say there was any expecation bias because I was kicking back ready to enjoy glorious music when I had plugged in the adaptor. I had no idea what was going on, until Curt pointed out the adaptor is resticted to 48/24.

Do these balance an incoming S/PDIF signal? If so wouldn't they make Canare transformers or outboard converter unnecessary?

Well no. The purpose of the transformer in the input is actually to unbalance the signal for internal processing. What is being suggested comes down to an unbalanced feed into a transformer with the transformer secondary feeding the circuitry. It's not even isolated in that the grounds are tied in this lash up.

But I do agree if you are getting an error free transmission, it will work fine. And as Trinnov states their receiver threshold is low, the voltage level differences can be handled.

Where you can get into trouble here is with ground loops. Yes they still exist in digital systems. They won't put hum in your audio like they do with analog signals but if the "hum" or noise level is higher than half the receiver threshold voltage, it will alter the state of the data bits (turn zeros into ones) and thus induce errors. And here is where a very sensitive receiver can get you in trouble with an unbalanced signal. At higher voltage thresholds, the interfering signal must be that much higher in level to corrupt the data so it is more immune to noise yet now you have a drive problem feeding it with a too low signal such as in the case of SPDIF to AES. A proper balanced connection only sees the difference between the in phase and out of phase signal. The CMR is greatly attentuated.

I'm not trying to put a cloud over this proposed setup. Like I said, it seems to be OK based on the short cable lengths. I'm just warning people what to listen for when first setting up this system in case there is a problem. Don't worry about "sound stage", "fluid high end", and other audiophile terms. because a digital transmission path cannot change any of that. The failure mode is clicks and pops. There are some issues with excessive jitter but these problems are very subtle and IMO, a lab exercise. I don't think these missing 24th bit theories are audible even though they can be measured.
Edited by Glimmie - 1/29/13 at 12:16pm

I am very keen on getting the Vanity digi out board for the Oppo 103 build, because this would allow me to take out my SSP. I would simply run my Satellite TV HDMI into the Oppo 103 and digital out into the Trinnov, and no longer need a processor. Guys that want to keep their processor for advanced bass managent, EQ and input switching could also use the Oppo 103 HDMI in and run digital out into a DRC system WITHOUT downsampling. The Oppo 103 would effectively serve as an HDMI to 4 x S/PDIF converer.

The manufacturer (audiopraise) is currently running a survey on their site gauging interest in a 103 board, which they will build if there is sufficient demand. If you are interested as well, please go to the site and express your interest. You have to register though. If this is too much of a hassle, I guess you can also shoot Pavel an email (ap@audiopraise.com)

The URL is: http://www.audiopraise.com/forum/read.php?9,201

Let's try to make this happen!

To be frank , how can you make use of 8 channels of digi-signals , other than inputting them to Trinnov MC .

It maybe a better solution if a converting board be made to use the existing Vanity93 on 103 .

Larry

If you don't need DRC and can live with the bass management in the Oppo, you can run the digi outs straight into an array of four DACs. If they are identical (or just same brand - say bel canto) DACs, you can keep the volume controls in synch with a single remote control doing volume up down on all DACs. Now your Oppo 103 is a decoder and HDMI input switch. The whole setup will cost a lot less than a very good SSP with no DRC and probably beat the crap out of it sonically.

As I mentioned earlier in this thread, I run digital out from a JVB modified 103 to Trinnov MC and then on (digitally) to Devialet amps.

Edorr, have you compared the JVB digital output mod v the Vanity board? If so, is the Vanity audibly / materially better? Why? Thanks.

There is a Vanity lite board which presumably does what the JVB mod does. It taps into the internal Oppo data stream and feeds passes it through to the RCA connectors as 4x S/PDIF at full resolution.

My only crtical listening is SACD. The more expensive Vanity93 board does reclocking and custom DSD->LPCM conversion. You can compare the Oppo DSD conversion with the Vanity93 board by switching between PCM mode and native DSD mode in the Oppo while playing a SACD. If you use DSD mode the vanity board does the conversion (at 176/24 if selected). If you use PCM mode the Oppo does the conversion (what you get is the same PCM send out when using Oppo HDMI).

The custom DSD conversion is a lot better. I don't know how much difference the reclocking makes relative to the Oppo clocking, because in both scenarios the Vanity board reclocks. So bottom line for a SACD application the Vanity93 board will beats the JVB mod hands down because of better DSD conversion and potentially better clocking. For playing Blu Ray, I don't know but I suspect the reclocking willl give the Vanity board the edge as well. If the JVmod also reclocks (ask them!), there may be no difference.

" I agree the canare bandwidth is probably too low for 192k but let's keep in mind digital audio does not suffer from the classic analog distortions. There is a CRC that must be correct in each packet. If not he packet is usually disgarded."

Are you sure about that? I thought the CRC only applied when reading the audio from a CD. The error correction/concealment was to deal with mis-reads from the optical medium. Once past that stage there is no error correction in the transmission of digital audio. Scoping the serial data, L/R data clock and bit clocks will show only the 16 (or 24) bits of audio data are being transmitted without all the extra data needed for the error correction.

Shawn

Some guideline from Audiopraise on how to wire SPDIF from Vanity93 to SubD25 AES inputs ;

The SPDIF output from the Vanity93 is galvanicaly isolated (floating),
and there is no connection with the Oppo chassis. SPDIF center pin to
(+), SPDIF ground to (-) and Oppo chassis to SubD25 should work well.


Cheer !

IMO Canare stuff is superb. They go an excellent job of testing their products and providing those specs.

From edorr - "The custom DSD conversion is a lot better. I don't know how much difference the reclocking makes relative to the Oppo clocking, because in both scenarios the Vanity board reclocks. So bottom line for a SACD application the Vanity93 board will beats the JVB mod hands down because of better DSD conversion and potentially better clocking. For playing Blu Ray, I don't know but I suspect the reclocking willl give the Vanity board the edge as well. If the JVmod also reclocks (ask them!), there may be no difference."

I have installed the Vanity93 board into my Oppo 93 and using it as a transport into Bryston BDA - 1 . All I can say is that the sound from this Vanity93 Oppo/Bryston is in a class by itself - just a shade lower than my Playback Design MPS-5 . No little achievement judging the cost difference of the two .

Larry

Great to hear. Some questions:

Why are you doubling down on DACs? The MPS-5 has digital inputs, so why do you need the Bryston?

Have you tried the Oppo into the MPS-5? If so, how does playing a SACD in the Oppo converted to LPCM at 176/24 into the MPS-5 over S/PDIF compare to spinning the same SACD played in native DSD in the DSD. According to some the MPS-5 is the best DSD converter bar none, so this would be an interesting way to asses what is lost (if anything) doing DSD->LPCM conversion.

are planning to eventually use the Oppo in a multi channel application?

Edorr - I will give it a trial next week , Oppo into MPS-5 , also do some listening as you suggested , Oppo to LPCM compared to MPS-5 alone .

I did Oppo Vanity 93 into Bryston DAC because I didn't expect its performance to be so closed to MPS-5 although Bryston is also a Class A DAC by Sterephile . I was testing digital out from the Vanity board but on brief listening , the sound was so good that urged me to give the combo a serious listening and yes , it was that good . The difference might be just ffff & fffff . Of course the 5th f is difficult to grasp , but you will not know there is the 5th f if not comparing AB on real time . And you pay a fortune for the 5th f .

My Oppo is to be out to Trinnov MC . Not actually intended for Music .

Cheer !

Also try to hook up your MPS-5 to the digital out of the Trinnov. You could use the Oppo as your 2 channel soure into the Trinnov, apply DRC, and then run output digitally into your MPS-5. It is very conceivable the benefits of being able to apply Trinnov DRC on your 2 channel sources trumps any difference in sound quality between spinning disc in the MPS-5 and the Oppo. If this is the case, your best signal path for 2 channel would be Oppo -> Trinnov -> MPS-5. Worth trying....

I have recently become interested in active speakers, specifically those made by PMC (http://www.pmc-speakers.com/products/professional/active). PMC's active units will accept AES3 digital inputs up to 192kHz. Each speaker has on board DSP (which operates at 96kHz) where one can control volume, crossovers, EQ etc. As I understand it, the speakers can be linked together to allow system control from a single remote, much like a Meridian set-up.

Having a modded Oppo output 7.1 channels of high res digital into such a set-up would be ideal although, as discussed, there would be a mismatch between the output of the modded player and the AES3 inputs of the speakers to address.

Is there yet consensus on the best way to handle the connectivity with the S/PDIF to AES conversation, especially since these would be long runs to speakers?

For this application, you probably need proper impedance matching / s/pdif AES/EBU conversion. I would consider getting a z system z8 digital router. Additional benefit is you can switch an additional MCH digital input or multiple 2 channel inputs into our system. I used one of these myself.

Well do the speakers use BNC/phono or XLR connectors?

IF BNC/PHONO:
You might get away with running RG59 video cable directly to the speakers and using BNC to RCA adaptors as needed. If the cable driver in the modded Oppo is specification compliant, that should work well for hundreds of feet. USE RG59 VIDEO CABLE. It's cheap and the proper stuff. If you must use RG6 make sure it has a solid copper center conductor. Copper cladd steel is only usable for CATV or RF in the TV band. Impedance is critical here. Don't get caught up in the audiophile cable voodoo here. The proper cable is easy to get at low cost.

IF XLR:
You will need a minimum of a matching transformer/amplifier. The unit that Edorr suggested is a good choice. YOU MUST USE 110ohm AES CABLE! The lengths involved for typical speaker runs are beyond the cheats you can do a six foot lengths. Belden, Canare Gepco, and Mogami all make this stuff. You can probably buy audiophile AES cables but they will be very expensive due to the limited market and simply not worth it. The bulk cable is less than 50cents a foot and the connectors can be bought for a few dollars each. And XLR's are very easy to solder by a novice.

One more caveat. Aside form the electrical differences, AES and SPDIF have a minor protocol differences. These cann ot be corrected by transformers and simple distribution amplifiers. It usually doesn't matter and AES can be freely exchanged with SPDIF. But I have seen a few cases where it does not work.

The technical specifics are in the channel status bits. AES uses these for metadata. SPDIF can optionally use them for a copy protection flag. This was only ever implemented on some early Sony consumer DAT recorders in the 1990s. So it's basically obsolete yet once and a while some pro gear doesn't like what is put in that space on consumer gear.

Thanks for the replies.

From the user manual of one of the PMC's active models "The electronic-balanced analogue input and AES digital input accept 3-pin male XLR connectors, wired with pin-1 screen (ground), Pin-2 signal positive (hot), and pin-3 signal negative (cold)."


Edited by sierraalphahotel - 4/14/13 at 2:53pm

Unless you are limiting your system to a single source (modded Oppo), you will need some way to switch other sources into your system. With the Z8, you will have the option of routing 8 more channels digitally into your speakers.

What you could do is get an old Meridian 561 - this has no HDMI inputs of course, but it has 4 x S/PDIF out. So you can run legacy dolby sources (including satellite TV) into the Meridian and route them to your MCH active digital system. If you have any inputs left, you can also run a USB converter's S/PDIF output into the router for a 2 channel music server source. I used to do precisely that; route an Oppo, Meridian and USB converter through the Z8 (albeit into my Trinnov, not the speakers directly).

Alternatively, he could purchase a Datasat AP20 without Dirac Live. They have a version with 8 channels of digital inputs and outputs and another with 16 channels. However, this is a pro unit, since it is not geared toward consumers, so it may lack some niceties he may be accustomed to as a consumer (e.g there are no conventional connections in the back panel, he must use breakout cables). However, he should have no need for matching transformers.