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Nice answer there JesseG 😉
In laymans terms, when running a simple audio cable from a soundcard to a transmitter, the impedence is of little or no consequence, Just make up the correct lead and plug it in.
Your TX will most likely have a 75ohm BNC connector on it, so one of those (if you cant get a 75, a 50 will do) and your Trace Marian Alpha card will have a 6.25mm jack plug. use some reasonable grade shielded cable inbetween any you are ready to go.Yorkie.
Hi Gavin, if as you said, you are transmitting only in Mono (I assume with RDS?) you only use 20hz-16Khz of your soundcard’s frequency spectrum for your audio and a small notch at 57Khz. Any soundcard which is 192Khz capable should be pretty much close to perfect this low down in the spectrum maybe rolling off after 40-50khz but not usually earlier than that. If you have an HF rolloff which is giving you a low RDS level, just increase the RDS level a bit, much less of a headache than messing with PEQ. For mono, I really can’t understand why you’d need PEQ unless you have a REALLY poor soundcard. Even your Audigy 2ZS (how do I know that??!!) should be fine up to 20khz.
If you were running stereo of course this would be different, you do need close to perfect linear response curve up to 60khz, but for mono, as long as you are linear to 16khz, your audio is not affected, then even if you have a large drop, like say 12dB up at 57Khz, then just increase the RDS level by 12dB.
Tilt on the other hand is important to have correct, mono or stereo, RDS or no RDS. BBP is the only program to offer this feature.
Stvgr, that’s right, the Marian Trace Alpha card does not need the Tilt to be calibrated or adjusted. It is 100% DC straight. Any other card does require tilt calibration.
Yorkie.
Camclone, I think we kinda got away from the fact that what we were waiting on here was a functioning prototype and not necessarily a polished product, the intention was initially to test the basic technology and see how it went, this feedback would have then helped Stelios figure out improvements/modifications.
Somewhere along the line, this has got blown up into a full R&D project and now the "prototypes" are getting closer to a final product. Of course, the better the product the better for everyone but I think that we have to expect imperfections and that we are effectively beta testers.Yorkie.
The settings on these cards will vary from card to card due to component value tolerances, especially in the case of modded cards.
Also the TX needs to be connected in parallel and switched on to make the tilt calibration valid.
Simply copying someone elses reading will not work.Yorkie.
I havent had a Juli@ yet but the similar components are used on the output of a Maya, which I have done several of, the tilt on these is usually 3.
Remeber however that the tilt from one Juli@ may not be the same as the tilt on another supposedly identical one, there are tolerances in component values and these can make a difference. Also remember that when measuring the tilt, it should be done with the transmitter connected in parallel, this can make a huge difference, I have had one computer (with an onboard ALC888s codec) on 3 different transmitters and the tilt values ranged from 24 to 47 depending upon which TX was connected.
Having someone else measure the tilt on a soundcard is no use, yoou need to set it up on your own card and with your own TX connected (and powered up) otherwise, the measurement is void.
If a scope is not possible, the BBCal tool is a good alternative and just requires $2 worth of parts to work and any (even a 48khz) soundcard to calibrate the tilt. You however cannot make spectral linearity checks by this method as the spectral linearity of the card being used for the measurements would be unknown itself.Hope this helps.
Yorkie.
[quote author=”sigmacom”][quote author=”Leif”][quote author=”Boki”]Question is,
Does Leif wants to make such STL software?[/quote]Having this exciter in my possession will certainly increase motivation and thus scheduling priority 🙂.[/quote]
OK, I got the allusion… 😆[/quote]No pressure Stelios…LOL 🙄
Unfortunately, here in the UK, the typical business broadband speed is 8128/832kbps some providers offer up to 20mb download and 2.5 upload in certain areas but only a small minority acheive anywhere near this. Even those who acheive good speeds often suffer slowdowns in the evening and often heavy traffic manangement. In the current landscape it would be highly unlikely to be able to sustain a constant high bitrate upload/download link. Often it’s hard to even get a reliable 128k webstream.
Over the next few years the next generation of broadband is being rolled out, with speeds up to 40mbps download, dont know yet what the upload speeds will be, maybe then things will improve, for me though, most of my STLs for this purpose will be via LAN/WLAN so bandwidth is not really an issue.
I played the Bjork sample of this to a few clients and they were blown away by it, now they all want to know, when does the update come out with this on it. I might even chance upgrading some to a beta versions as I usually don’t upgrade unless there is a new stable release. This preset just might make me change my ways.
[quote author=”sigmacom”]
Buffer size is not a big issue for me, but SFN over internet scares me a bit…
Anyway, it will be a very interesting experiment. 🙂[/quote]A very interesting experiment indeed, when I was discussing with Leif how we might like a Digital MPX STL to work (this seems like ages ago..), I did conceed the point that MPX over the internet might be a little optimistic but I’m certainly hoping to be able to use it over LAN and WLAN networks such as 5.8Ghz TCP/IP links. This now will be all the more of a sweet idea if an SFN will work over this too although I guess some extra functionality/compatability may have to be included in any future IP/STL to allow the extra SFN info to be passed.
Fun times ahead I can predict.From the Harris Brochure..
"A single stage upconverter mixes the output of the digital modulator with a synthesized local oscillator, producing the on-channel FM carrier".
Sigmacom’s DDS exciter does not create an intermediate frequency which is upconverted, it generates the required carrier frequency directly, so where the Harris TX will create the carrier/modulation at approx 5mhz, then upconvert it to say 100Mhz, the Sigmacom makes the carrier on 100mhz in the first place, no upconversion. This is a much better way to do it as mixing creates harmonics which need to be filtered, no mixing, no harmonics. Filtering will also distort the wanted signal.The Nautel brochure does seem to suggest this does direct carrier synthesis which is similar to the Sigmacom method but what Sigmacom’s unit offers, and the thing that has got all us BBP users excited is it’s ability to take an MPX signal digitally, either via optical or coaxial. No other exciter yet can do this.
Both the Harris and the Nautel can take in audio as L/R digitally (which would normally have gone through a processor) and then use an onboard stereo encoder and an outboard RDS coder to give the final MPX signal but this will be vastly inferior to the audio being processed, encoded into stereo AND having the RDS digitally injected by BBP, then the resulting MPX being inserted to the exciter digitally and this digital signal being directly modulated, digitally onto the direct to frequency carrier which itself is created, you guessed it, DIGITALLY…
Do not underestimate how big of a leap forward this is, this is as clean and as close to perfect an FM broadcast will ever get, and most likely there will never be a tuner good enough to fully exploit how good of a signal is being transmitted.George, I totally concur with JesseG, Dancing girls would be great, if they could also be holding drinking beer as per Joop’s idea or Jagermeister also, this would truly be a visual treat.
For the technical test, I think it’s just really a case of testing all of the input modes, if remember correctly these are:
1. Analog L/R input using built in DSP coder.
2. Digital optical L/R input using build in DSP coder.
3. Digital electrical L/R input using built in DSP coder.
4. Analog MPX input.
5. Digital optical MPX input.
6. Digital electrical MPX input.Most of our interest lies primarily with 5 and 6 as these are where the quantum leap in quality can be gained with a fully digital airchain and BBP providing a digital MPX straight to the DDS carrier.
Yorkie.
Q106, to obtain a Marian Trace Alpha, it depends where in the world you are, there is a list of dealers for this card on Marian’s website,
http://www.marian.de/en/shop/international
otherwise, try your local google and see if it can find local sellers for you or find a local pro-audio stockist who is a Marian dealer as they may be able to order one for you. If all else fails, contact Marian direct via the website above as I am sure if you cannot find a dealer locally, they will sell and ship you one.
The Juli@ card (I also have good results using the Maya44PCI) would be a good second choice if you cannot get a Marian but the Juli@ will require tilt calibration whereas the Trace Alpha does not.Hope this helps,
Yorkie.
Stelios, A Juli@ gives 192Khz out on the electrical output, did you test this?
Which card do you intend to use for the optical DMPX test?Yorkie.
"Also currently in development are additional tools to measure quantifiable processing elements like: fatigue, distortion, quality, clipper depth and power in each processing band, along with utilitarian functions to log preset history, and detailed system diagnostics."
Is this one of your projects Leif? or is this Omnia’s own?
This sounds like a very interesting tool if it can be purchased standalone.Yorkie.
