vadym
Minor Hero
Posts: 13 
|
Post by vadym on Dec 5, 2013 12:49:13 GMT -5
Thank You.
DACs may say about ability pure DSD and Hi-res audio, s/n ratio ets. And of course the analog circuitry is no less and may be more importent
|
|
|
|
Post by repeetavx on Dec 5, 2013 13:04:38 GMT -5
I've scoured the net and haven't been able to find any documentation on the DACs used in the PT-7030 or its twin brother the Rotel RSP-1572.
Because the PT-7030 is the fraternal twin of the RSP-1572, I looked to see which DACs some of the other Rotel processors are using and found only one mention of one product. The Rotel RA-12 integrated amplifier uses the Wolfson WM8740 24 bit/192kHz DAC.
I guess one of us is going to have to pull the top off one of our units and see if we can identity which chips are the DACs.
|
|
|
|
Post by swampfire on Dec 5, 2013 13:05:16 GMT -5
Here's a great article explaining the difference between balanced, psuedo-balanced and unbalanced cables: www.atlascables.com/right-connection.html (skip to section 6.5, "Appropriate interconnects") It's very interesting that they recommend unbalanced (RCA) connections for analog line-out connections. That explains why you don't see XLR connectors on many expensive phono preamps (e.g. this one). Getting back to the PT-7030... I should be able to show that it is "truly balanced" if I can plug in a balanced 3-conductor XLR cable and confirm that: 1. None of the 3 pins are shorted to each other 2. One of the connectors is connected to ground (7030 chassis) 3. The other 2 connectors are using differential signalling (will need to borrow an O-scope for this) This will also be a good time to check the impedance of my $7 XLR cables. |
|
|
|
Post by repeetavx on Dec 5, 2013 13:07:49 GMT -5
I can prob sell my 40% card now too!! I'd hold on to it until you know whether or not you want the RMC-1 or not. Even though it is a couple of years away, that just means that it will have the newer technologies incorporated into it. |
|
vadym
Minor Hero
Posts: 13
|
Post by vadym on Dec 5, 2013 15:24:20 GMT -5
I've scoured the net and haven't been able to find any documentation on the DACs used in the PT-7030 or its twin brother the Rotel RSP-1572. Because the PT-7030 is the fraternal twin of the RSP-1572, I looked to see which DACs some of the other Rotel processors are using and found only one mention of one product. The Rotel RA-12 integrated amplifier uses the Wolfson WM8740 24 bit/192kHz DAC. I guess one of us is going to have to pull the top off one of our units and see if we can identity which chips are the DACs. Why dont we think they use DACs like in UMC - 200 or test DSD 1793 like in XMC-1 (it will be better)? If the PT-7030 is really the fraternal twin of the RSP-1572 then software from Rotel fit to PT 7030 and it will fix the problems in delay or miss 1-2 second at the beginiing of the tracks? |
|
|
|
Post by mgbpuff on Dec 5, 2013 15:32:52 GMT -5
Frankly a manufacturer who advertises balanced outputs and labels the outputs "balanced", ought to be sued if they are not indeed balanced. This constant questioning of whether or not it's "true balanced" or differentially balanced or simply balanced is only answerable by ripping one's unit apart and examining it in detail(I'm not about to do this), or the manufacturer simply answering the question fully. I am sure in my own mind that the PT-7030 has a balanced output scheme (two hot signals 180 degrees out of phase and a ground conductor) and not an unbalanced scheme (one hot signal and one tied to signal ground and a chassis ground). I don''t think Keith answered this question fully, but I don't think he was being coy either - he just needs to state that the PT-7030 XLR outputs are indeed balanced outputs. Another answer to this enigma and many other technical questions would be to make schematics available (even for a charge) to owners of the equipment like used to be the case years ago.
|
|
|
|
Post by repeetavx on Dec 5, 2013 17:05:36 GMT -5
Actually the RSP-1572 is notorious for having the same delay problems. As far as the software, the HDMI reports that it is Rotel HD AV and the blue tooth reports itself as Rotel.
|
|
|
|
Post by swampfire on Dec 5, 2013 19:01:21 GMT -5
Never mind....someone who has graduated as an Electrical Engineer more recently than 1987 will have to dig into this.  Getting back to the PT-7030... I should be able to show that it is "truly balanced" if I can plug in a balanced 3-conductor XLR cable and confirm that: 1. None of the 3 pins are shorted to each other 2. One of the connectors is connected to ground (7030 chassis) 3. The other 2 connectors are using differential signalling (will need to borrow an O-scope for this) This will also be a good time to check the impedance of my $7 XLR cables. |
|
|
|
Post by swampfire on Dec 5, 2013 20:43:33 GMT -5
Hi all, I've started posting "mini reviews" of the PT-7030 in the review section. I'll update this post with a link each time I add new one, so you can just bookmark this post. Here's what I have planned: #1 - Using the USB port with iDevices <click me>
#2 - Digital audio decoding
#3 - Everyday audio adjustments
#4 - Video
#5 - Front panel, remote and OSD
#5 - Calibrating with Room EQ Wizard
#6 - Audio qualityMy hope is to post one a week. I work with A/V in my career, so I know at least enough to be dangerous.  - Swampfire  |
|
|
|
Post by swampfire on Dec 5, 2013 21:04:48 GMT -5
If the PT-7030 is really the fraternal twin of the RSP-1572 then software from Rotel fit to PT 7030 and it will fix the problems in delay or miss 1-2 second at the beginning of the tracks?
I've played a CD, SACD and BluRay in both my Sony PS3 and my Panasonic DMP-BD35 (using HDMI 1). I've skipped tracks and chapters on all of them, and the audio change is instantaneous. Here's my firmware info: Controller: V1.00 Video: V1.01 Scaler: V1.00 Audio: V1.10
Can someone who has observed an "audio delay" please check your firmware versions against these? Thanks. |
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Dec 5, 2013 22:24:00 GMT -5
If the PT-7030 is really the fraternal twin of the RSP-1572 then software from Rotel fit to PT 7030 and it will fix the problems in delay or miss 1-2 second at the beginning of the tracks?
I've played a CD, SACD and BluRay in both my Sony PS3 and my Panasonic DMP-BD35 (using HDMI 1). I've skipped tracks and chapters on all of them, and the audio change is instantaneous. Here's my firmware info: Controller: V1.00 Video: V1.01 Scaler: V1.00 Audio: V1.10
Can someone who has observed an "audio delay" please check your firmware versions against these? Thanks I have the same versions but I experience delays with all digital sources (HDMI, Toslink, Coax) It happens with any source or input that I use...CD Player, Blu-ray, antenna, music streaming, etc. I am still waiting for the firmware that is supposed to fix this. |
|
|
|
Post by creimes on Dec 5, 2013 22:42:39 GMT -5
The $2-7 DAC chips matter far less than the supporting analog circuitry. This is the picture that ultimately sold me on the PT-7030.  Also...why so much angst over whether the outputs are truly balanced or not? Unless your amp is in another room, it won't make a bit of difference to the sound. I'll pop the lid this weekend and see if we can put this question to rest for good. Myself and others here with the 7030 find the analog stage very pleasing, I have my DC-1 connected to the reference input of the 7030 and it sounds amazing IMO. Chad |
|
|
|
Post by swampfire on Dec 6, 2013 0:04:44 GMT -5
It happens with any source or input that I use...CD Player, Blu-ray, antenna, music streaming, etc. I am still waiting for the firmware that is supposed to fix this. Can you describe exactly what you mean? Is it a lip synch problem, or 1-2 seconds with video and no audio? When I switch sources, I do get video 1-2 seconds before I hear audio. I don't consider this a problem, but I don't switch sources very much. Skipping chapters or tracks, I get no audio delay. So maybe this issue is source device dependent. Regards, John |
|
|
|
Post by swampfire on Dec 6, 2013 0:17:12 GMT -5
The Stealth DC-1 looks very nice. Have you compared a digital source via the DC-1 vs. just going directly through the 7030? Or is your upstream source Async USB, so you need the DC-1? I'm seriously considering the Oppo 103 with Darbee, to replace my PS3. I get tired of my son's friends sending chat requests when I'm watching a movie.  |
|
|
|
Post by novisnick on Dec 6, 2013 0:40:55 GMT -5
The Stealth DC-1 looks very nice. Have you compared a digital source via the DC-1 vs. just going directly through the 7030? Or is your upstream source Async USB, so you need the DC-1? I'm seriously considering the Oppo 103 with Darbee, to replace my PS3. I get tired of my son's friends sending chat requests when I'm watching a movie. I enjoy my Oppo very much, there was no offer of Darbee when I purchased. If they had I would have sprung for it. Nice piece of gear.IMHO Nick |
|
|
|
Post by intgenx on Dec 6, 2013 2:17:20 GMT -5
The one function that is most important to me in a processor is the DAC function (S/N ratio, THD, sampling, clock, jitter) ... and that includes the DAC chip and its analog circuitry with balanced output ... rest of the processor is just "additional weight" that just ends-up costing me more in shipping and customs duties ...
For those who say "balanced does not matter unless its a long cable run"... please... we all know that... but I need to do justice to the professional studio Active monitors (Neumann KH310 with 270W total built-in amp) for all 5 channels that I have... and that can be done only by connecting them to a balanced source (as best a balanced as I could find in my budget without going to the ultra-high-end gear)...
the DAC and balanced output is the only thing I care about... and Emotiva's silence so far and no upfront information in the brochure or website to begin with is quite perplexing
|
|
|
|
Post by cwt on Dec 6, 2013 5:40:20 GMT -5
I don''t think Keith answered this question fully, but I don't think he was being coy either - he just needs to state that the PT-7030 XLR outputs are indeed balanced outputs. Another answer to this enigma and many other technical questions would be to make schematics available (even for a charge) to owners of the equipment like used to be the case years ago. +1 I would be very surprised if its not considering the original price for the old 'dealership' model was $2500us not 1700 direct and this was the only reference I found for the balanced outs vvv ; good enough short of dismantling for me  If its good enough for Big Dan to put in his ht who was the pres of the company when it was designed ;nuff said  As swampfire said good dacs these days have s/n ratios and dynamic ranges superior to the human ear ;its the analog stages afterwards that matter and the 7030's are ++ www.avguide.com/article/sherbourn-technologies-introduces-the-pt-7030-71-channel-home-theater-preampprocessor |
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Dec 6, 2013 6:25:43 GMT -5
It happens with any source or input that I use...CD Player, Blu-ray, antenna, music streaming, etc. I am still waiting for the firmware that is supposed to fix this. Can you describe exactly what you mean? Is it a lip synch problem, or 1-2 seconds with video and no audio? For example...when streaming music (toslink), there is a delay between each track so you miss the first 1-2 seconds of the next one. It also does this when using my CD player (coax) and I will also have an audio delay if I pause, skip forward, etc when watching a blu-ray or streaming video. This is not source dependent as I have it happen with 4 different sources. It does this with any digital input whether it is HDMI, Toslink, and Coax. |
|
|
|
Post by creimes on Dec 6, 2013 8:51:09 GMT -5
The Stealth DC-1 looks very nice. Have you compared a digital source via the DC-1 vs. just going directly through the 7030? Or is your upstream source Async USB, so you need the DC-1? I'm seriously considering the Oppo 103 with Darbee, to replace my PS3. I get tired of my son's friends sending chat requests when I'm watching a movie. The 7030 sounds great as well, sometimes I think I can tell a difference and other times I can't, I don't really a/b stuff too much and get all crazy about the sound of this or that as I like to just enjoy the music and i do hae my Mac Mini connected with USB to the DC-1, really that's all I use it for and have been contemplating keeping the DC-1 just for that...?, I was thinking of grabbing some airmotiv 4's for a second setup but space is limited in my house for that and I see the airmotiv lines is totally sold out now. Chad |
|
|
|
Post by intgenx on Dec 6, 2013 13:37:45 GMT -5
Just got a reply from Emotiva - confirming that the DAC is Burrbrown and that the XLR output is "not fully balanced"...
Can someone confirm what kind of pseudo or partial balancing are we talking about here?
In any case - I'm not really sure if there are any products in this price category that are fully balanced...
Are the Onkyo PR-SC5508, PR-SC5509 or Marantz AV7005 or AV7701 fully balanced?
|
|
If its good enough for Big Dan to put in his ht who was the pres of the company when it was designed ;nuff said 
As swampfire said good dacs these days have s/n ratios and dynamic ranges superior to the human ear ;its the analog stages afterwards that matter and the 7030's are ++ 