5.1+ Processors with Best DACs/Preamps?
For the 5.3 system I want to build, my plan was to have JRiver feed Blu Ray disc audio to this MCH DAC via USB. https://www.oktoresearch.com/dac8pro.htm https://www.stereophile.com/content/okto-research-dac8-pro-da-processor
But like most DACs, the Okto’s balanced outputs only deliver ~ 4.1 volts, which KR found insufficient to drive his power amps (Benchmark AHB2, NAD C298) with DIRAC Live 3 enabled. Thus, all balanced outputs of this processor would need to supply a minimum of 10 volts/channel to offset DIRAC gain losses of almost 20db https://www.sowter.co.uk/decibels.php , as KR mentioned in his review of the Topping Pre90. https://www.stereophile.com/content/topping-pre90-line-preamplifier
Unfortunately, there are no 8-channel preamps available, either from audiophile or pro audio brands. KR's fix was to buy three Topping preamps, which as shown in Fig. 3 its balanced outputs deliver very low distortion, and which virtually continues decreasing well beyond 10 volts.
https://www.stereophile.com/content/topping-pre90-line-preamplifier-measurements
But stacking three Pre90 preamps doesn't seem the most elegant solution, and KR mentioned that struggling with the Pre90's crappy remote is no fun.
So unless I find a reputable builder to affordably custom design a MCH preamp, the only alternative would be a MCH processor with a DAC section at least as good, but ideally far better than the Okto, and with all balanced outputs delivering at least 10 or 12 volts/channel.
If yes, how likely could its own master volume/mute remote control allow reducing all balanced outputs to ~ 5 volts or less without any loss of resolution and perceptible dynamic range?
If yes, which model (s) would also have a pair of high quality potentiometers for selectively setting levels of the front and rear/side speakers-like the ones John Curl used for designing the JC-2 preamp https://www.partsconnexion.com/tkd-potentiomters.html , which JA raved about going head to head against his Levinson 380S? https://www.stereophile.com/solidpreamps/308para/index.html See p. 10-11. https://parasound.com/pdfs/JC2Manual.pdf
Theta Digital are the only MCH processors I’m aware of which might have DAC sections at least equaling the Okto DAC 8 Pro, though I doubt its preamp performance would match that of the Parasound JC-2.
Please suggest brands/models.
Ideally, such processors would also be customizable, allowing omission of video and unbalanced connectivity, thereby minimizing final cost.
The Lyngdorf MP-40 or MP-60 are worth looking into, and they have excellent, proprietary room correction that harkens back to the days of TacT. Here are links to their website and a feature comparison chart just fyi… https://lyngdorf.steinwaylyngdorf.com/electronics/ Best of luck. |
I have the solution but it's not very elegant. Buy a Theta Casablanca 3, regular not the HD, and two Six Shooters. The Six Shooter was reviewed in the Absolute Sound issue 158. It will compare to analog preamps in the 5k-10k range. You can run 2 for 12 channels of analog volume control with 3 inputs, two balanced and one single ended. Jim White of Aesthetix Audio, a former Theta engineer, designed the volume controls from which it's based. When I owned them, I compared them to several analog preamps at the time. I believe you could find all three components for 2k. Really you are only using the CB3 to control the Six Shooters as it will only decode DD. You will not be disappointed with the sound quality. They will have the voltage output you need for Dirac. If you use good dacs, in the method you mentioned, no prepro will be able to match the sound quality. But again, it's anything but an elegant solution. I have 4 Theta Gen 8s3 dacs that I use. The best multi-channel device I have found to feed them is the Audiopraise Vanitypro. I run Roon and Dirac live with this set-up. I wouldn't use any prepro on the market for music, they all fall short.
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Anyway, about Theta Digital options, for a 5.3 system I would think that the most of I would need would be 8 channels, not 12. But why the need for that six shooter preamp when this seems to have all needed outputs to front, center and rear amps and at least two subwoofer channel outputs?
Does this Casablanca 3 have Class A and 20 volts max on all outputs? Is it possible to buy refurbished models from Theta Digital, minus the stuff I don’t need, like the unbalanced I/O, upgrade the DACs all for ~ $6500?. FWIW, besides the Exasound s88 and the Okto DAC 8 Pro, there’s https://www.stereophile.com/content/benchmark-dac3-hgc-da-preamplifier-headphone-amplifier#comment-611678 and the arguably better sounding https://www.stereophile.com/content/bryston-bda-3-da-processor And this earlier model, also with class A output stage.https://www.theabsolutesound.com/articles/bryston-bda-2-digital-to-analog-converter/ But the DAC3B has no remote to control its output well above 10 volts , while the Bryston DACs’ balanced outputs max out at 4 volts. In other case, I’d need three of either, plus a MCH preamp for the Brystons. In any case, there’s another problem: While many today choose to stream content, I play lots of 1080p BDs and DVDs, and much prefer using these Windows players. https://jriver.com/ https://www.cyberlink.com/products/powerdvd-ultra/features_en_US.html?r=1 https://www.videolan.org/ They decode DTS-MA to a lossless MCH PCM signal, play all region discs and have the zoom and slow motion features which I often enjoy using, but which are found in practically no hard wired BD players. Thus, my pc would need to output the video via HDMI, either to the processor or directly to my TV. But as neither SPDIF nor AES/EBU can transmit lossless MCH audio, the processor would need to have a USB audio input to do so, to be fed from my pc, like this DAC has. https://exasound.com/Products/s88StreamingDAC.aspx But regardless of brand, design or price it seems that few if any MCH processors have a USB audio input. https://bryston.com/preamps/sp3/ https://www.audiocontrol.com/home-audio/immersive-av-preamp-processors/maestro-x7/ https://www.mcintoshlabs.com/products/home-theater-processors/MX100 https://nadelectronics.com/product/m17-v2i-surround-sound-preamp-processor/ And even if they did, could perfect syncing and quality of the video and PCM 5.1 audio from the Blu-Ray disk be assured, when played via any of these three Windows players?
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And all with other comments about the DAC3B here https://goldensound.audio/2022/04/06/benchmark-dac3-b-review-good-ish/ and especially to DACs here https://forums.stevehoffman.tv/threads/dacs-recommendations-for-3d-soundstage.1077916/ how might the size and proportions of the Casablanca DAC’s soundstage compare with the Brystons?
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@ajant The Six Shooter was a bridge for Theta to create an analog bypass because the Casablanca didn't have one. Yes, 20 Vrms balanced Class A on all their stuff. No refurbished stuff. Look, I know this suggestion is "far out there." It's just one of those, "judge the method by the result," kind of things. The route I described is likely the cheapest route to the best sound. It is also the most non-elegant solution. The route you are pursuing with an analog 8 channel preamp will yield the best results. I haven't heard the latest Bryston dacs. Bryston makes great stuff. Theta was just always more natural sounding and Bryston was a level lower. I don't know if that's still the case. I think the dac section doesn't have nearly as much of an impact as the analog output. Jim White, of Asesthix Audio designed the analog outputs of a lot of the Theta gear. Use the "at" symbol and the members name. A list will come up, you select that and you can quote. |
@ajant I find the review of the Benchmark DEAD ON. That's excactly what I observed. |
