So is the balanced output on this amp actually balanced, single ended but just 4 pins or some other abomination? I am confused by some of the statements.
AndrewMason139Follow
THX Ltd. Analog & Power Engineering Expert
2D
MadMan007@MadMan007 There are some very expensive, very nice opamps in there! Supporting truly balanced signal pathway throughout would shoot the cost through the roof, for negligible improvement. See Bruno Putzeys' EDN article on why having truly balanced signal path isn't necessary. "Symmetry is useless". " Differential transmission of audio doesn't mean you need to make a symmetrical voltage " https://www.edn.com/design/consumer/4429968/2/The-G-word--How-to-get-your-audio-off-the-ground
Then in another post claims its balanced when compared to the Monoprice 788? So which is it balanced or not? I dont think you can have it both ways its either balanced throughout or its not balanced.
AndrewMason139Follow
THX Ltd. Analog & Power Engineering Expert
3D
joshy_bennettHi @joshy_bennett . Compared to the Massdrop 789, the Monoprice 788:
-uses the same AAA technology
-788 has less output current/voltage/power
-788 no true balanced output (has XLR-4, but it's only driven single-ended)
-788 includes a DAC selected by the Monoprice team.
So it depends on what you're looking for.
AnentThe question arises because an engineer from THX referenced the Monoprice 788 as NOT having REAL balanced output (r+, r-, l+, l- conductors) but a single-ended output with merely an xlr4 connector.
Everything on this drop suggests the 789 is balanced. The engineer mentioned phase inversion vs discrete DAC's per channel, there's a difference in power output etc. But, the 789 was supposed to be a tweaked 788, or at least that some people's impression. The differences just need some clarification.
AnentI saw your previous post about the “$2995 888 amp”. There isn’t actually any 888 amp on the market right now. 888 and 789 has similar output power of maximum 6W suitable for a high power headphones amp. The Benchmark AHB2 not only came out a few years earlier than these designs. It is a speaker amp with maximum 480W in bridged mono mode.
AnentKizer's are one of the few I haven't gotten yet. There are a few designs that tickle me, but I have very particular tastes... :)
There's just a lot about this drop that simultaneously impress me, and give me pause. I'm gonna have to think on it a bit longer.
LuckyEightsBottom line: The output of this 789 is balanced (XLR-4) and unbalanced (3.5mm or 1/4"). And the inputs can be balanced (XLR-3's) or unbalanced (RCA).
Errata: The signal path internally is fully differential throughout (per Putzeys), but is NOT truly balanced in a few sections. We preserve the full signal integrity but we avoid increasing the retail price for no measurable benefit.
SqueeI inquired to Monoprice regarding their upcoming THX AAA 788 DAC/amp's 4-pin XLR output. Hobie S. from their staff promptly confirmed that it is, in fact, "fully balanced".
With that good news (and the fact that the unit has a DAC with a full array of digital inputs... and Dirac Sensaround processing on-board), Monoprice's 788 is looking quite promising. Shame they keep pushing the release date back, though.
SqueeI would think that the Monoprice 788's xlr4-out has to be 'balanced' to be compatible with balanced cables connected to it.
I followed-up my original question by asking if the circuitry from the amplifier to the output was fully balanced (differential). Unfortunately, Monoprice chose to delete my questions from the page. I was looking forward to this upcoming Monoprice DAC/amp, but this kind of behavior doesn't sit well with me.
LuckyEightsDepends on what you mean by balanced.
By balanced do you mean two channels out of phase? Then it's balanced. Do you mean taking balanced in and running everything through the amp balanced? No. They phase invert the signal in the amp to create the balanced signal.
That's in contrast to the 788 from monoprice which isn't even running phase inversion. It's supposedly a standard, single ended output with a 4pim xlr connector.
AndrewMason139Follow THX Ltd. Analog & Power Engineering Expert 2D MadMan007@MadMan007 There are some very expensive, very nice opamps in there! Supporting truly balanced signal pathway throughout would shoot the cost through the roof, for negligible improvement. See Bruno Putzeys' EDN article on why having truly balanced signal path isn't necessary. "Symmetry is useless". " Differential transmission of audio doesn't mean you need to make a symmetrical voltage " https://www.edn.com/design/consumer/4429968/2/The-G-word--How-to-get-your-audio-off-the-ground
Then in another post claims its balanced when compared to the Monoprice 788? So which is it balanced or not? I dont think you can have it both ways its either balanced throughout or its not balanced.
AndrewMason139Follow THX Ltd. Analog & Power Engineering Expert 3D joshy_bennettHi @joshy_bennett . Compared to the Massdrop 789, the Monoprice 788: -uses the same AAA technology -788 has less output current/voltage/power -788 no true balanced output (has XLR-4, but it's only driven single-ended) -788 includes a DAC selected by the Monoprice team. So it depends on what you're looking for.