It appears you are right. The mono amp provides an industry recognised XLR socket for its balanced input, but on further investigation it appears that the stereo PA5 uses an unconventional socket for a stereo jack plug to take a balanced signal. How very odd and I wonder why! The back panel of the PA5 simply labels the inputs as IN1 and IN2 with no indication of their type.
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Why use monoblocks?
- Thread starter JustAnAudioLover
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Then you must really dislike the R2R deck. If so, we are not going to be friends!
The R2R is just a little cooler than a nice turntable and takes more space. Bet it gets used about as much as my turntable!
TRS isn’t uncommon in pro audio. Also, the footprint is smaller so it suits better with small boxes. The manual of the amp certainly will hold information on the ports.
Most power amps will do the same.Many believe in 'separates'... for many a reason.
These are just fringe groups who take 'separates' to another level.
Looked at it from a different perspective: Monoblocks prevent a single point failure.
If one of the monoblocks DOA; at least, you can still listen to music in the other mono channel.
xanalog
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There may not be twice as many single-point-failure modes with a stereo power amp (re: 2x monoblocks) but the commonality of the power supply (in a stereo single-box) will render both channels DOA.
I was trying to oust a reason for owning two of the same and that was the only justification (for mono listening) deemed viable (imo).
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Sure do listen in a room. What I am suggesting can be easily measured on both counts, regardless of your opinion. Damping factor also depends on amp output resistance and resistance of load, which includes resistance of wire. With monoblock wire length therefore resistance can be minimized with thick and ultra short speaker cable as the amps can be placed directly next to speakers. Remove passive crossover to maximize it.
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A bit unlikely, but poor PSU recovery after a significant impulse in one channel, may be a measurable benefit.
If both amplifier boards share a common PSU and the PSU is not particularly stiff, a significant impulse on, say the left channel will drain the PSU and there will be a period of instability followed by recovery. This will also affect the right channel even though it did not experience a significant impulse. In a monoblock approach this won't happen. The effect can be ameliorated by ensuring a stereo amplifier has a sufficiently robust PSU with good recovery characteristics.
Unfortunately, amplifier recovery after an impulse is no longer routinely measured. I wish it was.
If both amplifier boards share a common PSU and the PSU is not particularly stiff, a significant impulse on, say the left channel will drain the PSU and there will be a period of instability followed by recovery. This will also affect the right channel even though it did not experience a significant impulse. In a monoblock approach this won't happen. The effect can be ameliorated by ensuring a stereo amplifier has a sufficiently robust PSU with good recovery characteristics.
Unfortunately, amplifier recovery after an impulse is no longer routinely measured. I wish it was.
What Im saying is those effects are so small youll never hear the difference. Lets see those easily measured differences in damping factor.
A terrible crosstalk in stereo amps is -40db at 10k, -60db at 1khz. add a few room reflections and theres no way that level of cross talk is audible.
I though we were talking about amplifier, not system damping factor. So you think you can hear the difference between 2' of speaker wire and 10'? That will need proof. If you want to take into account the speaker and cable: 20' (10' with return) of 14awg cable has a resistance of .05 ohms. Most speakers dont go below 4 ohms. so the difference in damping factor, going from 10' to 0', is 1.25%. Inaudible.
If you consider that damping is most important at the speakers resonant frequency, where the impedance is the highest, say 16ohms the difference is now only .3%.
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MattHooper
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Many years ago, I switched from a Conrad Johnson 45 W stereo tube amplifier to my Conrad Johnson premiere 12 tube mono blocks (140w).
I don’t have any magical beliefs that mono blocks offer better sound “ just because they are mono blocks.”
But at the time this was the way for me to get more tube power, which paid off in my systems.
I don’t have any magical beliefs that mono blocks offer better sound “ just because they are mono blocks.”
But at the time this was the way for me to get more tube power, which paid off in my systems.
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Oh dear....
how did it pay off
I'd hate to pin myself in with a mono block that can only ever be a mono block. But I like that the benchmark ahb2 can be ran as a mono block and make a ton more power than running it in stereo, if I ever need to upgrade. Even with low sensitivity speakers I haven't ever felt close to needing to double up though.
Count Arthur
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3.111... x MORE POWER!
I split the distance difference to my surrounds (5.1) with a pair of little ones, purely for my viewing pleasure. The wife digs ‘em too so that’s a bonus.
congrats for nothing
I like what an amp designer by name of Douglas Self said about monoblocks:
"There is no need to go to the expense of monobloc power amplifiers in order to keep crosstalk under control even when making it substantially better than the -20dB that is actually necessary. The techniques are conventional; the last stereo power amplifier I designed managed an easy -90dB at 10kHz without anything other than the usual precautions in this area. Dedicated followers of fashion pay dearly for the privilege as the cost of the mechanical parts will be nearly doubled."
"There is no need to go to the expense of monobloc power amplifiers in order to keep crosstalk under control even when making it substantially better than the -20dB that is actually necessary. The techniques are conventional; the last stereo power amplifier I designed managed an easy -90dB at 10kHz without anything other than the usual precautions in this area. Dedicated followers of fashion pay dearly for the privilege as the cost of the mechanical parts will be nearly doubled."
Because we can.Hi there!
I have what may be a silly question, but I'm genuinely curious.
Let's say you have want to have 100W for each of your two speakers. You could use:
* Topping PA5 II: 2x 100W
* 2x Topping B100: 2x (100W each)
In the end, you get roughly the same amount of power (based on these products' specifications). But the PA5 II route will get you there with a single device for ~$180, while the B100 route will need you to handle two devices, and for an amount of ~$600.
My question is: why use monoblocks at all?
It's inconvenient (two devices instead of one) and more expensive (at least in this example). Even if you want to power more than 2 channels, you could just buy multiple PA5 II and get more output power in mono mode than each B100.
I'm sure there's a very good reason for these monoblocks to exist, but I can't figure it out.
Could someone enlighten me? Thanks
I use bridged mono's on my subs (at 4 Ohms) and bridged mono's on each of my main speakers.
Why? because otherwise some amps would not be in use.
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