Must remember to include the words 'or a test measurement error'
This happens a lot with the ACA and connection of test equipment.
Enjoy.
Wait a sec. The 2V RMS is 6 volts peak-peak. But CD tracks and sources are recorded at the most -10dB ; -15 dB might be more common from older tracks. So then you quickly arrive at the old standard of .7 V RMS . . .
So yes, agree a pre-amp is nice to have
I just took delivery of a Schitt Asgard with the Multibit DAC. This replaces the Rotel integrated amp I was using as a preamp for the ACA (for my computer audio system).
With the Rotel, I had the volume 1/2 to 2/3 of the way up for what was nearfield background levels. It sounded good, but it just seemed a little off (a bit lethargic). The ACA sounded great when driven by my bigger, meaner preamp in my main system.
Connect the Schitt, flip to the high-gain setting, and BOOM. Everything seems to have 'clicked' in terms of the Schitt sending some serious output to the ACA and them pairing well. Maybe I am just imaging it, but seeing how the common consensus (and likely engineering one as well?) is the ACA likes a very powerful preamp.
Also, the two generally match in terms of size and general design, so two nice pieces of sculpture sitting on my desk.
I mentioned this earlier, but the ACA FINALLY got me what I wanted...which was absolute ZERO background noise or hiss. And now with this preamp/DAC, I feel pretty good about this system. Now about speakers!
Schiit Audio: Audio Products Designed and Built in California
With the Rotel, I had the volume 1/2 to 2/3 of the way up for what was nearfield background levels. It sounded good, but it just seemed a little off (a bit lethargic). The ACA sounded great when driven by my bigger, meaner preamp in my main system.
Connect the Schitt, flip to the high-gain setting, and BOOM. Everything seems to have 'clicked' in terms of the Schitt sending some serious output to the ACA and them pairing well. Maybe I am just imaging it, but seeing how the common consensus (and likely engineering one as well?) is the ACA likes a very powerful preamp.
Also, the two generally match in terms of size and general design, so two nice pieces of sculpture sitting on my desk.
I mentioned this earlier, but the ACA FINALLY got me what I wanted...which was absolute ZERO background noise or hiss. And now with this preamp/DAC, I feel pretty good about this system. Now about speakers!
Schiit Audio: Audio Products Designed and Built in California
Well, that is something I also noticed. I have a luxman pre from the early 80's (that probally need maintenance) and it's flaws are very visible with the ACA, in that meaning i removed it from the chain because it disturbed me. I run it from a passive preamp for the moment. I need an extra gainstage for my phono pre (low outpot), but i'm working on that.
Very interesting revaluation for me concerning the difference between the ACA run in stereo vs. balanced mode. My friend Stan and I were listening to Sheffield Labs Thelma Houston & Pressure Cooker (Vinyl), playing the first side in stereo, then re-listening in balanced. I've stated before that I prefer stereo mode (still do), he CLEARLY prefers balanced mode. His preference is the more forward staging and the crisp sound of the brass instruments. We also swapped back and forth again listening to Nancy Wilson (streamer) and Stan prefers the "live" sound he hears in balance mode. This shouldn't have surprised me because I've heard that some prefer H3 dominant to H2 dominant...but it did.
Oh absolutely,
Kind of depends on what you mean by balanced mode. With actual Balanced Inputs on a monoblock amp, sound will be more towards H3, ie more like the F-5, This should give a more ‘precision” sound,
The Bridged monoblocks should have more H2 than the above Balanced Input mode but maybe less than the single chassis stereo amps
The Parallel monoblocks probably leaning towards H2 also, and probably the most similar to the stereo single chassis. They should work especially well on 4ohm speakers or speakers that have big impedance dips.
You can see that there are so many parameters that we suggest you try ‘em all as there is no way to tell what you and/or your speakers will like best. This is a good thing!
Kind of depends on what you mean by balanced mode. With actual Balanced Inputs on a monoblock amp, sound will be more towards H3, ie more like the F-5, This should give a more ‘precision” sound,
The Bridged monoblocks should have more H2 than the above Balanced Input mode but maybe less than the single chassis stereo amps
The Parallel monoblocks probably leaning towards H2 also, and probably the most similar to the stereo single chassis. They should work especially well on 4ohm speakers or speakers that have big impedance dips.
You can see that there are so many parameters that we suggest you try ‘em all as there is no way to tell what you and/or your speakers will like best. This is a good thing!
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Bridged vs parallel vs speakers impedance-phase curves
Hi all, i am trying to learn the best choice for these speakers. Initially thought the nomex, with double woofer and nominal 4ohm impedance, would have preferred the paralleled aca, but.... Look please at the bass control area 30-90hz...it shows much higher impedance than 4ohms. To cut a long story short, will i leave my ear decide, or if i use aca bridged for more power it will bring the amp in difficult zone driving those? Thanxs
Hi all, i am trying to learn the best choice for these speakers. Initially thought the nomex, with double woofer and nominal 4ohm impedance, would have preferred the paralleled aca, but.... Look please at the bass control area 30-90hz...it shows much higher impedance than 4ohms. To cut a long story short, will i leave my ear decide, or if i use aca bridged for more power it will bring the amp in difficult zone driving those? Thanxs
your photo shows that your speakers are either ported, or TL, or Voigt.
those two peaks show that.
your speaker is tuned to around 40 Hz.
ignore the two peaks, the minimum impedance is the valley after the second peak, and it is within norm.
the rest of the impedance looks very smooth and would not be a problem for ACA in parallel.
those two peaks show that.
your speaker is tuned to around 40 Hz.
ignore the two peaks, the minimum impedance is the valley after the second peak, and it is within norm.
the rest of the impedance looks very smooth and would not be a problem for ACA in parallel.
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OK, Troels Nomex, vented 2.5 way.
He says nom. impedance 4 ohm, min. 3.2.
ACA in parallel mode will drive them fine, in bridged mode will have difficulty.
You either use ACA parallel or look for a different Pass amp, like M2, F4, F5 and some of the Alephs.
Another way is to convert your speakers to 3way, but that might not be that easy.
The best option IMHO is parallel ACA which means building one more ACA amp, and running them in parallel mode as mono blocks.
I can assure you the sound will be magnificent.
He says nom. impedance 4 ohm, min. 3.2.
ACA in parallel mode will drive them fine, in bridged mode will have difficulty.
You either use ACA parallel or look for a different Pass amp, like M2, F4, F5 and some of the Alephs.
Another way is to convert your speakers to 3way, but that might not be that easy.
The best option IMHO is parallel ACA which means building one more ACA amp, and running them in parallel mode as mono blocks.
I can assure you the sound will be magnificent.
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