I liked the MAOP10 than the 10.3M. While they have the same mids and highs, the bass is more and I think it really optimizes the FHXL design. With the available bass power from the MAOP 10 one can tune the bass output by using the room boundaries since it is a rear ported baffle.
My room size is around 21sq.m. in area with a ceiling height of 2.8 meters. The room is trapezoid in shape and the ceiling is not flat but sloping
My room size is around 21sq.m. in area with a ceiling height of 2.8 meters. The room is trapezoid in shape and the ceiling is not flat but sloping
Hi, all the good ACA people! I am in my 50-ies and I never called myself an audiophile, but recently I became interested in the DIY electronics and that's how I ended up in waiting for my ACA kit to be delivered (customs takes ages). Meanwhile, until I can start enjoing the soldering, I wanted to understand better what kind of jewel the ACA is and how it will fit into my music experience. This message is going to be long and with many questions (that I numbered for easier reference of those who will be kind to responde), but I hope some good people will have patience to read it and help me to get oriented in this new to me audiophile world.
1) I had already made a pair of small but nice speakers called Overnight Sensations MT. I know they are not sensitive enough for ACA to enjoy them (just 83 dB), but they have a nice frequency response of 45-20,000 Hz (-3 dB) and, in my opinion, do a good job for their very small size (just 4.5 ltr). I like their sound and I am going to use them as my desktop speakers.
My theoretical knowledge tells me that 8W should give me 92 dB at the desk from one speaker, so 95 dB from 2 speakers, or about 83 dB at the couch 4 meters away.
Thats looks like good enough for me as I do not need it loud, but would like my music to be clean. Although, as I understand, the sound level at my couch will also depend on the strenght of the input signal. So, the first question:
(Q1) What signal lever ACA needs to give me the full 8W that it is capable to? Am I asking here about the Input Sensitivity of ACA to get the max output?
(Q2) What is the output level of the MacBook Pro or iPhone X that could be my initial source of Spotify music? Would it be enough for ACA?
2) Speaking about the music source. My main source will be Spotify Premium, capable of the 320 kbps of Ogg/Vorbis output. In my reckoning, that is good enough. More than I can hear anyway.
3) But then comes the DAC and the pre-amp (if I need any). And I would like to be sure that they don't spoil the party for the ACA ("garbage in - garbage out" as they say).
Some say MacBook Pro DAC is quite ok, others do not agree. DAC for the iPhone X is in the Lightning to 3.5 mm Headphone Jack adapter. Can it be good enough?
What if I go for the ALLO – The BOSS Player (ALLO - The BOSS Player * Volumio With its characteristics listed as DAC SNR is 112dB, DAC THD+N @ -1dBFS are –87dB, Dynamic Range of DAC is 112dB - it looks like capable more than Spotify gives, and it could be my wi-fi Spotify station for a very reasonable price of about EUR 160. I am ok wih software and programming, so I'm not afraid of the Rasbery Pi and Volumio.
(Q3) One of the characteristic says: Full Scale Output of DAC is 2.1Vrms. What does that realy mean? Would it be good enough to feed into ACA without the pre-amp?
4) If I need a pre-amp. What would you say about the Schiit Magni 3+? If I read the specs, it looks all good for me: Frequency Response: 20Hz-20Khz, +/-0.04dB, THD+N: on High Gain: Less than 0.0013% (-98dB) at 1V RMS into 32 ohms, SNR: on High Gain: Greater than 104dB, A weighted, referenced to 1V RMS. Gain: 1 (0db) or 5.5 (15db), selectable via rear switch.
(Q4) Am I right about this cheap pre-amp? What specs should I be looking for?
A whole lot of questions, I guess. Would anybody be kind to comment, please?
(Q5) One more... What is the power consumption of ACA?
Thanks to those who read all that
1) I had already made a pair of small but nice speakers called Overnight Sensations MT. I know they are not sensitive enough for ACA to enjoy them (just 83 dB), but they have a nice frequency response of 45-20,000 Hz (-3 dB) and, in my opinion, do a good job for their very small size (just 4.5 ltr). I like their sound and I am going to use them as my desktop speakers.
My theoretical knowledge tells me that 8W should give me 92 dB at the desk from one speaker, so 95 dB from 2 speakers, or about 83 dB at the couch 4 meters away.
Thats looks like good enough for me as I do not need it loud, but would like my music to be clean. Although, as I understand, the sound level at my couch will also depend on the strenght of the input signal. So, the first question:
(Q1) What signal lever ACA needs to give me the full 8W that it is capable to? Am I asking here about the Input Sensitivity of ACA to get the max output?
(Q2) What is the output level of the MacBook Pro or iPhone X that could be my initial source of Spotify music? Would it be enough for ACA?
2) Speaking about the music source. My main source will be Spotify Premium, capable of the 320 kbps of Ogg/Vorbis output. In my reckoning, that is good enough. More than I can hear anyway.
3) But then comes the DAC and the pre-amp (if I need any). And I would like to be sure that they don't spoil the party for the ACA ("garbage in - garbage out" as they say).
Some say MacBook Pro DAC is quite ok, others do not agree. DAC for the iPhone X is in the Lightning to 3.5 mm Headphone Jack adapter. Can it be good enough?
What if I go for the ALLO – The BOSS Player (ALLO - The BOSS Player * Volumio With its characteristics listed as DAC SNR is 112dB, DAC THD+N @ -1dBFS are –87dB, Dynamic Range of DAC is 112dB - it looks like capable more than Spotify gives, and it could be my wi-fi Spotify station for a very reasonable price of about EUR 160. I am ok wih software and programming, so I'm not afraid of the Rasbery Pi and Volumio.
(Q3) One of the characteristic says: Full Scale Output of DAC is 2.1Vrms. What does that realy mean? Would it be good enough to feed into ACA without the pre-amp?
4) If I need a pre-amp. What would you say about the Schiit Magni 3+? If I read the specs, it looks all good for me: Frequency Response: 20Hz-20Khz, +/-0.04dB, THD+N: on High Gain: Less than 0.0013% (-98dB) at 1V RMS into 32 ohms, SNR: on High Gain: Greater than 104dB, A weighted, referenced to 1V RMS. Gain: 1 (0db) or 5.5 (15db), selectable via rear switch.
(Q4) Am I right about this cheap pre-amp? What specs should I be looking for?
A whole lot of questions, I guess. Would anybody be kind to comment, please?
(Q5) One more... What is the power consumption of ACA?
Thanks to those who read all that
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More important then the sensitivity id the impedance trdponde, especially if you are using a pair of balanced/bridged monoBloks. The big peak at 2k may well be audiable.
I am a big Apple fan, but i fully expect that size restrictions make for compromises on the DACs, but perhaps not enuff to be an issue given the limted source material. You’ll just have to listen & see.
dave
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What impedance are they? 4 ohms 8 ohms?
Spec is 1.7 volts gets you 4 watts, figure.
No idea, but iphones and the like do not reach 0.5 volts.
That's a statement.
Volume control?
You need some gain, 10 to 15dB.
Too big a question.
Others will have other ideas...
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@planet10
Thanks. What is the source of the graph, please? I know the speakers are not the best, but that is something that I could easily build while waiting for the ACA.
@Allan44411
Perhaps I should not care about anything else if I start from Spotify and I'm not in Vinyl or FLAC?
For the The BOSS Player, volume control is via the mobile app or brower on the PC. You have to control your music from there anyway. But "mechanical" volume control could be a reason to put the pre-amp also.
Only I would like to understand what this "Full Scale Output of DAC is 2.1Vrms" means. If you say "1.7 volts gets you 4 watts", then could 2.1 volts perhaps give me 8 watts and that is all I need?
But would the quality of the sound it passes to the ACA be good enough?
Thanks. What is the source of the graph, please? I know the speakers are not the best, but that is something that I could easily build while waiting for the ACA.
@Allan44411
They are 8 ohms.
Perhaps I should not care about anything else if I start from Spotify and I'm not in Vinyl or FLAC?
For the The BOSS Player, volume control is via the mobile app or brower on the PC. You have to control your music from there anyway. But "mechanical" volume control could be a reason to put the pre-amp also.
Only I would like to understand what this "Full Scale Output of DAC is 2.1Vrms" means. If you say "1.7 volts gets you 4 watts", then could 2.1 volts perhaps give me 8 watts and that is all I need?
So Schiit Magni 3+ would give 15dB.
But would the quality of the sound it passes to the ACA be good enough?
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The Allo dacs for the Raspberry Pi are pretty good but you'll want to do a few things to get the best out of them.
Run the volume of the Boss dac at 100 percent. The internal volume control on the dac will lower the sound quality significantly and things won't sound anywhere near as good as they will if you run the dac volume at 100% and use an external volume control.
My preference for an Allo Piano 2.1 dac is Moodeaudio. Try it in addition to Volumio to see which works and sounds best to your ears.
A preamp is a good idea, both for the volume control and the additional gain. I've not tried the amp camp with unity gain but there are many on this board that have commented it sounds best with gain.
I've no experience with the preamp you've mentioned but it has gain and will allow you to run the Boss dac at 100%. That should be a large improvement and go a long way to make things sound great.
Run the volume of the Boss dac at 100 percent. The internal volume control on the dac will lower the sound quality significantly and things won't sound anywhere near as good as they will if you run the dac volume at 100% and use an external volume control.
My preference for an Allo Piano 2.1 dac is Moodeaudio. Try it in addition to Volumio to see which works and sounds best to your ears.
A preamp is a good idea, both for the volume control and the additional gain. I've not tried the amp camp with unity gain but there are many on this board that have commented it sounds best with gain.
I've no experience with the preamp you've mentioned but it has gain and will allow you to run the Boss dac at 100%. That should be a large improvement and go a long way to make things sound great.
Just finished my build. Took the weekend because I work slowly. Lots of fun and a simple, straightforward build. Thanks everyone!
Powered up with that beautiful sound and was making music on the first test.
Only two tricky points:
DC balancing. A very small turn would send the measurement shoot off 1-2 volts, it took a while to find 10V on both sides.
Chassis. Its beautiful, but really hard to get everything to align. Yes, I know, leave all screws loose until all the parts are on--- but it is a little awkward trying to tighten up the interior screws once the top and bottom covers are in place.
Got it done and am a happy (amp) camper.
Powered up with that beautiful sound and was making music on the first test.
Only two tricky points:
DC balancing. A very small turn would send the measurement shoot off 1-2 volts, it took a while to find 10V on both sides.
Chassis. Its beautiful, but really hard to get everything to align. Yes, I know, leave all screws loose until all the parts are on--- but it is a little awkward trying to tighten up the interior screws once the top and bottom covers are in place
.Got it done and am a happy (amp) camper.
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overdriving the amp?
I'm sure Alan4411 is correct, though I couldn't find any spec on input levels (only checked the DIY store technical specifications sectionAmp Camp Amp – diyAudio Store and the original thread/article Amp Camp Amp #1 ).
We know if your input signal is only 0.5 volts (ie a smartphone) the amp is fine, if not as loud as one might like.
What happens if the input signal is closer to 10V? Is that going to blow anything? Or will I only see really bad clipping?
I ask because my Eurorack sequencer operates at +/- 10V (the standard for such systems), and I'd like to connect it to my amp.
Yes, when I get the linestage built, I'll route everything through that, but the linestage is still in its parts bag and I want to play now!
I'm sure Alan4411 is correct, though I couldn't find any spec on input levels (only checked the DIY store technical specifications sectionAmp Camp Amp – diyAudio Store and the original thread/article Amp Camp Amp #1 ).
We know if your input signal is only 0.5 volts (ie a smartphone) the amp is fine, if not as loud as one might like.
What happens if the input signal is closer to 10V? Is that going to blow anything? Or will I only see really bad clipping?
I ask because my Eurorack sequencer operates at +/- 10V (the standard for such systems), and I'd like to connect it to my amp.
Yes, when I get the linestage built, I'll route everything through that, but the linestage is still in its parts bag and I want to play now!
Spec is on the circuit diagram See enclosed.
I know nothing of the 'sequencer'. Is the output full all the time or can you turn it down? Ie have a volume or gain control? If in doubt, do not connect it. If you cannot 'turn it down' it will just clip very badly...
Just one more thing, if you are using the 24 volt smps (comes with the v1.6 and v1.8 kits) the 'bias' is set at 12 volts, not 10 volts.
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Doff! I should have thought to check there, yes of course it is. Thank you
Yes, the sequencer has an output gain control, which would remember to set properly most of the time--- I'd just be really sad if I forgot once and fried my amp.
From what you tell me, it would not damage the amp, it would just sound bad. I can live with that
Thanks for this! Amazing how I missed this info in the build guide, since it is in bold text...
Good to know that my amp will sound even better soon
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I will get in touch with you when I am able to report for owrk in Makati to make the transport easier.
Thanks in advance
Thanks in advance
It came from the Overnight sensation document i downloaded from Meniscus. I have had experience with this design, it is OK, but were outperformed by a set of EL70s ina similar size box and smoked them in a larger box. It was at a diyFEST and Bob ended up selling out of EL70s shortly after that. The impedance of a good FR is also more appropriate for a high Rout.
Nominal 8Ω, as can be seen from the actual impedance a much wilder ride.
The only person you need to satisfy is yourself. Try it, you might be fine.
dave
Parallel mono?
Sorry, I'm sure this has been addressed a few times but I'm looking for info about how to do a parallel mono config. I think I know how to do the hook up, but I'm not sure if I need to mod something internally? It's a v.1.6 , I never built the units but I am electronically capable...
Sorry, I'm sure this has been addressed a few times but I'm looking for info about how to do a parallel mono config. I think I know how to do the hook up, but I'm not sure if I need to mod something internally? It's a v.1.6 , I never built the units but I am electronically capable...
You don’t need to but the only parts difference between the 1.6 and 1.8 is a DPDT ON-OFF-ON switch. ( and a rear panel with a concise diagram of the various hookup options, which will someday be available separately. ) So you might as well get one of those and build a 1.8 since you are interested in monoblocks. There is a link to one Of these switches on this thread or the ACA premium parts thread. Other than that is only the revised wiring as show in the wiring diagram. The new scheme allows you to switch to various mono configs with pretty much flicking a switch.
The switch would be in the Parallel position, if you’re using the 1.8 wiring:
Amp Camp Amp V1.8 Build Guide - diyAudio Guides
Amp Camp Amp V1.8 Build Guide - diyAudio Guides
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