GentleEars
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My AUDIOPHONICS MPA-S252NC feeds a pair of B&W 685 (1st gen) speakers. They are rated 8 ohms. and sensitivity is 88dB.
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NCORE MP Build using Ghentaudio Kit.
- Thread starter decoRyder
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My AUDIOPHONICS MPA-S252NC feeds a pair of B&W 685 (1st gen) speakers. They are rated 8 ohms. and sensitivity is 88dB.
Yes, but I think that NCxxxMP modules are already DC protected, I prefer to not add another active component in the signal path
Nice speakers, a friend of mine have a pair
I'm looking to power some R900 with NC252mp, NC250mp, NC400, or NC1200s. What is "speaker protection?" Is it something that shuts off the amplifier before it blows up the speaker from too much/little power? Is it just to stop the pop from turning on/off? Does anyone know the SINAD of NC250mp? I have found for the others. Thank you in advance.
How would the amp know what is too much power for your specific speaker? How do you blow up a speaker from too little power?
Protection systems in amps are normally against faults like excessive current or DC.
I thought maybe it is similar to a circuit breaker, or recognizes the capability from the internal crossover and deals with it accordingly (I don't know what it can do). Maybe, when the amp is being pushed over max levels, it shuts itself off at some point to protect the amp circuitry? Or internal temperature gets too hot? When you say it protects against excessive current or DC, are you saying that the "protection" mechanism is for solely for the popping issue that I just read about - turning on/off - and nothing else (similar to safe start)? Again, I don't know. I asked to get some clarification since I couldn't read any specific information about what it does (I'm new. Not a designer of DIY, nor have I done DIY).
Does anyone know the SINAD on the NC250mp? I assume higher than NC252mp's ~94-95dB, but by how much?
Thanks for the patience with such dull questions.
No, you are actually pretty right about the "being pushed over max limits" part - it protects against exceeding current and heat limits, it just doesn't necessarily protect the speakers.
My apologies for my previous message being rather short and snappy, I was in a bit of a hurry.
Acording to Hypex, both NC250MP and NC252MP have the same specs, at the exception of the power at 8 Ohms (130W vs 150W).
Ah ok, I thought maybe being monoblock, there might be a small increase to ~96 or so. Thank you, I guess I will consider the NC400 then...but then R900 has high sensitivity and relatively speaking, the benefit of NC400 over NC250/252mp is in 2Ohm availability, which is unnecessary for R900?
No worries, written format leaves out a lot of context. I'm just glad people are willing to donate time to answer questions at all.
The protection circuitry is independent of those above units, and one must purchase separately and attach? The one offered to me are finished ghentcases, so maybe better to start fresh. Do the FusionAmp plate amps have them? If so:
- Can I turn 2x FusionAmps into 2x monoblocks, since it even has DSP control? I would only need 2-way FusionAmp for the low/high FR? I assume I will have to drill the plate onto something...maybe the front and back of my old ATX tower, or acrylic panels from Home Depot for a "modern" look? haha
- Could someone point me to some threads to turn a plate amp into a monoblock? I assume people have done this before, but I don't know what terms to search. I guess I would like to understand how to rework circuitry to produce a speaker outputs for LF and HF. Do you have to rework crossover, or would the internal crossover of the speaker be doing that? Anything else I may be missing.
Thanks again.
An NC400 build is something completely different, you need to add the power supply, cabling is more complex. Budget is not the same either.
All Hypex amps have internal protection against overload. To protect your speakers, don't buy a too powerful amp
Maybe you should first clarify with yourself what you want to achieve. Why monoblocks? Why DSP? Why biamping?- Can I turn 2x FusionAmps into 2x monoblocks, since it even has DSP control? I would only need 2-way FusionAmp for the low/high FR? I assume I will have to drill the plate onto something...maybe the front and back of my old ATX tower, or acrylic panels from Home Depot for a "modern" look? haha
- Could someone point me to some threads to turn a plate amp into a monoblock? I assume people have done this before, but I don't know what terms to search. I guess I would like to understand how to rework circuitry to produce a speaker outputs for LF and HF. Do you have to rework crossover, or would the internal crossover of the speaker be doing that? Anything else I may be missing.
Thanks again.
Wouldn't the simple solution be, as a starter, converting a 2 channels plate amp (FAxx2) into a stereo integrated amplifier with DSP?
Or even simpler, like this thread, just take the stereo amplifier part from an FAxx2 and convert it into a stereo power amplifier?
For the mechanical part, the modules are screwed on the plate, moving them to a nice box is technically not too challenging.
I didn't say before, but the amps I mentioned above were optioned to me privately as finished products, at severe discounts.
But I would lose the SINAD?All Hypex amps have internal protection against overload. To protect your speakers, don't buy a too powerful amp
1) Great sound for value
2) I read that mono blocks have better measurements vs the stereo counterpart, and the price delta is not too much (at least for the offers I received). Also I am curious regarding the effect of cables. XLR vs speaker cable vs SpeakON.
3) Why not have DSP? Lets me skip buying a miniDSP SHD too.
4) I don't know, those FA amps generally seem to have 2 sets, so I figured why not keep them separate? I don't have to, and I read that it makes inconsequential difference anyway.
5) I could certainly do that too, but I thought maybe it would be cool (if no technical advantages) to have one FA amp powering woofers and the coaxial UniQ separately?
6) I could do that, sounds like the same as above, and my answer is same as above!
Thanks for your patience!
SINAD is noise and distortion. No direct link with amplifier power. Amir measures it at 5W, most of the time you will not exceed 1W. If you fear blowing your speakers, buy an amp that has no more power than what they can withstand.But I would lose the SINAD?
I really and sincerely don't want to be offensive, but you seem to be at the very beginning of your travel in understanding all this stuff.
Biamping with a DSP seems a bit complicated for starters.
If you want to achive great sound, a DSP with an UMIK are your friends.
So my advise would be to buy one FAxx2 plate amp, put all the boards in an aluminum box, and you will have a nice stereo amplifier with DSP in order to do some room eq.
Since those are larger floorstanding speakers, have you considered the NC502MP?
This is my fault for not being clear. I wasn't linking with amp power, just that buying lower power as you said, ie NC252mp at 94, would mean that I am losing SINAD vs NC400's 105 - and CD quality necessitates 96.
Yes, DSP will be happening because of the room difficulties. As for the complication aspect, I don't mind. I have engineers who I can hire to do the technical work. I just want to understand what I am trying to accomplish, because that's fun! Thank you for the advice on the plate amp. Is there a couple you recommend for the R900? PM works for this too.
That one was not offered to me, so no - just the ones mentioned. I simply do not know what to pair the R900s with. I have read a lot, but there's no clear answers. There are those who say that 1-5 watts are enough more than anybody, and it doesn't matter. Then there are those who say low-RMS Hypex sounded really hollow and thin, the sound only got richer sound once upgrading to 200+ rated Hypex.
So yes, as a newbie, I need some more context and objective guidance. My apologies for not being an audio pro! And thank you ASR as usual.
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Maybe an amp from a manufacturer that allow some days trial at home or money back? VTV has 30 days policy.
https://vtvamplifier.com/product/vtv-amplifier-stereo-hypex-nc502mp-ncore-amplifier-500wx2/
Not really. Very, very few recordings or domestic listening rooms come anywhere near 96 dB.
Ah ok well that's good to know! I was just worried because I got TIDAL Masters and was curious if I'd notice any difference. Thanks!
@Matias - I decided against VTV after the various threads here.
First time post here. I’m planning on ordering a Ghent case with solderless wiring for the NC502MP board (which is sitting naked in front of me right now), and would love to make sure I’m wiring it up the best way since this amp may be “the amp to end all amps” in my system.
My understanding is the Ghent case comes with wiring that connects the XLR Pin 1 ground connection to the board ground in the J4 H Box connectors for each channel instead of the case - which is the Pin 1 problem.
I’ve read so many posts in this forum on this subject but still not 100% sure so hoping others can verify.
Could I address this by having Ghent drill in a screw hole for a short wire grounding the pin 1 on each XLR connector for grounding to the case? (If there isn’t already a screw hole in these spots.) And disconnecting the cable in the Ghent wiring that connects the channel 1 and 2 grounds in J4.3 and J4.14 to the XLR Pin 1, provided that the board and heat sink is properly grounded via screws in the case?
Also, as I’ll be using a preamp with unbalanced connections, I’ll be looking to get a RCA to XLR cable with the ground unterminated on the RCA side.
Or should I just wire up the board the default way that Ghent ships it, and address the “Pin 1 problem” later if there is a grounding problem. It seems like many people are perfectly fine wiring the Ghent cases up with the supplied wiring.
Thanks
My understanding is the Ghent case comes with wiring that connects the XLR Pin 1 ground connection to the board ground in the J4 H Box connectors for each channel instead of the case - which is the Pin 1 problem.
I’ve read so many posts in this forum on this subject but still not 100% sure so hoping others can verify.
Could I address this by having Ghent drill in a screw hole for a short wire grounding the pin 1 on each XLR connector for grounding to the case? (If there isn’t already a screw hole in these spots.) And disconnecting the cable in the Ghent wiring that connects the channel 1 and 2 grounds in J4.3 and J4.14 to the XLR Pin 1, provided that the board and heat sink is properly grounded via screws in the case?
Also, as I’ll be using a preamp with unbalanced connections, I’ll be looking to get a RCA to XLR cable with the ground unterminated on the RCA side.
Or should I just wire up the board the default way that Ghent ships it, and address the “Pin 1 problem” later if there is a grounding problem. It seems like many people are perfectly fine wiring the Ghent cases up with the supplied wiring.
Thanks
tmtomh
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I have massive medium sensitivity speakers (89dB) and an Audiophonics Purifi-based stereo amp, and I hear the pop but it is extremely quiet. I don't always hear it from both channels - it's quiet enough that it depends where I am standing in the room when it happens, whether or not I hear it distinctly from both channels or just one.
Ok,
Just received my arduino, and made some quick tests.
The "mute then standby sequence" works for me, no more plops in the speakers when powering off the amp.
You can see/hear this little video:here
Now, I need to figure out how to integrate the arduino in the amp (i'm a software guy, not a hardware/sound/electronic engineer one ^^)
I guess using the Vout standby smps pin is ok, but what about ground loops and maybe other audio signal degradations ?
I'll replace the push button with an IR receiver, and maybe use a RGB led to indicate the amp state (standby/mute/on)
Just received my arduino, and made some quick tests.
The "mute then standby sequence" works for me, no more plops in the speakers when powering off the amp.
You can see/hear this little video:here
- the green led is on when PS enable pin is asserted
- the yellow led is on when mute pin is asserted
- the 'plop' doesn't seem as loud and scarry as it sounds in real (and my living room speakers 'plop' is far louder)
Now, I need to figure out how to integrate the arduino in the amp (i'm a software guy, not a hardware/sound/electronic engineer one ^^)
I guess using the Vout standby smps pin is ok, but what about ground loops and maybe other audio signal degradations ?
I'll replace the push button with an IR receiver, and maybe use a RGB led to indicate the amp state (standby/mute/on)
Just wanted to comment on the pops (NC400 XLR) I had using my Topping E30 as a source. I switched to a surround processor (IOTAVX 7.1) with balanced out and all the popping is gone. Don't know much about electronics, but I guess it has something to do with it being balanced. I can test it using RCA out from the processor if you want....but its a bit of a pain because some cables in my setup are a bit short and I can't just pull it out of my tv cabinet to do a quick swap.
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