Hi, I begin to see some offering of amps based on nc500. Tempted. But I am really curious about the nc500 adapter board, which has a jumper to set the input buffer at either 0db or 14.6db.
I suppose that won't change the overall gain, but instead affect the input sensitivity?
If I am bi-amping my loudspeaker, with nc500 amp driving the woofer, and if I need to EQ the LF drastically (which will reduce the SPL of LF compared to mid & HF and create unbalance), will this input buffer help?
I suppose that won't change the overall gain, but instead affect the input sensitivity?
If I am bi-amping my loudspeaker, with nc500 amp driving the woofer, and if I need to EQ the LF drastically (which will reduce the SPL of LF compared to mid & HF and create unbalance), will this input buffer help?
The input buffer is required. Your not gonna find any of the commercial NC500's that don't have an input buffer.
[help=]%[/help]
Hi, the adapter board (input buffer board) has a jumper to choose either 0db or 14.6db gain. So there are no much to play with that jumper setting? Thanks again.
BTW, Some of the DSP module offers input gain (like QSC) that will compensate spl loss in EQing. Some not.
Hi, the adapter board (input buffer board) has a jumper to choose either 0db or 14.6db gain. So there are no much to play with that jumper setting? Thanks again.
BTW, Some of the DSP module offers input gain (like QSC) that will compensate spl loss in EQing. Some not.
You can't change one without changing the other. They are different aspects of the same thing.
Input sensitivity is maximum output voltage divided by the overall (voltage) gain.
hypex ncore
Do you have an NC500 with the Hypex buffer board in your possession?
Or did you buy the Acoustic Imagery Atash 500?
Because it's the only NC500 based amp I know of that uses the board.
That jumper is to bypass the onboard opamp. If you do that you better have something with a lot of balls to drive it.
[help=]%[/help]
Hi, the adapter board (input buffer board) has a jumper to choose either 0db or 14.6db gain. So there are no much to play with that jumper setting? Thanks again.
BTW, Some of the DSP module offers input gain (like QSC) that will compensate spl loss in EQing. Some not.
Do you have an NC500 with the Hypex buffer board in your possession?
Or did you buy the Acoustic Imagery Atash 500?
Because it's the only NC500 based amp I know of that uses the board.
That jumper is to bypass the onboard opamp. If you do that you better have something with a lot of balls to drive it.
Atash is one potentail candidate. Some one is going to offer nc500 based for cheaper. And maybe more.
Anyhow, Atash claims that their amp will be good choice when people consider bi-amping and I agree -- nc500 to drive the woofers may produce satisfactory S.Q. However, many may also want to add EQ to bass. And some DSP modules really do not boost the bass and the total SPL of LF may be too low to balance with Mids & High.
That was why I asked the question. I think there should be very easy solution if some knowledgeable people really wants to do it.
Last edited:
It sounds like bypassing the opamp isn't the way to do it. I am not really sure I understand your problem. If the low frequency output isn't strong enough compared to mids and highs, just turn down mids and highs and increase overall gain. Either your DSP system can produce a voltage that is high enough to drive the amps, or it can't. If it can't, you have the wrong overall gain structure.
Will someone please reply
Also realised that maybe I should go from pin1 to the XLR ground pin and then from that pin to ground.
Sorry for not responding, but I can't remember the wire colours, so would have to open up one of my amps to check.
But yes, XLR Pin 1 with a short lead to chassis (and if your XLR connector body doesn't make metallic contact with the chassis, also connect XLR body ("ground pin") to chassis/pin1. Pins 2 and 3 to the nc400 input leads.
nAMPON (and wire braid) to chassis.
Julf, thanks.
If I use MiniDSP, it won't work since it won't give input gain and which means lower SPL after EQ. If I use QSC DSP, it will work since it offer gains, but then SQ-wise it is not as good (but it is fine) and it is not easy to fit inside a chassis. That has been the problem for me when I use nc400 amps for driving woofers only. Guess I will still face the problem with nc500.
By the way, I also have plate amps but then the EQ with plate amp are not as versitle and the S.Q. cannot compare to ncores.
Thought that the input buffer on the nc500 adapter board will solve my problem but turns out not neccessarily.
Last edited:
Again, EQ doesn't really factor into it. The MiniDSP can work at unity gain (neither amplifying or attenuating, but just reproducing at exactly the same level). So if your preamp can produce a high enough output amplitude, and the MiniDSP could handle the amplitude to drive your nc400/nc500 to full output, then it is just a question of adjusting highs/mids to the appropriate level.
The real issue is that the MiniDSP Rev A can only handle 0.9V, so you need a buffer stage - but that is a limitation of the MiniDSP not being compatible with the rest of your audio chain. You need a more sensitive power amp, or an intermediate buffer stage.
Hi, Julf,
In my bi-amping setup, my preamp has two RCA output, one goes to first watt J2 driving widebander, the other goes to nc400 driving woofers.
Now, if I don't do any EQing, it is fine. The sound is balanced. When I use EQ through MiniDSP, the LF SPL will be lower than Mid & HF. When I use EQ through QSC DSP, QSC will give me enough option to balance the sound again. Not sure if that is due to MiniDSP's limiting ability of handling 0.9V input only. But the preamp gain won't help here.
Anyhow, QSC & plate amp solve a lot of the problem for me. I do hope that I can figure a way out to use MiniDSP as well since I can hide them inside the chassis.
Maybe I should look for other DSP units offerings out there. I looked before, but not many choices out there.
Last edited:
Thanks Julf. I was going to connect pin 1 to to the xlr body tag and then connect that tag to the chassis is that ok. The body is metal but just want to make sure.
One other thing is should the DC offset be checked or is it usually done at QC.
If I need to do it is there a step by step guide.
I checked all 8 modules I have, and they were all within spec, but it is very easy and quick to check them, so I see no reason not to do it. Just use a DC volt meter (multimeter) to measure the output voltage with the input shorted.
Can't you turn up the gain of the preamp (and compensate by turning down the mid and high in the MiniDSP)?
The J2 has a input sensitivity of 1.4V for full power, while input sensitivity of the nc400 is 2V - still not a huge mismatch, but the MiniDSP will never be able to drive either one to full rated power.
Seriously I don't know how anyone is going to be able to offer NC500 based mono blocks for cheaper than $1000 a piece without going bankrupt shortly after.
Hi, Julf,
The mids & highs do not go through MiniDSP for purity consideration. Only the LF, that is the part where EQ won't really much affect the S.Q.
- Status
- Not open for further replies.