I'm not sure what your plans are in the long term for mounting the Najda in the enclosure I am hoping that what you have is a temporary test setup.
You really need to get some smaller bolts particularly those for the IEC inlet as they look to be very close to the terminals and you have not insulated the connections this could arc between the live and the chassis. The simplest solution until you get some more bolts is to make sure the excess thread is outside of the case by mounting them the other way.
The safety earth should be a short wire that connects directly to the chassis. I prefer to use Crimp connectors for mains power as they are easy to remove and can be insulated to make things safer. I have attached a picture of a power inlet from an amplifier I have built to give you an idea of what I am describing.
Good luck with your project 🙂
You really need to get some smaller bolts particularly those for the IEC inlet as they look to be very close to the terminals and you have not insulated the connections this could arc between the live and the chassis. The simplest solution until you get some more bolts is to make sure the excess thread is outside of the case by mounting them the other way.
The safety earth should be a short wire that connects directly to the chassis. I prefer to use Crimp connectors for mains power as they are easy to remove and can be insulated to make things safer. I have attached a picture of a power inlet from an amplifier I have built to give you an idea of what I am describing.
Good luck with your project 🙂
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The wooden block is temporary. I have some standoffs left from PCs I intend to use.
Shorter screws for IEC socket, some shrinkwrap and shorter Earth path:
Shorter screws for IEC socket, some shrinkwrap and shorter Earth path:
What you have there is much better than before but the safety earth is still not right.
You need to drill a hole through the case don't use the cutouts.
Scrape off the paint where the washer contacts the case as you need metal to metal contact.
The earth wire needs to be physically connected to a ring terminal so everything has good electrical contact. At the moment you just have the wire tucked under the washer and there is no electrical connection to earth. This provides you no safety whatsoever.
Maybe do a search on safety earth wiring here or check out Rod Elliotts article
Earthing (Grounding) Your Hi-Fi - Tricks and Techniques
You need to drill a hole through the case don't use the cutouts.
Scrape off the paint where the washer contacts the case as you need metal to metal contact.
The earth wire needs to be physically connected to a ring terminal so everything has good electrical contact. At the moment you just have the wire tucked under the washer and there is no electrical connection to earth. This provides you no safety whatsoever.
Maybe do a search on safety earth wiring here or check out Rod Elliotts article
Earthing (Grounding) Your Hi-Fi - Tricks and Techniques
I drilled a hole through the cutout, removed the paint with a chisel and tightened the screw with a nut under the enclosure. I don't see how a ring terminal will make a better electrical contact considering the force with which the copper wire is pushed against the unpainted chassis. (you can see scratches next to the washer and see that it is bent due to the force of the nut)
The reason for the ring terminal is to allow a good mechanical connection and ensure that it won't easily come loose through friction.
In a DIY chassis the safety earth is the one part that you want to get right because if there is ever an issue it may save your life or whoever is unlucky enough to touch the chassis if there is a fault.
It's your project though...
In a DIY chassis the safety earth is the one part that you want to get right because if there is ever an issue it may save your life or whoever is unlucky enough to touch the chassis if there is a fault.
It's your project though...
Any one using Najda as part of surround setup
Hi I want to build a 3-way active speaker with Najda, already bought a pair of Emotive XPA-5 so I have power enough 😉
Can I connect the analog front L/R output from my Marantz AV-7500 preamplifier to the Najda and control the volume from the Marantz?
The Marantz has balanced out and I am planning on buying the the new analog board that is made for Najda.
Any problems with this setup, I really want to be able to use the new speaker will watching movies
Hi I want to build a 3-way active speaker with Najda, already bought a pair of Emotive XPA-5 so I have power enough 😉
Can I connect the analog front L/R output from my Marantz AV-7500 preamplifier to the Najda and control the volume from the Marantz?
The Marantz has balanced out and I am planning on buying the the new analog board that is made for Najda.
Any problems with this setup, I really want to be able to use the new speaker will watching movies
Hi Martin,
You can certainly connect it up that way and control the volume from the Marantz.
There are two issues you will have to deal with
1. If you listen at low volume from the Marantz then there will only be a small signal going into the Najda analogue input and this will likely limit the overall sound quality from the extra conversion. As long as you keep the signal level high enough this problem goes away.
2. The Najda analogue input will clip at a certain point so you will need to perform a test to see where or if this happens at a given volume on your marantz and make sure you don't go beyond this point as the sound of a clipped Najda is not good. There is an AD clip LED so it is easy to see when you have gone too far.
As noted in the manual Najda needs a little bit more headroom that some other DSP systems to avoid clipping.
Active speakers and surround sound are complicated to set up due to the number of channels required. The way you describe is probably the simplest way to bring an active speaker into your setup.
You can certainly connect it up that way and control the volume from the Marantz.
There are two issues you will have to deal with
1. If you listen at low volume from the Marantz then there will only be a small signal going into the Najda analogue input and this will likely limit the overall sound quality from the extra conversion. As long as you keep the signal level high enough this problem goes away.
2. The Najda analogue input will clip at a certain point so you will need to perform a test to see where or if this happens at a given volume on your marantz and make sure you don't go beyond this point as the sound of a clipped Najda is not good. There is an AD clip LED so it is easy to see when you have gone too far.
As noted in the manual Najda needs a little bit more headroom that some other DSP systems to avoid clipping.
Active speakers and surround sound are complicated to set up due to the number of channels required. The way you describe is probably the simplest way to bring an active speaker into your setup.
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What Microphone to buy?
I guess that we all know about the UMIK-1 but will it work with the NUC software? I know that it works very well with REW.
Are there other microphones out there that is better suited for the NUC software?
PS I would like to thank @fluid #2887 for removing a big burden from my shoulders🙂
I guess that we all know about the UMIK-1 but will it work with the NUC software? I know that it works very well with REW.
Are there other microphones out there that is better suited for the NUC software?
PS I would like to thank @fluid #2887 for removing a big burden from my shoulders🙂
Hi Martin,
Glad to be able help 🙂
The NUC software doesn't work directly with microphones.
You are able to view data that is saved in a text format like .frd and then see what effect the filters will have.
You will still need to use another program such as REW to record the response of the target speaker and then export to FRD if you want to be able to view it in NUC. The manual has a section on how to do this.
The UMIK is good because it is easy to connect and minidsp supply a calibration file which makes it pretty accurate. For the price it is hard to do much better particularly if you don't already have a mic preamp and a good soundcard.
Glad to be able help 🙂
The NUC software doesn't work directly with microphones.
You are able to view data that is saved in a text format like .frd and then see what effect the filters will have.
You will still need to use another program such as REW to record the response of the target speaker and then export to FRD if you want to be able to view it in NUC. The manual has a section on how to do this.
The UMIK is good because it is easy to connect and minidsp supply a calibration file which makes it pretty accurate. For the price it is hard to do much better particularly if you don't already have a mic preamp and a good soundcard.
NUC software compared to miniDSP software
I just read the NUC manual a couple of times and googled for articles describing how to build a speaker with the NUC. But no luck )-:
I have read the hifi zine and there are excelent. Looks like the miniDSP software are very easy to use compared to NUC. No gain structure to mess around with.
I really think the NAJDA board is the best but if I can't figure out how to use the it, then I will be better of with the "iPhone" solution
I just read the NUC manual a couple of times and googled for articles describing how to build a speaker with the NUC. But no luck )-:
I have read the hifi zine and there are excelent. Looks like the miniDSP software are very easy to use compared to NUC. No gain structure to mess around with.
I really think the NAJDA board is the best but if I can't figure out how to use the it, then I will be better of with the "iPhone" solution
You need to be careful with gain structure with minidsp too. The difference is that Nick has described this in depth, while minidsp hasn't. Najda also adds more flexibility on the analogue side due to the integrated CS3318 chips. I have used both platforms, and NUC is the better GUI too. If you want to build a speaker, the NUC manual won't be the place to start. Try diyaudio and linkwitz labs, troels gravesen etc.
I just read the NUC manual a couple of times and googled for articles describing how to build a speaker with the NUC. But no luck )-:
...
I really think the NAJDA board is the best but if I can't figure out how to use the it, then I will be better of with the "iPhone" solution
You need amp(s) too, which are not described either in NUC manual. Najda has basically 3 functions
- a digital crossover
- a multi-channel DAC
- multi channel preamp with volume control
You must know what is a crossover to use najda in most cases (if you are multi amped), but principles are the same as with other boards. Read the thread and the NUC manual carefully and you will get all answers, and you can train really easily.
BR
Jean-Louis
Martin,
The document below discusses working with design targets in NUC and was posted in the thread
Charlie Laub's Active Crossover design tools has a lot of information documents included which may be helpful.
NUC is not speaker design software it just allows to you to display FRD data and see how that is affected by the filters you choose.
Designing your own active speaker is not really a simple matter there is a lot of information you need to understand to get a good result. DSP is great but you need to know how to use it.
If gain structure is something that will put you off then I think you will have a lot of reading and researching to do before trying to design your own active system.
You might find it easier to try and copy an existing design and implement an active crossover for it. At least you will be close and can then tweek to make improvements based on measurements.
The document below discusses working with design targets in NUC and was posted in the thread
Charlie Laub's Active Crossover design tools has a lot of information documents included which may be helpful.
NUC is not speaker design software it just allows to you to display FRD data and see how that is affected by the filters you choose.
Designing your own active speaker is not really a simple matter there is a lot of information you need to understand to get a good result. DSP is great but you need to know how to use it.
If gain structure is something that will put you off then I think you will have a lot of reading and researching to do before trying to design your own active system.
You might find it easier to try and copy an existing design and implement an active crossover for it. At least you will be close and can then tweek to make improvements based on measurements.
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Power supply for Najda
@Zonneschimmel:
As I read in Your post # 2878, You use a power supply Cosel RMC15A-1. Are You sure that this one provides enough current?
Najda requires a minimum current of 0.5A / 5V, 0.35A / +12V and 0.25A /-12V (Recommended values: 1A / 1A / 0.3A).
The cosel RMC15A-1 data sheet says: 2A / 5V, 0.3A / +12V, 0.2A / -12V.
Maybe the Cosel RMC30A-1 suits better: it provides 3A / 1.2A / 0.3A.
Does the Cosel run without minimum load?
Who recommended the Cosel PSU, are there positive experiences?
Anyone with other recommendations for a PSU suiting the Najda?
@Zonneschimmel:
As I read in Your post # 2878, You use a power supply Cosel RMC15A-1. Are You sure that this one provides enough current?
Najda requires a minimum current of 0.5A / 5V, 0.35A / +12V and 0.25A /-12V (Recommended values: 1A / 1A / 0.3A).
The cosel RMC15A-1 data sheet says: 2A / 5V, 0.3A / +12V, 0.2A / -12V.
Maybe the Cosel RMC30A-1 suits better: it provides 3A / 1.2A / 0.3A.
Does the Cosel run without minimum load?
Who recommended the Cosel PSU, are there positive experiences?
Anyone with other recommendations for a PSU suiting the Najda?
It was recommended to me by chaparK but it turned out to be a 110V only model.
Alternatives are the Cosel LDC15F-1-SN
LDC15F-1-SN Cosel | Mouser
Or the Skynet SNP-9021-1
http://www.skynetpower.com.tw/pdf/SNP-902Series.pdf
I will be using the skynet, hopefully it arrives today or tomorrow.
Alternatives are the Cosel LDC15F-1-SN
LDC15F-1-SN Cosel | Mouser
Or the Skynet SNP-9021-1
http://www.skynetpower.com.tw/pdf/SNP-902Series.pdf
I will be using the skynet, hopefully it arrives today or tomorrow.
PSU for Najda
Thanks Zonneschimmel,
oh, yes, the RMC15 is a 110 Volt type, oops!
The skynet SNP-9021-1 seems rare, I don´t find a source for it.... (But already have one that works fine with my own Najda)
But it´s good news that there is this Cosel LDC15F-1-SN available at Mouser.
(Even though I`m wondering if the LDC30F-1-SN would´nt suit the current recommendations better....but if Chapark told You, it surely works!)
Thanks Zonneschimmel,
oh, yes, the RMC15 is a 110 Volt type, oops!
The skynet SNP-9021-1 seems rare, I don´t find a source for it.... (But already have one that works fine with my own Najda)
But it´s good news that there is this Cosel LDC15F-1-SN available at Mouser.
(Even though I`m wondering if the LDC30F-1-SN would´nt suit the current recommendations better....but if Chapark told You, it surely works!)
I know that it ain't easy
I have build speakers before with passiv components so I know how to design a passiv filter, not a Jedi master, but I am OK (-:
I decided to go the active route because
I know I am going to generate a lot of noise in this forum but I promise to dokument my journey in a new blog on diyaudio.
And I also solemnly swear to RTFM 😀
I have build speakers before with passiv components so I know how to design a passiv filter, not a Jedi master, but I am OK (-:
I decided to go the active route because
- Passiv component are very exspensiv.
- 24 L/R bandpass of good quality components fills a large sofa table.
- I am building a dipole speaker and need to equalise the bass with 6 db.
- Shelf and notch filters are hard to get right with passiv.
- I can play with a 48 LR filter with FIR - awesome
I know I am going to generate a lot of noise in this forum but I promise to dokument my journey in a new blog on diyaudio.
And I also solemnly swear to RTFM 😀
Im planning some rework of my Najda setup this winter. An additional "Unbalancer" buffer, actually three new ones on PCB's this time.
It wont fit in the old case so that's being rebuilt as well. I'm also planning a switch from spdif to I2s.
A friend of mine is setting up a five-way system also using "Najda" and a bunch of Buffalo dacs, so I will be invalved there as well I guess.
I have searched for a "how to" on the I2s output connection but without any luck so far. What's being connected for me are three Buffalo dacs.
So, two questions:
Is there a "how to" on I2s output connection somewhere in this thread that I have missed ?
Is there a possibility to get a five-way I2s output ?
It wont fit in the old case so that's being rebuilt as well. I'm also planning a switch from spdif to I2s.
A friend of mine is setting up a five-way system also using "Najda" and a bunch of Buffalo dacs, so I will be invalved there as well I guess.
I have searched for a "how to" on the I2s output connection but without any luck so far. What's being connected for me are three Buffalo dacs.
So, two questions:
Is there a "how to" on I2s output connection somewhere in this thread that I have missed ?
Is there a possibility to get a five-way I2s output ?
What I2S solution are you planning?
I made the switch a while back and used WaveIO.
Great sounding bit of kit. Quite a SQ leap over SPDIF.
At that time I cast around for some help on how to connect it up and I got a helpful pin to pin diagram.
I still have it, as a spreadsheet if you want a look.
I made the switch a while back and used WaveIO.
Great sounding bit of kit. Quite a SQ leap over SPDIF.
At that time I cast around for some help on how to connect it up and I got a helpful pin to pin diagram.
I still have it, as a spreadsheet if you want a look.