The New Hypex Fusion Plate amps

I use chromecast wih a linear supply as a tidal digitaI source. I have a following question: how to connect two fa 123 (feeding two loudspeakers) with one fa 501 (sub)? FA 501 does not have spdif input on the panel.
High level input (fa 501) connected to both FA 123 (amp outuputs devoted to low freq) is the only way ?
thx
 
Poor SS woofer! Definitely don't need BTL for that, this is not a high load capacity driver, you would burn (or destroy because of xmech limit) it with BTL.

Tell it to my 2pcs of Peerless SLS woofer parallel connected to my fa 503 🙂 well, i know, don't need more than 200w rms for good sound, but much more power have only benefits. I can go with 253 and it will be sure enough, but I don't need 250w for 95db midrange driver and don't need 100w for cca 95db tweeter. So fa123 in btl make me sense
 
I would also consider to use the third speaker out of Fusion for this. You could add a resistor divider network to get output voltage to Line level and then directly connect to analog in of your sub.

If I understand your proposal correctly, I would lose an amp channel to the sub, and only be able to use my fa123 as a 2 way + sub setup, correct? That won't work for me as I want a 3-way + sub setup. Also it seems a bit wasteful dumping a lot of voltage into a resistor, but I get and appreciate the clever workaround
 
In the past I have built a sealed sub with FA 501.Sounds great with a classical stereo set up.
Now I am setting two FA 123 for 3 ways left and right.
Just I am wondering if there is a clever way to merge the sub (FA 501)
with two FA123, for a better bass reproduction.
It seems that the internal latency of FA 501 can not be avoided.
 
If I understand your proposal correctly, I would lose an amp channel to the sub, and only be able to use my fa123 as a 2 way + sub setup, correct? That won't work for me as I want a 3-way + sub setup. Also it seems a bit wasteful dumping a lot of voltage into a resistor, but I get and appreciate the clever workaround

Then I misunderstood what you need. Indeed I thought you wanted two way plus sub. With three way, using analog speaker output for sub makes much less sense, though it is not totally impossible if natural roll off is used of woofer or a passive HPF is used on woofer...
 
Then I misunderstood what you need. Indeed I thought you wanted two way plus sub. With three way, using analog speaker output for sub makes much less sense, though it is not totally impossible if natural roll off is used of woofer or a passive HPF is used on woofer...
Thank you for this commentm, it makes the idea less attractive.

How we should connect power cable to FA, where the hot cable should go? Down or up? Please see the attached picture. Can you advice?

YSDR, upon connection scenario: High level input (fa 501) connected to both FA 123 (amp outputs) devoted to low freq, the latency in fa 501should be considered, do you agree?
 

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@gothi: Assuming you use one of the FA123's as master, the other FusionAmps as slaves.

What input do you want to use for the FA123's? I think SPDIF
- If SPDIF or Toslink (which as you stated FA501 lacks), why not use a cheap SPDIF/Toslink to Analog converter? You can connect the L and R outputs to the corresponding RCA inputs of the FA501.
- In case you want to use AES, then you can use the SPDIF output of the Master FusionAmp and link that through to the other FusionAmps and the SPDIF to analog converter.
- If Analog then use Y cables to the lowlevel inputs.

Otherwise please give more information about what you hope to realise.
 
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...... Yes and no. If you have a 24-bit signal path, you can attenuate by 48 db or more before you start losing actual signal information. At that point, you wouldn't hear that information anyway.

Given that 16 bits is the input and gives "perfect sound forever"? 🙂 Maybe it does...

But its not all about number of bits - you do recalculate the whole word (whatever length) in a volume control and you will have rounding errors.

So, "before you start losing actual signal information", is a false statement. If this is audible is a different question.

//
 
@gothi: Assuming you use one of the FA123's as master, the other FusionAmps as slaves.

What input do you want to use for the FA123's? I think SPDIF
- If SPDIF or Toslink (which as you stated FA501 lacks), why not use a cheap SPDIF/Toslink to Analog converter? You can connect the L and R outputs to the corresponding RCA inputs of the FA501.
- In case you want to use AES, then you can use the SPDIF output of the Master FusionAmp and link that through to the other FusionAmps and the SPDIF to analog converter.
- If Analog then use Y cables to the lowlevel inputs.

Otherwise please give more information about what you hope to realise.
@gnl: thanks for the help, following your advice I see a scheme 1 as a very nice set-up 🙂

@YSDR: just to explain my previous proposition please see scheme 2
 

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Given that 16 bits is the input and gives "perfect sound forever"? 🙂 Maybe it does...

But its not all about number of bits - you do recalculate the whole word (whatever length) in a volume control and you will have rounding errors.

So, "before you start losing actual signal information", is a false statement. If this is audible is a different question.

//

Of course there will be rounding errors. But any noise generated from them, assuming a well thought out gain structure, will be insignificant.

A simple test is to take a 24 bit audio track. Reduce the bit depth by 8 -> 48 dB. Increase the volume by 48 dB. Then you can listen to the difference of the tracks. When I did the test I got pure noise, at such a low level that i do not worry about loosing bits anymore by attenuating the signal digitally at my source.
 
@gothi: you need to pass the S/PDIF signal through from the last FA123 to the FA501 remote input as well, in case you want to use a remote control.
The FA501 can also pass S/PDIF through to a FA123, so the order in this chain is not important.
 
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That is what I also wrote. However the remote input/output receives the remote signal via S/PDIF and also passes S/PDIF through. The S/PDIF audio signal cannot be processed by the FA501 due to the missing circuitry.


Sure, so the corrected scheme is given below. Just in case 🙂



Maybe it was discussed before, but I notice that FA 123 modules are hot even when I do not play music via SPDIF over hours, is there any way to make them cool upon such "stand by" period?



@fedde, you are corrrect, FA502 or FA252 would be great, but I have got already FA501
 

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