Hello
So what i have been trying is to get a youtube video with mono vs stereo and speaker test that swaps left/right with same sound.
It's clear that in every case one channel is significant better than other, if i swap the rca between B1 and ACA the also swaps.
I have tested 3 different rca cables now.
Also i have the speaker phase as in the B1 pdf where Nelson says to swap at the speaker connection the phase.
But what i have not tried yet is to put them in normal phase.
If i just swap speakers nothing changes.
In my mind, if when i swap left/right in rca that connects the B1 to ACA and the significant difference in output also swaps then must be the B1. Or i am so noob i just to wrong conclusion?
What do you think?
UPDATE: So i connect directly my mobile phone to ACA and both channels are at same level.
Meaning for sure it's the B1, now how do i find out what is the problem?
So what i have been trying is to get a youtube video with mono vs stereo and speaker test that swaps left/right with same sound.
It's clear that in every case one channel is significant better than other, if i swap the rca between B1 and ACA the also swaps.
I have tested 3 different rca cables now.
Also i have the speaker phase as in the B1 pdf where Nelson says to swap at the speaker connection the phase.
But what i have not tried yet is to put them in normal phase.
If i just swap speakers nothing changes.
In my mind, if when i swap left/right in rca that connects the B1 to ACA and the significant difference in output also swaps then must be the B1. Or i am so noob i just to wrong conclusion?
What do you think?
UPDATE: So i connect directly my mobile phone to ACA and both channels are at same level.
Meaning for sure it's the B1, now how do i find out what is the problem?
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Ok... i found it.
Decided to disassemble the B1 and check everything one by one and found that i did a bad soldering job in a 10uf cap on the top right side just above JQ1.
Now is fixed and sound is as perfect as i can get it!
Really happy.
Thank you all for your time and help!
You all great.
Decided to disassemble the B1 and check everything one by one and found that i did a bad soldering job in a 10uf cap on the top right side just above JQ1.
Now is fixed and sound is as perfect as i can get it!
Really happy.
Thank you all for your time and help!
You all great.
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Hi, my name is Paul from Dublin Ireland, i have been lurking here for a while and learnt alot from all the contributions from the members of the forum...thanks
I was wondering how would I connect my 2 ACA 1.8 with 2 REL subwoofers..I was looking at the REL website and it said:
Balanced Differential monoblocks differ considerably from common single ended mono block amps and these differences can have important consequences when it comes to connecting RELs to your mono blocks. Get it wrong and you could be chasing ground loop-induced hum. Worse, in some cases, amplifiers can load down and run hot so it pays to get this connectivity right from the start.
It is beyond the scope of this brief educational piece to dive into a lengthy engineering description of the various topological differences between differential and single-ended amps. Note: Balanced inputs on your mono blocks does NOT mean you own differential amps. We are concerned about the output design (differential or common single-ended), NOT whether your amp uses XLR input connectors. Call your amp manufacturer and ask them if you have questions about what you own.
So the ACAs are single ended right and therefore not differential amps rather common single ended?
Amy help would be greatly appreciated!
I was wondering how would I connect my 2 ACA 1.8 with 2 REL subwoofers..I was looking at the REL website and it said:
Balanced Differential monoblocks differ considerably from common single ended mono block amps and these differences can have important consequences when it comes to connecting RELs to your mono blocks. Get it wrong and you could be chasing ground loop-induced hum. Worse, in some cases, amplifiers can load down and run hot so it pays to get this connectivity right from the start.
It is beyond the scope of this brief educational piece to dive into a lengthy engineering description of the various topological differences between differential and single-ended amps. Note: Balanced inputs on your mono blocks does NOT mean you own differential amps. We are concerned about the output design (differential or common single-ended), NOT whether your amp uses XLR input connectors. Call your amp manufacturer and ask them if you have questions about what you own.
So the ACAs are single ended right and therefore not differential amps rather common single ended?
Amy help would be greatly appreciated!
If you use the high level inputs on the subwoofer and connect them with the same polarity as you have connected to your main speakers. You should be just fine. The high level inputs are very high impedance. Your amp will be blissfully unaware that the subs are even there.
In short. Parallel the connections that already feed your main speakers.
In short. Parallel the connections that already feed your main speakers.
@sparkplug,
I would be more cautious.
First explain how your ACAs are used. You say you have 2 so are they bridged monos or parallel connected?
Then does the REL sub have any connection to earth? If so is one of the input connections connected to that earth?
Remember that the ACA has its RED speaker terminals connected to Earth from the power supply.
Answer to your second question, no.
I would be more cautious.
First explain how your ACAs are used. You say you have 2 so are they bridged monos or parallel connected?
Then does the REL sub have any connection to earth? If so is one of the input connections connected to that earth?
Remember that the ACA has its RED speaker terminals connected to Earth from the power supply.
Answer to your second question, no.
As always: Good points, Alan.
On the high level input. Mine measure 1.5 k from each terminal (red and black): to earth. Very tiny amount of current flows through the connecting cable. Hope this helps!
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All excellent points from all above. REL should have some guidance re: specific products and how to wire them with various amps. I'll chime in re: the ACA just in case with a bit more detail.
Tying the previous posts together. I'll assume you built and wired your 1.8s exactly per the guide and that you've set the switch for bridged XLR. See step 15 in the temporary 1.8 guide if you're unsure re: hookups. I'll further assume that they make beautiful music when connected to your favorite speakers, and that they're fed from a pre-amp or source with a balanced / differential output vs. one with just XLRs on the back.
All that out of the way...
SIGNAL
No one has mentioned WHICH black speaker terminal on each amp. The non-inverted signal is output through the black speaker terminal B on the ACA. See your wiring diagram. Pin 2 of your XLR goes to the "right channel", which is the 'B' side.
The high-level signal wire(s) going to each sub will go to the black speaker terminal 'B' on each ACA. If you connect to black terminal 'A', your subs would be out of phase with your main speakers. Also, don't wire one sub to 'A' of one amp and one to 'B' on the other amp. Why? Your subs would be out of phase with each other, and one will be out of phase with your main speakers.
GND
3 common options. Floating (not connected). Amp GND. Pre-Amp GND. Consult your manual. If in doubt, ask REL.
Hope I got that right.
Tying the previous posts together. I'll assume you built and wired your 1.8s exactly per the guide and that you've set the switch for bridged XLR. See step 15 in the temporary 1.8 guide if you're unsure re: hookups. I'll further assume that they make beautiful music when connected to your favorite speakers, and that they're fed from a pre-amp or source with a balanced / differential output vs. one with just XLRs on the back.
All that out of the way...
SIGNAL
No one has mentioned WHICH black speaker terminal on each amp. The non-inverted signal is output through the black speaker terminal B on the ACA. See your wiring diagram. Pin 2 of your XLR goes to the "right channel", which is the 'B' side.
The high-level signal wire(s) going to each sub will go to the black speaker terminal 'B' on each ACA. If you connect to black terminal 'A', your subs would be out of phase with your main speakers. Also, don't wire one sub to 'A' of one amp and one to 'B' on the other amp. Why? Your subs would be out of phase with each other, and one will be out of phase with your main speakers.
GND
3 common options. Floating (not connected). Amp GND. Pre-Amp GND. Consult your manual. If in doubt, ask REL.
Hope I got that right.