Regarding the post directly above, would you then recommend a dual mono configuration with seperate transformers? Besides fixing the issue stated, what advantages/disadvantages would this provide over a single transformer used for two channels?
Also, I am confused by the recommendation for increasing PSU capacitance to greater than 10000uf "per rail." How many "rails" are there if both chips in the LM4780 kit are used?
Thanks!
Also, I am confused by the recommendation for increasing PSU capacitance to greater than 10000uf "per rail." How many "rails" are there if both chips in the LM4780 kit are used?
Thanks!
@TP143 - Yes, that would be my recommendation though it is not the only way to operate. Principal disadvantages are heat from the second supply, more space required, more money for the second transformer, and more complex wiring. The grounds are particularly nasty to resolve when you have two separate power supplies in the chassis, unless you run a pure dual mono (no interaction between the halves - no volume, no input switching). Advantages are better channel separation and a better power reserve.
Each power supply PCB generates two rails, one positive and one negative. I actually have 4 sets of rails, not two, as each transformer is coupled to two power supply boards (with the caution mentioned in my post above). So that's a total of 8 'rails'. This is because the poor MUR860s are used without a heatsink and can run pretty hot with just one LM4780 going full tilt.
You may be able to get away with one PSU board (hence two rails only) for both chips in the kit, if you go a bit easy on the volume control.
Each power supply PCB generates two rails, one positive and one negative. I actually have 4 sets of rails, not two, as each transformer is coupled to two power supply boards (with the caution mentioned in my post above). So that's a total of 8 'rails'. This is because the poor MUR860s are used without a heatsink and can run pretty hot with just one LM4780 going full tilt.
You may be able to get away with one PSU board (hence two rails only) for both chips in the kit, if you go a bit easy on the volume control.
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Hi all,
I am living in the Netherlands and have build a 6ch amp based on Dantimax LM4780 kits. I am using it to power my self build stereo 3 way speakers. Source is J RIVER MC were I do the crossover (LR2) and the pre-amp is the ASUS Xonar D2X. Compared to my previous used class D 2x 125W Amp it's just "high end"
For Low I am using 2 parallel kits (1 for each speaker)
For MID and High I am using 2 stereo kits (1 for each speaker)
A total of 4, with also 4 transformers. Low is using low voltage, and mid and high are using higher voltage.
Have a look at the electronics.Dantimax.dk site, you will find also Preamps.
I would like to upload a picture of my build, only way of doing it is to create a URL...? Any other way to upload?
I am living in the Netherlands and have build a 6ch amp based on Dantimax LM4780 kits. I am using it to power my self build stereo 3 way speakers. Source is J RIVER MC were I do the crossover (LR2) and the pre-amp is the ASUS Xonar D2X. Compared to my previous used class D 2x 125W Amp it's just "high end"
For Low I am using 2 parallel kits (1 for each speaker)
For MID and High I am using 2 stereo kits (1 for each speaker)
A total of 4, with also 4 transformers. Low is using low voltage, and mid and high are using higher voltage.
Have a look at the electronics.Dantimax.dk site, you will find also Preamps.
I would like to upload a picture of my build, only way of doing it is to create a URL...? Any other way to upload?
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lm4780
still kick myself for not using peters board.next build i guess.love the support he gives members that;s aw some next build will be based on his board even thought i planned on doing a point to point. but for now i have these to /t20090921_2115.htm222.73.161.158:8000/Installed_Description/200909/t20090921_2115.htm 4 baords from bulgaria any help i would appreciate suggestions?esspecially on resister values 5k 2watt?1 or % 5? 22k 1% OR 0.1% .1/4 watt?wow if i want to runn in parallel what to change in values? Gainclone-LM4780 BOM # Part Name Description Qty. 2 1K KOA 1/4W Metal Film Resistors
3 5.1K KOA 1/4W Metal Film Resistors
4 22K KOA 1/4W Metal Film Resistors
5 0.1uF Polyester MKT Capacitors
6 22uF Elan Electrolytic Capacitors
7 33uF Electrolytic Capacitors
8 3300uF Elan for Audio Electrolytic Capacitors
9 MU860 Diode
10 LM4780 Chip AMP
still kick myself for not using peters board.next build i guess.love the support he gives members that;s aw some next build will be based on his board even thought i planned on doing a point to point. but for now i have these to /t20090921_2115.htm222.73.161.158:8000/Installed_Description/200909/t20090921_2115.htm 4 baords from bulgaria any help i would appreciate suggestions?esspecially on resister values 5k 2watt?1 or % 5? 22k 1% OR 0.1% .1/4 watt?wow if i want to runn in parallel what to change in values? Gainclone-LM4780 BOM # Part Name Description Qty. 2 1K KOA 1/4W Metal Film Resistors
3 5.1K KOA 1/4W Metal Film Resistors
4 22K KOA 1/4W Metal Film Resistors
5 0.1uF Polyester MKT Capacitors
6 22uF Elan Electrolytic Capacitors
7 33uF Electrolytic Capacitors
8 3300uF Elan for Audio Electrolytic Capacitors
9 MU860 Diode
10 LM4780 Chip AMP
An externally hosted image should be here but it was not working when we last tested it.
what values indeed
based on what ive read im going with two sepperate supplies corlos fm regulated with a couple of mods.4 10000uf caps per board 4700 on amp pcb .parts are as follows
based on what ive read im going with two sepperate supplies corlos fm regulated with a couple of mods.4 10000uf caps per board 4700 on amp pcb .parts are as follows
1
0.18Ω
5W non-inductive, ceramics Resistors2
1K
1/4W Metal Film Resistors3
5.1K
1/4W Metal Film Resistors4
22K
1/4W Metal Film Resistors
5
0.1uF
phillips Capacitors
6
22uF
Electrolytic Capacitors7
47uF
Electrolytic Capacitors8
4700uF
Electrolytic Capacitors
format
sorry about that AndrewT im still new at posting i messed up. my bad.these values are the same?for a 25v300va traffo?for carlos fm supply. p.s AndrewT youre one of my gurus. i might try one of these rectifier boards for fun
sorry about that AndrewT im still new at posting i messed up. my bad.these values are the same?for a 25v300va traffo?for carlos fm supply. p.s AndrewT youre one of my gurus. i might try one of these rectifier boards for fun
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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