I just like to know if I can use the Arcam Delta 290 amplifier in bridge mode (stereo to one mono). Let me know.😕
I don't know anything about the Delta 290, so I can just comment in general. The biggest concern is the current capability of the amp. Remember that bridging has the effect of halving the load impedance. If the amp cannot drive a 2 ohm load in stereo, it cannot drive a 4 ohm load in bridged mono. An 8 ohm load _should be OK.
You will need to add some sort of bridging adapter if the Delta 290 does not have one. This page shows how it is done:
Bridging Adapter For Power Amps
You will need to add some sort of bridging adapter if the Delta 290 does not have one. This page shows how it is done:
Bridging Adapter For Power Amps
you can put the balance 100% on left or right side and the amp will almost double the power , no need to change anything , this means with 2 amps you can have 280w rms for each channel at 4ohms or 150wrms at 8ohms.
one thing you can and should improve are the two big power supply capacitors ( in the middle of the pcb ) 10.000uf 65v is enough.
there´s a switch on the left side of the pcb that skips the preamp section of the amp ( the preamp section of this amp has poor quality).
If you want you can change the opamps , but it´s a lot of work for a little result
one thing you can and should improve are the two big power supply capacitors ( in the middle of the pcb ) 10.000uf 65v is enough.
there´s a switch on the left side of the pcb that skips the preamp section of the amp ( the preamp section of this amp has poor quality).
If you want you can change the opamps , but it´s a lot of work for a little result
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Agree with comments by Ingenius. The Arcam 290 has only a single pair of MOSFETs (latest version used TOP3 IRFP 240/9240). If you intend to drive 4R loads in bridge mode, the performance will be very anaemic and you certainly won't get anywhere near the expected power increase using 4R speakers before something fails or it shuts down. No amount of capacitance will fix this fundamental problem.
I guess you can bridge any stereo amplifier but unless it has at least 2 pairs of Mosfets in the output stage and a substantial power transformer rated for the higher current, it's a waste of time and likely quite a bit money with 4R speakers, considering the damage you can do, overdriving small amps. A parallel array rather than bridge (if feasible) would be more useful. You only have to look inside typical AB automotive power amplifiers to get the picture of how many Mosfet devices are needed to drive impedances of 4R and less in bridge mode.
For the small potential gain, I would use the amplifiers as they are or look for something more suitable.
I guess you can bridge any stereo amplifier but unless it has at least 2 pairs of Mosfets in the output stage and a substantial power transformer rated for the higher current, it's a waste of time and likely quite a bit money with 4R speakers, considering the damage you can do, overdriving small amps. A parallel array rather than bridge (if feasible) would be more useful. You only have to look inside typical AB automotive power amplifiers to get the picture of how many Mosfet devices are needed to drive impedances of 4R and less in bridge mode.
For the small potential gain, I would use the amplifiers as they are or look for something more suitable.
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According to Bob Cordell, IRFP240/9240 and a few other similar types are among the few available V-Mosfets suitable for low distortion, linear operation.
I know that other designers are comfortable using switching types like even trenchfets but I wouldn't say they are better and the gate threshold voltages are not necessarily compatible so modifications and tests would likely be needed.
I doubt there would be a drop-in replacement that was an improvement (assuming you mean more power, low distortion?) and modifying the amplifier to suit other types may not be easy.
However, I haven't tried substituting these popular IRFP types and perhaps others have a better idea of what is appropriate and readily available.
A quick look at Fairchild QFETs such as FQA28N15, suggested for audio and also in TO3P packages, says you have other options but for more power into 2R, you really need more output devices and heatsinking.
I know that other designers are comfortable using switching types like even trenchfets but I wouldn't say they are better and the gate threshold voltages are not necessarily compatible so modifications and tests would likely be needed.
I doubt there would be a drop-in replacement that was an improvement (assuming you mean more power, low distortion?) and modifying the amplifier to suit other types may not be easy.
However, I haven't tried substituting these popular IRFP types and perhaps others have a better idea of what is appropriate and readily available.
A quick look at Fairchild QFETs such as FQA28N15, suggested for audio and also in TO3P packages, says you have other options but for more power into 2R, you really need more output devices and heatsinking.
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