I don't recommend canceling capacitors.
But in fact, I tried to cancel the capacitor. There won't be a serious problem.
But I still feel that. There is no need to cancel the capacitor. It won't do any harm.
You can also replace it with a better capacitor.
The biggest problem of switching power supply is. Different switching power supply. The performance varies greatly
But ordinary AC transformer. Regardless of the price, basically the same performance.
So it may have a bad effect. There may be no problem.
It's a bit of a hassle.
If you must use switching power supply. It is better to add 10000 UF capacitor at the output. On the positive and negative power supply.
I'll use a 500VA potted toroidal transformer from Toroidy (their Audio line of transformers) that is: 230VAC primary and 0-48Vac + 0-48Vac secondaries.
I have six of the big caps in the attached picture I'll use(the toy-looking caps next to it are actually standard sized 10000uF/50 snap-in caps lol).
I ordered an L30D module to use with the (unloaded) +/-75Vdc 500W (LLC?, don't remember)
The L30D will drive the two Dayton 15" IB's in parallel in an upscaled version of Linkwitz W-baffle subwoofer.
I have six of the big caps in the attached picture I'll use(the toy-looking caps next to it are actually standard sized 10000uF/50 snap-in caps lol).
I ordered an L30D module to use with the (unloaded) +/-75Vdc 500W (LLC?, don't remember)
The L30D will drive the two Dayton 15" IB's in parallel in an upscaled version of Linkwitz W-baffle subwoofer.
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Thanks
But since I have a toroidal transformer that's 500VA 2x48Vac (that's about 68Vdc) I can use with the L20D modules, and I bought an L30D module to use with the 500W smps that is around +/-75Vdc...I'm pretty much good for now.
I'll use the L20D modules to drive my Infinity's, and the L30D to drive 2x15" open baffle subwoofer.
That gives plenty of headroom, no risk of sub or speakers being starved of power.
Thanks for the tip though
Dummy load (resistor) needed?
I'm getting close the point of testing both a stereo L20D and a mono L30D.
I have a pair of 8ohm resistors mounted on a heatsink (big enough to cool a stereo LM3886 with ease), is it necessary for me to get it out of storage for testing the L20D and L30D?
I'm asking as I know that some class D modules gets destroyed if powered up without any load.
I'm getting close the point of testing both a stereo L20D and a mono L30D.
I have a pair of 8ohm resistors mounted on a heatsink (big enough to cool a stereo LM3886 with ease), is it necessary for me to get it out of storage for testing the L20D and L30D?
I'm asking as I know that some class D modules gets destroyed if powered up without any load.
I've finally gotten around to, slowly, putting a stereo poweramplifier using 2x L20D modules, 500VA 0-48VAC + 0-48VAC transformer, 6x Epcos 4700uF/100V very nice capacitors(20000h at 105C), SST01(softstart from P-A Sjostrom) and two medium size enclosures(I don't have one large enough without heatsinks, and I refuse to use a nice heatsinked enclosure for something not requiring heatsinks).
Well, actually medium size might be a bit generous...anyway, I'll use them one on top of the other with spacers as the capacitors are just a bit too tall.
These enclosures have seen better days, but I plan on covering the fronts and maybe the sides with some nice, dark wood.
The transformer and capacitors are VERY heavy
I'm not sure about using the bare copperwire as shown in the picture, I may go for a multistrand 2,5mm^2(AWG14), the same as the black and red insulated cables connecting to the caps.
I think this amp will sound quite nice when completed, I believe the linear powersupply is more than adequate for this Class D amplifier.
Well, actually medium size might be a bit generous...anyway, I'll use them one on top of the other with spacers as the capacitors are just a bit too tall.
These enclosures have seen better days, but I plan on covering the fronts and maybe the sides with some nice, dark wood.
The transformer and capacitors are VERY heavy
I'm not sure about using the bare copperwire as shown in the picture, I may go for a multistrand 2,5mm^2(AWG14), the same as the black and red insulated cables connecting to the caps.
I think this amp will sound quite nice when completed, I believe the linear powersupply is more than adequate for this Class D amplifier.
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Up and running
Well, it's finally up and running
It's built well, but ugly as sin currently. I will put some nice, oiled, dark wood on the front(s) and sides. Since the capacitors and transformer took up soo much space, I have two identical enclosures...one on top of the other.
The bottom half house the transformer, bridge rectifiers and the capacitors, the top half house the Sjostrom Audio SST01 (I really like this softstart), the L20D boards, the on/off-switch and all connectors.
I still need to tidy up the internal wiring. I went with 0.6mm 99.9% silver wire threaded in to PTFE-tubing, for the input cable. I made four lengths(per channel) of it and braided it.
I haven't really had the time to listen that much, but initial impressions are good. Absolutely no noise or thump when turning the amp on or off, with my ear against a speaker and the volume at 12 o'clock (music paused) there's a barely audible hum. That hum however is so faint that it's most likely the, not for long, rats nest of cables with power cables crossing interconnects...it's ugly.
I blame my backpain for that one, but I just recently found out I'll get some help around the house, so I will get that sorted.
Well, it's finally up and running
It's built well, but ugly as sin currently. I will put some nice, oiled, dark wood on the front(s) and sides. Since the capacitors and transformer took up soo much space, I have two identical enclosures...one on top of the other.
The bottom half house the transformer, bridge rectifiers and the capacitors, the top half house the Sjostrom Audio SST01 (I really like this softstart), the L20D boards, the on/off-switch and all connectors.
I still need to tidy up the internal wiring. I went with 0.6mm 99.9% silver wire threaded in to PTFE-tubing, for the input cable. I made four lengths(per channel) of it and braided it.
I haven't really had the time to listen that much, but initial impressions are good. Absolutely no noise or thump when turning the amp on or off, with my ear against a speaker and the volume at 12 o'clock (music paused) there's a barely audible hum. That hum however is so faint that it's most likely the, not for long, rats nest of cables with power cables crossing interconnects...it's ugly.
I blame my backpain for that one, but I just recently found out I'll get some help around the house, so I will get that sorted.
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Thoughts...after a few weeks listening
Well, I'm floored by the sound quality of these modules(granted, I swapped a few parts...and I'm using a very costly linear power supply).
I sort of knew the amp would deliver power, but the difference this amp made in my system is nothing short of amazing.
The two L20D modules with a rather beefy, linear, supply seem to be the perfect match for my Infinity speakers. It is almost like I've gotten a new pair of speakers tbh.
The amp also, thus far, behaves itself very well...no noise, not even with music paused and my ear against the speaker...absolutely zero thump or other noises when turning it on or off.
Well, I'm floored by the sound quality of these modules(granted, I swapped a few parts...and I'm using a very costly linear power supply).
I sort of knew the amp would deliver power, but the difference this amp made in my system is nothing short of amazing.
The two L20D modules with a rather beefy, linear, supply seem to be the perfect match for my Infinity speakers. It is almost like I've gotten a new pair of speakers tbh.
The amp also, thus far, behaves itself very well...no noise, not even with music paused and my ear against the speaker...absolutely zero thump or other noises when turning it on or off.
Hi,
this is my first post (although I am following the forum from time to time ), so big hello to all users.
I am planning to buy two amp modules for my double sub with 4 Ohm 10" subwoofer spakers - dual mono system. Speakers are 150W / 4Ohm nominal.
I have 2 toroid transformers with 2x45 VAC output (800VA) and 4x10.000uF per channel, so around 2x 63 VDC
I am not looking for a big power, rather a better sound and it has to be compatible with my 63VDC linear PSU.
So, which module do you recommend? L20D, L25D or L30D? And from which actual seller?
It is not clear what the differences are. For instance - why are there 2 versions of L25D? Which is better, black or silver (not because of sinkheat colour, but of the elements which are different)?
Thank you
this is my first post (although I am following the forum from time to time ), so big hello to all users.
I am planning to buy two amp modules for my double sub with 4 Ohm 10" subwoofer spakers - dual mono system. Speakers are 150W / 4Ohm nominal.
I have 2 toroid transformers with 2x45 VAC output (800VA) and 4x10.000uF per channel, so around 2x 63 VDC
I am not looking for a big power, rather a better sound and it has to be compatible with my 63VDC linear PSU.
So, which module do you recommend? L20D, L25D or L30D? And from which actual seller?
It is not clear what the differences are. For instance - why are there 2 versions of L25D? Which is better, black or silver (not because of sinkheat colour, but of the elements which are different)?
| L25D Digital Amplifier Finished Board 250W *2 8 Ohm IRAUDAMP9 IRS2092 IRFB4020 | eBay Output power: 250W 2 8 ohms (+ -70V). Channel Efficiency 90% Single-channel driven, 250W. Residual Noise: 200 μV (22 Hz – 20kHz, AES17 filter Self-oscillating frequency). Total Idle Power Consumption 7W No input signal. www.ebay.com |
| L25D Digital Amplifier Finished Board 200-250W * 2 8 oh IRAUDAMP7 IRS2092 | eBay L25d is the L digital series power amplifier board. Output power: 250W 28 Ω (+ - 70V). Channel Efficiency 90 % Single-channel driven, 250W. Total Idle Power Consumption 7W No input signal. Input sensitivity: 1.6V. www.ebay.com |
Thank you
I would choose L25D if they are still available. L30D have been said to be not as reliable as L15/20/25 modules. But L25D are for 8Ohm speakers, so be careful with your drivers.
You can have trouble if the impedance of the speakers falls very low, much below 4 ohms. This can happen. The amp might switch off or even break down. Besides, the higher frequencies might be louder than the rest of the range. But if you are careful, nothing bad can happen at all. Remember, a speaker protection is a must.
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Yes, I already ordered exactly the same protection module.
Stated minimum impedance of my Peerless XXLS P835016 is 3.119 Ohm at 125Hz so I may have problems...
https://products.peerless-audio.com/transducer/465
But I am planing to cut it at 250-300Hz so HF is not really a problem for me. I will only use L25D for low end up to this frequency.
Stated minimum impedance of my Peerless XXLS P835016 is 3.119 Ohm at 125Hz so I may have problems...
https://products.peerless-audio.com/transducer/465
But I am planing to cut it at 250-300Hz so HF is not really a problem for me. I will only use L25D for low end up to this frequency.
Why don't you obtain another Peerless XXLS and put them in series, two by two, making bigger low-end speakers and raising their impedances to around 8 ohms? That's the ultimate solution. L25Ds will thank you!
Actually, I have two of them but I would like to have 2 mono subs (each with passive radiator). There are some reasons for that, especially ambient ones and acoustic as well...
I will built 2 pieces simmilar to this, I already have all the drivers and just need 2 mono amps for them:
http://www.hardwareanalysis.com/content/article/1699/
So, are there any other D-class modules which will be happy with weak 4 Ohm load and +/- 63V DC PSU?
I will built 2 pieces simmilar to this, I already have all the drivers and just need 2 mono amps for them:
http://www.hardwareanalysis.com/content/article/1699/
So, are there any other D-class modules which will be happy with weak 4 Ohm load and +/- 63V DC PSU?
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