Hi BRN. I bought a couple of these for a budget class D project a while back and still hadn't used them.
UPC1237 Dual Channel Speaker Protection Circuit Board DC 12-24V Boot Mute Delay | eBay
Thought I may as well give one a try finally. It's not perfect. There is still a small pop, but it's no where near the cone excursion I had before. I still need to measure DC at switch on to see when the relay trips. No too worried about it though. There are a few different boards on eBay. I've also been eyeing the diyAudio store boards. I need to read up on those.
I have the exact same one, I think there is a thread discussion how to mod it, actually I think it may be my thread even
you can change the RC values to get a longer delay. It is 3sec but maybe 5 is needed? Many folks use this one and they suggest changing the critical capmom time delay to a polyfilm to ensure reliability.I have the exact same one, I think there is a thread discussion how to mod it, actually I think it may be my thread even
Please, first try to do an A/B test so you have some idea how much it degrades the sound in case...
If too much involvement just not worth to modify etc, you may have to look for other solution.
The cheap relays may be an issue - but I think a quality OMRON can be exchanged easily. I have not hooked up to mine yet so can't say. The big cone excursion is handled by my speaker ok so for me, not worth the potential degradation in sound with a relay contact. SS MOSFET relays are the way to go as they handle huge currents. Several designs floating around.
In my case the el cheapo delay/protect board is temporary until I can source/build something better. I couldn't, in good conscience, keep subjecting my drivers to 12.5vdc every time I switched on the amplifier.
I know pcgab used the diyAudio soft start board in his ALPHA 20 build back in March. Any other impressions on the soft start board Gable? Did you end up using the speaker protection board as well?
I know pcgab used the diyAudio soft start board in his ALPHA 20 build back in March. Any other impressions on the soft start board Gable? Did you end up using the speaker protection board as well?
Juntuin,
Brilliant work...... I love it!
This will consume a lot of electricity, but at least in Finland you can warm the room very nicely. I have a 1Kw electric heater sitting 30cms from my seat as I sit at my PC in cold southern Australia; maybe I should do a BB too, I have the pcbs and the mosfets!
Congratulations, high quality assembly,
Hugh
Brilliant work...... I love it!
This will consume a lot of electricity, but at least in Finland you can warm the room very nicely. I have a 1Kw electric heater sitting 30cms from my seat as I sit at my PC in cold southern Australia; maybe I should do a BB too, I have the pcbs and the mosfets!
Congratulations, high quality assembly,
Hugh
Vunce, any listening impressions Alpha20 vs B.B. ?
Mine are not so ready yet
Hi Juntuin,
Really cool idea for the BB!! I’m also thinking about trying those caps
I’ve been playing around with different power supply configurations for the BB so I haven’t really “critically listened” yet. I’m going to try a different capMx again, (mrevil/PMI), just waiting on some parts.
About my ALPHA20, it’s been used 8-10 hours daily since it’s re-birth a few months ago. No hiccups what so ever! Sounds fantastic and no temperature issues even though it’s summertime now.
Cheers
Thank you guys, you are too nice
Just like X said, monoblocks, 2 fans per case. It's really time consuming to build like this, but I have a good feeling what will become!
Wtl, those caps seems really nice compared their cheap price, thanks for tipping out those!
Hugh, B.B. will be really nice at winter, you are right about that! Fans will nicely spread warm air through the room. Maybe you really should build one too
Vunce, good to hear that things are still rolling pleaae report when you get some more progress. My Alpha20 has been running quite many hours also.
Just like X said, monoblocks, 2 fans per case. It's really time consuming to build like this, but I have a good feeling what will become!
Wtl, those caps seems really nice compared their cheap price, thanks for tipping out those!
Hugh, B.B. will be really nice at winter, you are right about that! Fans will nicely spread warm air through the room. Maybe you really should build one too
Vunce, good to hear that things are still rolling
pleaae report when you get some more progress. My Alpha20 has been running quite many hours also.
Maybe as a additional heater then
. Don't know anything about heating with electricity, rarely used in here.Those Wtl's findings are Kemet 15000uF 63v from Mouser
Hi Guys
Thought I might share this amp that I’d build like 18 yrs ago.
It’s house in a PC case which is internally reinforce with 2 mm alu plates cut to size & glued to the PC shell using contact adhesive. Advantage, kills ressonance.
Hope it is useful to some of you guys
Cheers
Thought I might share this amp that I’d build like 18 yrs ago.
It’s house in a PC case which is internally reinforce with 2 mm alu plates cut to size & glued to the PC shell using contact adhesive. Advantage, kills ressonance.
Hope it is useful to some of you guys
Cheers
Attachments
Here in Finland we use sauna, and at winter times we have heaters in our garage / to feel comfy doing repairs cars/ mechanical steel woodwork requires heat too.Maybe as a additional heater then
Those Wtl's findings are Kemet 15000uF 63v from Mouser
At late nights in autumn we use heaters to sit and talk after sauna.
Good idea to replace to heat resistors
with a class amps for winter to warm up the entire house.
For true a class fanatics.
Tonza, I don't have even garage to warm up
If there is 5mm air gap between capacitor poles and aluminium case cover, is that enough? I won't build anything where is risk of getting shocked, that's why asking. Should I add some thin cover of non-conductive material between alu cover and capacitor poles??
If there is 5mm air gap between capacitor poles and aluminium case cover, is that enough? I won't build anything where is risk of getting shocked, that's why asking. Should I add some thin cover of non-conductive material between alu cover and capacitor poles??
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