Yes, that's right. The amp boards I was mentioning are quite that power range - their power is at 10% THD, so a 500W amp quickly goes down to 330-400W at 1%THD depending on the board, chipset and voltages. I thought I already wrote that, maybe I wasn't clear enough. These amps reach both of these power figures usually at the max voltage and I already suggested lower voltage because of reliability and lower temperatures (usually equals fan noise). So my suggestion for these boards still stand. They are really cheap, how much you'll spend for the complete amp depends on the case, PS etc. but since you want to build one case for everything, it will be much cheaper to do that part too.
No, a bridgeable amp does not help you. Bridging combines two (or more, depending on the amp) channes to one. Parallel bridging (PBTL) is the same as giving each driver it's own channel, no difference, no matter how you wire your two drivers. You don't get more voltage and no more current per driver.
Serial bridging doesn't work for most class D amps or they are already bridged (PBTL usually) and does not help either in this case. Why? You are doubling the voltage (logically, they are in series) but you are not doubling the current. The power is only doubled because the amp behaves like it sees halve the impedance (it halves the damping factor too btw) and they can output more, the power which it is able to deliver at the lower impedance. That means, the amps minimum impedance is doubled or in other words, the same load can be (or more likely: WILL be) too low. So, if you connect them parallel, the impedance will be way too low. If you connect them in series to compensate for the too low impedance, you will still only get the halved of the bridged power - which is the same power each driver will get if it gets its own channel.
And to answer the question (which most likely just arose): Why the heck then bridging at all? It's easy: To use the maximum possible power of an amplifier.
Parallel bridging (PBTL): Doubles the current. Used to drive low impedance drivers.
(Serial) bridging (BTL): Doubles the voltage. Used if the amp can deliver much more power but only at lower impedances as the intended load.
Both reduce the reliability, if one of the channels kicks the bucket, the sound stops, unlike one channel each driver. Bridging is highly dependent on the impedance.
I think that's a good idea. If you didn't know, Sure renamed itself lately, the new name is Wondom.
im not sure if we are understanding each other very well.
i was suggesting getting (for example) the amp i linked to previously.. 200wpc to two subs.
fine for my needs.
if i need to run the subs harder in the future (if i get more powerful satellites) i can run that same amp bridged, providing 700w mono into 4 ohm, with similar distortion levels (if specs are accurate) . i would then add another identical amp, giving me a stereo 700 wpc amp for my two subs.
benefit is i dont need to replace original sub amp if/when i upgrade satellites.
i was suggesting getting (for example) the amp i linked to previously.. 200wpc to two subs.
fine for my needs.
if i need to run the subs harder in the future (if i get more powerful satellites) i can run that same amp bridged, providing 700w mono into 4 ohm, with similar distortion levels (if specs are accurate) . i would then add another identical amp, giving me a stereo 700 wpc amp for my two subs.
benefit is i dont need to replace original sub amp if/when i upgrade satellites.
We seem not to understand each other. Firstly, you can't run these drivers both at one channel with 4 Ohm, that's not a possible impedance you can get with 2x4 Ohm or 2x1 Ohm. On each channel one driver is 4 Ohm and 200W per channel. That makes 400W.
Now you bridge it but you cannot go for 4 Ohm. So you have to wire them in series and get 8 Ohm. On 8 ohm bridged you get 400W and have only one channel then. So it's the same power, you did not gain anything but lose reliability.
Edit: These IRS2092 are quite good for subs but for tops/sat other amps are a bit better.
Edit2: To be clear: The amp does NOT run on 4 Ohm bridged, it becomes much too hot and the current is too high. They are not specified for 2 Ohm so bridged 4 Ohm isn't possible either.
Edit3: You actually can run 2 Ohm but you have to reduce the voltage - which equals in lower power.
Now you bridge it but you cannot go for 4 Ohm. So you have to wire them in series and get 8 Ohm. On 8 ohm bridged you get 400W and have only one channel then. So it's the same power, you did not gain anything but lose reliability.
Edit: These IRS2092 are quite good for subs but for tops/sat other amps are a bit better.
Edit2: To be clear: The amp does NOT run on 4 Ohm bridged, it becomes much too hot and the current is too high. They are not specified for 2 Ohm so bridged 4 Ohm isn't possible either.
Edit3: You actually can run 2 Ohm but you have to reduce the voltage - which equals in lower power.
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yep. definitely misunderstanding..
if i run this amp bridged mode, it can do 700+w into 4 ohms, with 0.1 thd. as per the spec sheet.
i have 2, 4 ohm speakers.
i will currently run one amp in stereo mode, with 200w going to each 4 ohm sub
if i need more power later i can *buy another of these amps* and run both in bridge mode, giving me effectively a stereo amplifier that can do 700w into 4 ohm per channel.
i then run *one* sub from EACH amp. this means 4 ohm load per bridged amp, and unless im missing something major, a lot more power to each sub.
i have done just this setup in the past when upgrading a car system.. keeping the old amp, buying a second identical, and putting both in bridge mode to keep overall stereo operation. gives more power without throwing away original amp and psu.
edit: obviously that cooling must be sufficient ( i plan on using a case with large external heatsink, and connecting the amp to that with a custom metal bracket, replacing current heatsink) and so must the power supply.
i have decided on the 600 watt smps psu from the same manufacturer. it will do 800w peak, so should be sufficient even using this bridged, unless i really , really push it to the limit (not going to happen)
if i run this amp bridged mode, it can do 700+w into 4 ohms, with 0.1 thd. as per the spec sheet.
i have 2, 4 ohm speakers.
i will currently run one amp in stereo mode, with 200w going to each 4 ohm sub
if i need more power later i can *buy another of these amps* and run both in bridge mode, giving me effectively a stereo amplifier that can do 700w into 4 ohm per channel.
i then run *one* sub from EACH amp. this means 4 ohm load per bridged amp, and unless im missing something major, a lot more power to each sub.
i have done just this setup in the past when upgrading a car system.. keeping the old amp, buying a second identical, and putting both in bridge mode to keep overall stereo operation. gives more power without throwing away original amp and psu.
edit: obviously that cooling must be sufficient ( i plan on using a case with large external heatsink, and connecting the amp to that with a custom metal bracket, replacing current heatsink) and so must the power supply.
i have decided on the 600 watt smps psu from the same manufacturer. it will do 800w peak, so should be sufficient even using this bridged, unless i really , really push it to the limit (not going to happen)
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That is plain wrong. They don't even bother to state the power on 2 Ohm each channel because that doesn't run stable. These are practically the same as the Sure and these are rated at a minimum of 3,5 Ohm. They even use the same FETs.
I can only repeat, these amps do not run on 2 Ohm or 4 Ohm bridged. Either you reduce the voltage to do so (and reduce the power with it) or it won't work for long. If you want to run bridged, you have to go for 6-8 Ohm load or go for another amplifier for these drivers.
Yes, that works. If the amp can handle the lower impedance. This one can not. Not every amp is the same! It's the same sane logic as saying that Porsche runs bi-turbo, that will work with my fiat 500 fine too. These car amps are indeed built to work with the low impedances. But there is a lot more to it than just reading the specs and plugging it together.
No, that doesn't help. Well, yes, it does help but your amp still does not work for long with it, the FETs have a current limit, no matter how much cooling you throw at it. Yes, you probably can boost that Fiat to 700 horses but more than a dozend runs on the dragstrip and then you have to sweep up all the bits because it has decided it have had enough.
BTW: These amps do not have a disconnecting relay. If the PS isn't switched off by the amp and it doesn't have a quick-disconnect pin or the IRS2092s protection does not work as intended, a fault of one of the FETs will give you the full DC on the output, they have nothing between the rails and the output other than the output inductance.
I thought you wanted to put two of the amps on it?! No amp got 100% efficiency. Each got a maximum power consumption of 478W which equals 956W. Okay, I see, there's nothing left to say for me. I wish you good luck with your project.
im sorry i didnt mean to annoy you..
I was simply reading the provided pdf from the creator of the amp, which clearly states it can do bridged at 4 ohms. if this is not the case i apologise for taking the amp documentation from a respected supplier at face value.
wrt the psu, i would obviously use two psus if i used 2 amps. no point in getting a 1kw+ psu if i only intend to use one amp initially.
regarding the output relay, this is something of which i know nothing. Im obviously looking for an amp which provides decent speaker protection. if experts such as yourself consider this a bad designed amp or requiring an extra relay output board, i will of course consider it.
in the end, i started this thread, simply looking for advice on a good diy class d or t amp which will work well in my situation. ideally with a little headroom in case i need to run the subs harder in the future. thats all!
we seem to be getting lost in discussions about wether specs are to be trusted. and you seem to be getting annoyed that i am basing my suggestions on the published capabilities of an amp of which i have no direct experience.
it seems you have quite a critical view of both the drivers ive chosen (ive never seen a critical word written about these drivers anywhere, apart from being power hungry. 5 star reviews all round. nobody else in my extensive googling before purchase has ever said they are "slow" or bad at higher sub frequencies, id be interested to see some links discussing this)
-and my suggestions on how to proceed ( based solely on published amp capabilities which i dont know enough to question - i can solder, but ive no experience in amp design, theory, or realistic capabilities of particular components..)
hence the questions.
I was simply reading the provided pdf from the creator of the amp, which clearly states it can do bridged at 4 ohms. if this is not the case i apologise for taking the amp documentation from a respected supplier at face value.
wrt the psu, i would obviously use two psus if i used 2 amps. no point in getting a 1kw+ psu if i only intend to use one amp initially.
regarding the output relay, this is something of which i know nothing. Im obviously looking for an amp which provides decent speaker protection. if experts such as yourself consider this a bad designed amp or requiring an extra relay output board, i will of course consider it.
in the end, i started this thread, simply looking for advice on a good diy class d or t amp which will work well in my situation. ideally with a little headroom in case i need to run the subs harder in the future. thats all!
we seem to be getting lost in discussions about wether specs are to be trusted. and you seem to be getting annoyed that i am basing my suggestions on the published capabilities of an amp of which i have no direct experience.
it seems you have quite a critical view of both the drivers ive chosen (ive never seen a critical word written about these drivers anywhere, apart from being power hungry. 5 star reviews all round. nobody else in my extensive googling before purchase has ever said they are "slow" or bad at higher sub frequencies, id be interested to see some links discussing this)
-and my suggestions on how to proceed ( based solely on published amp capabilities which i dont know enough to question - i can solder, but ive no experience in amp design, theory, or realistic capabilities of particular components..)
hence the questions.
If the amps are used within their actual specs, it works reasonable. There are IRS2092 amps out there which do have a relay (the L15D pro i.e.) but nothing is really really safe - you can destroy anything with enough force.
Some ppl believe anything as soon as it's written on some page. I'm annoyed because I repeadedly told it, explained and described it to you and you still insist that's wrong. If you know it all and that can't be, why ask then anyway?
Yes, I do. But I can differentiate between my own preferences and taste and actual problems and issues. So why differs my opinion from the happy buyers? These are CAR subwoofers. The next door farmer is happy with his Deutz and I know so many who are. That's a completely different field, for cars they need much higher spls, theres noise from the engine, it's often used for show purposes, you've got a pressure chamber enviroment in the car and huge steady power supply (well, at least if you're doing it right) and huge power amps. Generally much higher listening levels. You need as-small-as-possible enclosures for cars. Parameters for small boxes can only be achieved by using huge moving mass and concrete-stiff suspension and huge surrounds with high damping. That in turn let's the mechanical losses go through the roof. That also leads to very low spl (dB/1W (not 2.83V!)) and very high power requirements which can only be realized with very low impedances without going to very high voltages. The drivers don't sound very good or precise at low levels because the initial force to overcome that, low resolution is the result, they only 'wake up' at higher levels (exactly the opposite from your BBs, that's also a reason why I think that's not a good combination). And that's not an opinion, that has been measured (mainly Klippel measurement but also distortion, impulse response and decay). Always better: More cone surface, less excursion. You want to stay at the daytons, I respect your decision and you asked for an amp, not about the speakers.
Okay, suggestions:
- Go for your intended amp. That's fine as long as you don't go for low impedances.
- Same goes for the DIY amps I suggested, no difference there, they are all very close there anyway.
- Get one of the PA amps. They provide much better protection, case, re-sell value, not much more expensive (if at all).
- Get subs with higher impedance if you want to go for bridged drive.
- The BB aren't party animals. Probably think about bigger main speakers and use the daytons as kinda infras, low crossed over, if you want to keep them. Much better fit and the daytons can deliver that.
- Sound reproduction is all about compromises, find the one which fits your needs. Get a general concept on what spl you want/need, how low it has to really go and what for you're using it. Check realism of requirements.
- Stop buying for max specs, start buying for purpose. Sound reproduction is all about compromises, find the one which fits your needs.
I think it's really all said now.
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