look at wikipedia if you don't yet know what a bridged amp is (never mind if you already do).
if an amp requires a single supply it is most probably bridged.
there are exceptions, but for modern class D amps this is usually true.
you cannot use bridge amps to form another bridge.
I would still recommend that you use two amps and two subwoofer drivers. that way you will get +3 dB from doubling the power and another "free" 3dB from the added diapragm surface. you could use them in force canelling configuration. or you could locate them in different positions to even out room response.
using only one driver with double power will only gain 3 dB. and the bass response will be very VERY different depending on where you are in the room.
also keep in mind:
using a driver with 3dB more sensitiviy gives the same result (or even better because of lower thermal compression) as doubling the power.
putting the subwoofer next to a wall gives (roughly) +6 dB.
I did... The info in the exact wiki page shows that I need the extra logic circuit, which I assume is not present in those amp boards.
I also looked at all kinds of forums and web in general, so there is some info, like for example that if "negatives" share common ground (closed circuit between them) then probably that amp can be bridged.
Don't mix room gains, subwoofer placement and other things into this post. My idea is way simpler: to have more sound for the same EUR
No, not a logic circuit needed.
you need an inverting circuit.
All the amp modules you mentioned have those. But the amps already are bridged, you cannot bridge them once more.
Well, that's exactly what can be done with wall/corner placement.
Don't be too fixated at the watts-number. Try to learn some more about acoustics.
This is exactly what I try to do! This is multi-way software crossover projects and 90% of the time speaker (speakers and probably subwoofer(s)) will be placed in convenient location, such as random place on the floor or on my table.
I have heard from "some" place, maybe here, maybe some other source, that I need more W to drive low frequencies at the same SPL. Is that correct? If so - the whole idea is to avoid buying subwoofer plate amps
You won't read such things here, at least not without several other more important parameters.
Usually bass loudspeaker drivers are the less sensitive ones and most music power is aroound 100-200 Hz (depends on music genre), so you need most power there.
But, as mentioned, it depends much on the sensitivity of your speakers and your desired spl.
What about using higher supply voltage for bass channel?
right. so this is your limiting factor for maximum power: about 15W at 4 ohms bridged. nothing (except maybe a DC converter) can change this.
if you try to find a 2 ohm driver and use PBTL (parallel bridged) amp you may get about 30 W.
but I seriously doubt that it makes much sense to build a 3-way system based on such restricted supply voltage. why not go for a 2-way with a high efficiency low excursion woofer? you don't need the excursion anyway, with low power.
is it a car system?
Audiophonics.fr replied couple hours ago with the same answer as you told: none of those boards are suitable for bridging. They also recommended 3116 based as best value for money.
This is pure practicality... If something goes wrong or I get bored by this project - I just do not want to stick exotic voltages parts so I can re-use amp boards, power supply and so on. 12V is the most popular low voltage standard. It will cost 200+EUR already, which is pretty big money in the recession we are in.
I am sure 6-8 inch woofer + some tweeter is a nice project, if you have ideas with good value for money - just let me know!
Peerless XT25SC90-04 looks ok as cheap beginner's tweeter, does it? For woofer I would like to look at smth paper/paper composite based, because I prefer sound of paper cone speakers. Is there cheaper, but decent RS-180P, RS-225R alternative?
I am not sure if you already have an active x-over or a dsp solution (be prepared for a steep learning curve if you intend to build/use active filters!). if you don't here is just a thought, you could:
I suggest you follow a proven project, such as (just what comes to my mind):
https://www.diyaudio.com/community/...sealed-simple-loudspeaker-build-plans.352046/
As you seem to like dayton rs180:
https://sites.google.com/site/undefinition/floorstanding-speakers/amiga
Or:
https://ampslab-spk.com/projects/
quite cheap (german, eventually use translator):
https://www.donhighend.de/?page_id=5457
Or:
https://www.der-akustische-untergrund.de/speakers/intermediate-projects/winter-blues/
you will find several others, just do an internet search!
- buy one tpa3116 based stereo amp
- buy (if you don't already have it)an adjustable lab supply up to 24V / 5-8 A (provides around 30 W@8ohm or 60 W @4ohm with tpa amp). If you get bored you can still use it as lab supply.
- build a nice cheap passive 2 way speaker.
I suggest you follow a proven project, such as (just what comes to my mind):
https://www.diyaudio.com/community/...sealed-simple-loudspeaker-build-plans.352046/
As you seem to like dayton rs180:
https://sites.google.com/site/undefinition/floorstanding-speakers/amiga
Or:
https://ampslab-spk.com/projects/
quite cheap (german, eventually use translator):
https://www.donhighend.de/?page_id=5457
Or:
https://www.der-akustische-untergrund.de/speakers/intermediate-projects/winter-blues/
you will find several others, just do an internet search!
https://ampslab-spk.com/buy-schematic/
The 3116 is a good option, you can drive it from 12-24V. There are all kinds of cheap and not so cheap matching SMPS around.
Next step in low cost high quality amps is the TDA7498E, which will work 24-36V. Please take care to get the "E" version, as the one without "E" only works with 8 Ohm speaker's.
SMPS are just as cheap. Which SMPS you use depends on how you want to use them. If you build it inside a metal case, you may use an open power supply. Which are dead cheap and better than many will tell you. For 8 channel 7498E including 36V power you can get away with 150€ if you shop smart. Some mentioned outlets are very expensive for 100% the same amp PCB you get on eBay, Amazon or Aliex.
This 7498e gives you realistic peak power of 120W into 4 Ohms and you need not bridge anything, because they are already bridged. For 3 Ohm you can parallel a stereo amp PCB and get 180W.
You will realize that lower power doesn't save you real money, as the most expensive part is building the whole stuff into a nice and save case. For high quality reproduction and using a DSP, some headroom is important, even if in average listening you don't need more than a few Watt.
The 3116 is a good option, you can drive it from 12-24V. There are all kinds of cheap and not so cheap matching SMPS around.
Next step in low cost high quality amps is the TDA7498E, which will work 24-36V. Please take care to get the "E" version, as the one without "E" only works with 8 Ohm speaker's.
SMPS are just as cheap. Which SMPS you use depends on how you want to use them. If you build it inside a metal case, you may use an open power supply. Which are dead cheap and better than many will tell you. For 8 channel 7498E including 36V power you can get away with 150€ if you shop smart. Some mentioned outlets are very expensive for 100% the same amp PCB you get on eBay, Amazon or Aliex.
This 7498e gives you realistic peak power of 120W into 4 Ohms and you need not bridge anything, because they are already bridged. For 3 Ohm you can parallel a stereo amp PCB and get 180W.
You will realize that lower power doesn't save you real money, as the most expensive part is building the whole stuff into a nice and save case. For high quality reproduction and using a DSP, some headroom is important, even if in average listening you don't need more than a few Watt.
I think you can (and should) buy them from @Michael Chua , he is member here.
(edit: just saw @Turbowatch2 already posted a link!)