The Class AB amplifier has about 60% efficiency. That 40% waste depends slightly on the internal resistors, considerably on stability/compensation, but mostly on the load connected, even if the amplifier is idling. With a Chip Amplifier, you'd have to reduce your volume control by more than half, just to stay on the safe side of sorry with a 4 ohm speaker. It would work better to reduce your transformer voltage (to reduce waste consumption HEAT a bit).
Current noise is what happens when you put a heavier load on an op-amp, and it is true of every size op-amps, including chip amplifiers. Parallel amp is the fix. Also, you need a parallel amp so you don't wear out your chip amp, AND, you can use full voltage. SO, build parallel amp with full strength to enjoy a lovely level frequency response, lower noise, more power, and a longer lasting amplifier.
Since I like the type of speakers you're promoting, I've made it easy to do parallel amplifiers:
LM1875 Parallel for 50 watts of high fidelity with a very pretty tone.
TDA7293 parallel kit, modular style (without ballast resistor loss) for 130 watts.
Watts figures are RMS and per each speaker.
Don't forget to size your transformer total watts * 2 = VA, so you can buy transformer amperage necessary for pretty bass.
Stereo+Parallel LM1875, (50+50)*2 = 200VA
Stereo+Parallel TDA7293, (130+130)*2 = 520VA
For running 4 ohm speakers, the transformer gets hefty!
These are higher power amplifiers, so you will want to plan the heatsinks and vents accordingly.
P.S.
If you desire it, I could do an easy solo TDA7294, point to point project, and drop the transformer voltage until the power output meets ST's specs, so with the solo chip, I'd have to know the speaker load before selecting the transformer amperage and voltage. It is approximately a 20+20vac transformer, if you've got a 4 ohm speaker. But, I'd also need to know the DCR because if that is less than 3R by ohmmeter, we'd decrease the transformer to an 18+18vac model. See how using a parallel amp would be better than this?
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Hey guys, sorry to say this but 2 cheap speakers in // are not going to be equal to one good speaker at all unless you get very lucky indeed!
Naturally, it all depends on what you personally consider "good sound" but if you're going to spend time, effort and $s on the "box", then the total speakers aren't going to be "cheap" after all and you can easily end up with an unsatisfactory sounding project.
And to add to the story, the vast majority of the speakers available to the diy market show a "gross misrepresentation" (being polite here!) of the published specs (wow, this is news?!) so the "box" designs based on speaker design programs are just "Sudoku" and won't necessarily result in a good sound, however careful you might be.
But, then again, you might just get lucky - some of those "cheap" guitar speakers aren't too bad for sound if you are careful and don't mind spending a fair bit of time getting them to work okay - it does help if you can find someone to test them and get the basic T/S parameters and get a head-start on your cabinets ...
I mean, it does help if you have some idea of the sort of vehicle that you want before you go to the car dealers and buying 2 cheap "junk" vehicles isn't normally the "best" way to go to get a good result - the "Tim, the Toolman" approach (a TV sit-com program) doesn't work any better for speakers!
Naturally, it all depends on what you personally consider "good sound" but if you're going to spend time, effort and $s on the "box", then the total speakers aren't going to be "cheap" after all and you can easily end up with an unsatisfactory sounding project.
And to add to the story, the vast majority of the speakers available to the diy market show a "gross misrepresentation" (being polite here!) of the published specs (wow, this is news?!) so the "box" designs based on speaker design programs are just "Sudoku" and won't necessarily result in a good sound, however careful you might be.
But, then again, you might just get lucky - some of those "cheap" guitar speakers aren't too bad for sound if you are careful and don't mind spending a fair bit of time getting them to work okay - it does help if you can find someone to test them and get the basic T/S parameters and get a head-start on your cabinets ...
I mean, it does help if you have some idea of the sort of vehicle that you want before you go to the car dealers and buying 2 cheap "junk" vehicles isn't normally the "best" way to go to get a good result - the "Tim, the Toolman" approach (a TV sit-com program) doesn't work any better for speakers!
I'm sorry to report that your statement is not entirely true, and for example, look at this: Project Showcase And notice the high crossover point despite awful woofers. It doesn't take luck--it takes smaller LE figure, and parallel voice coils do that. That project well illustrates that much of the advantage to MTM and other dual woofer systems, is decreasing the LE figure, likewise decreasing the woofer RC, and that means less crossover blur/noise. Other way to say it: That speaker would be horrifying with a solo woofer unless one changed the midrange driver to one capable of a lower crossover point. I happen to own a couple of those woofers, solo it is a very poor quality subwoofer (a nearly useless woofer); but parallel, it is a decent woofer. In this particular case, the difference is dramatic. If given better woofers, the difference would not be dramatic.
P.S.
Personally, when shopping, I avoid woofers that have a high LE figure (necessitates huge RC and its consequences of blur) unless I've got a pretty big size midrange driver to use a very low crossover point. I would agree with you that there's no need to make speaker building more difficult and no need to increase risk. But, it is necessary to point out that paralleled woofers make a few things much easier, especially a nice sounding crossover. In trade for that convenience, I am willing to build a parallel amplifier to properly support the double-woofer speakers.
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Ah, sorry Daniel, I stand corrected - it sounds as tho you can get a reasonable result that way for peanuts - good to know.
It might not be a savings once you see what that sort of design can do for awful woofers, and then it becomes More tempting to try it with good woofers, like this: MiniStatements Oh, very tempting indeed! The Mini-Statement although smaller, offers the rich high resolution bass that the cheaper speaker couldn't do as clearly. Thus, the Mini-Statement with about 25 watts will have lowest bass as loud as the Veritas with 150 watts.
Higher resolution, clearer, bass (with the RS woofers) is simply that much easier to hear. It is surprising.
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actualy the current noise is a very valid mention, on the other side it may not be needed. for a given system it is not sure that the amp will ever be cranked up to full volume at all. The speakers may not be able to handle the power at all. I do not claim it to be a fact, never verifyd it by other means then my personal experience, even so i would think that bass notes have the highest amplitude. I solely base this on :
Equal-loudness contour - Wikipedia, the free encyclopedia
Allso, woofers have an impedance peak at Fs, so near Fs 2 paralelled 8 ohm drivers can still exceed 8 ohm impedance. Given that most likely for reasonable cone sizes for a 2 way design allow that +6 dBL sensitivity gain mentioned previously it may well happen that the amplifier will stay well whitin safe operating area , despite the lower impedance driven.
Or a nother way to look at it, having paralell woofers is quite similar stress for the amplifier than having an EQ drive it with a +3 dBL EQ in the bass region. ( at least i do not see why would it be that mutch different).
While current noise is a very good point, I would rather have some of that than getting close to clipping.
And even if we leave this part of discussion alone, notice that lm1875 can drive 4 ohm load.
surely a paralelled setup has its benefits, but even without that it is still not an overkill to drive a 4 ohm load without problems.
Getting back to topic a bit, i would say that there are better way to make somethig clear than having more power. If higher efficiency drivers are out of budget paralell drivers may still be a valid option given if the designer is able to deal with them. Allso higher efficiency may come from the design of the cabinet too.
Increasing raw power handling and amplifier power is an option too, but even that has its own drawbacks.
Equal-loudness contour - Wikipedia, the free encyclopedia
Allso, woofers have an impedance peak at Fs, so near Fs 2 paralelled 8 ohm drivers can still exceed 8 ohm impedance. Given that most likely for reasonable cone sizes for a 2 way design allow that +6 dBL sensitivity gain mentioned previously it may well happen that the amplifier will stay well whitin safe operating area , despite the lower impedance driven.
Or a nother way to look at it, having paralell woofers is quite similar stress for the amplifier than having an EQ drive it with a +3 dBL EQ in the bass region. ( at least i do not see why would it be that mutch different).
While current noise is a very good point, I would rather have some of that than getting close to clipping.
And even if we leave this part of discussion alone, notice that lm1875 can drive 4 ohm load.
surely a paralelled setup has its benefits, but even without that it is still not an overkill to drive a 4 ohm load without problems.
Getting back to topic a bit, i would say that there are better way to make somethig clear than having more power. If higher efficiency drivers are out of budget paralell drivers may still be a valid option given if the designer is able to deal with them. Allso higher efficiency may come from the design of the cabinet too.
Increasing raw power handling and amplifier power is an option too, but even that has its own drawbacks.
potencialy it can happen at any freqvency i must admit.
prehaps i should have made my personal opinion a bit differently.
prehaps i should have made my personal opinion a bit differently.
Perhaps it is a leftover conniption from having quit smoking; however, I seem to have become annoyed with a different sort of fire hazard. . .
Arbitrarily unexpected load, shifts the amplifier design, risks skewing the compensations further exacerbating the consequences of overload condition, so the excuse of simply turn down the volume is not a guaranteed repair for a double-load error. Generally, we wouldn't want to promote adding house fire capacity to volume knobs via purposefully overloading home-spec 8 ohm amplifiers with car-spec 4 ohm speakers.
So, for your own protection, I ask you to avoid questionable excuses with volume knobs, and instead of a hazard, you can specify amplifiers that handle 4 ohm loads easily.
Test conditions for overload isn't the same thing as handling 4 ohm loads safely for long term use. The two concepts are very much different. And, I still don't like excuses with inbuilt fire hazards because that makes me grumpy. Besides, I already made this mistake and I'm reporting it so you don't have to repeat it.
P.S.
Speakers take a while to build, but making amplifiers is much easier and cheaper in comparison to speakers. So please don't promote risking the speaker due to lack of a couple of dollars and a few minutes more effort at the amplifier. Am I makin sense? Man, I hope so. Also, 6 month long term test proofing of amplifiers is extremely annoying when there's a failure, a redo, and 6 months more testing. Instead of a mess, surely the enhanced durability of a parallel amplifier is a lot more convenient.
P.P.S.
Well, I've done my best to make sense, but in any case, please look at this kit: 2-Channel Loudspeaker Protection KIT (K4700)
Well, although logical at first glance, that statement is not without caveats.
Arbitrarily unexpected load, shifts the amplifier design, risks skewing the compensations further exacerbating the consequences of overload condition, so the excuse of simply turn down the volume is not a guaranteed repair for a double-load error. Generally, we wouldn't want to promote adding house fire capacity to volume knobs via purposefully overloading home-spec 8 ohm amplifiers with car-spec 4 ohm speakers.
So, for your own protection, I ask you to avoid questionable excuses with volume knobs, and instead of a hazard, you can specify amplifiers that handle 4 ohm loads easily.
Using test conditions just because we could? And then a few months later, the documented typical failure mode of a chip amp slowly worn out by overcurrent damage is to suddenly and without warning emit one full rail's worth of DC offset into the speaker. There is some risk of fire.
Test conditions for overload isn't the same thing as handling 4 ohm loads safely for long term use. The two concepts are very much different. And, I still don't like excuses with inbuilt fire hazards because that makes me grumpy. Besides, I already made this mistake and I'm reporting it so you don't have to repeat it.
P.S.
Speakers take a while to build, but making amplifiers is much easier and cheaper in comparison to speakers. So please don't promote risking the speaker due to lack of a couple of dollars and a few minutes more effort at the amplifier. Am I makin sense? Man, I hope so. Also, 6 month long term test proofing of amplifiers is extremely annoying when there's a failure, a redo, and 6 months more testing. Instead of a mess, surely the enhanced durability of a parallel amplifier is a lot more convenient.
P.P.S.
Well, I've done my best to make sense, but in any case, please look at this kit: 2-Channel Loudspeaker Protection KIT (K4700)
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actualy i did mention other solutions too.
You are not going to burn your house with a pot if you limit input voltage, or decrease gain.
in both cases the amplifier will not have to support more output current than with an 8 ohm load.
And even still, an 8 ohm woofer and an EQ of +3 dBL at 100 hz is quite the same load on the amplifier as 2 woofers of those woofers in paralell and no EQ at 100 hz. At 100 hz both represent verry closely the same load. Do You advise everyone who has high EQ settings to not burn theyr house down with say.. a simple click in an EQ software?
where does the fire come from then?
//btw, even the kit linked can go nuts.//
You are not going to burn your house with a pot if you limit input voltage, or decrease gain.
in both cases the amplifier will not have to support more output current than with an 8 ohm load.
And even still, an 8 ohm woofer and an EQ of +3 dBL at 100 hz is quite the same load on the amplifier as 2 woofers of those woofers in paralell and no EQ at 100 hz. At 100 hz both represent verry closely the same load. Do You advise everyone who has high EQ settings to not burn theyr house down with say.. a simple click in an EQ software?
where does the fire come from then?
//btw, even the kit linked can go nuts.//
I understand that you wish to promote your exciting and dynamic 4 ohm speakers. I like them too! I don't understand why you want to drive them with solo chip amplifiers. But, that is doable.
And, yes you can.
LM3886T MyRef design is very stable (super stable runs cooler), and if you also use a CRC power supply, then their specified 22+22 transformer is suitable (although a 20+20 is wiser). The prospect is a bit wasteful, because of LM3886T's internal protection limiting actual output. The good news is that, when running Stable and Cool and on Clean power, the protection system works. LM3886T, TP260, shoulder washer, good ventilation and double size heatsink is recommendable. Current noise is reduced by the external small signal pilot amp feedback loops.
Long term testing passed intact while driving 4 ohms.
The Decibel Dungeon T-network designs are inverting, which increases compensation strength, promotes stability and therefore sounds laid back and runs cool in most cases (do please add the RF filters, zobel, etc. . . to help it further). You're on your own for the fine tuning and choosing a buffer or preamp. However, my subwoofer has LM3886T with a 20+20 transformer and a 4 ohm speaker. It is a cool running Decibel Dungeon inverting design. I've never heard the protection sound off with a screech pop or clunking the mute. The thing runs well; however, despite similar parts count and cost, the MyRef performs clearer for a full bandwidth amp.
Long term testing passed intact while driving 4 ohms.
Note:
Since the inverting and T-network inverting designs run best with a buffer or preamp, it should be possible to re-deploy the preamp as a "pilot amp" simply by connecting some added amount of global negative feedback from speaker to preamp, which is called nesting or composite design. By that same global negative feedback proportion, a pilot amp will decrease current noise, decrease harmonic distortion and level the tone, perhaps approaching the audio quality of the MyRef which also contains a pilot amp at input. I leave this note (about nesting) here for those who wish to reinvent the wheel.
For the above LM3886 examples running a 4 ohm speaker, the metal tab LM3886T (with high speed thermal insulator, a shoulder washer, and a big heatsink) is specified by LM3886's manufacturer, National Semiconductor, due to thermal interface.
My quite different designs for TDA7293/4 do run cool (much different than the datasheet design), because of good filtering and really because I've made most of the choices aimed at cool. It can use a 20+20 transformer if running 4 ohm speakers. Or, it can use a Fairchild Stealth bridge rectifier, a CRC power supply and a 22+22 transformer. Be sure to buy authentic chips from ST. Counterfeit chips don't have functional protections, thus not suited to 4 ohm speakers. The authentic ST part is far more durable.
With lower voltage 4 ohm speaker use, the optimal gain (a very narrow range thanks to miller comp) is sufficient and this is more convenient than using a preamp with higher voltage and 8 ohm speakers. And, when authentic is set up cool and clean, the protections work (on the authentic ST chips). With no gain on the output section, current noise is reduce by the internal small signal pilot amp's feedback loop, IF you've got well done clean power (not the datasheet design).
Long term testing passed intact while driving 4 ohms.
However, there's a catch.
The design is up for revision for improved audio quality, new point to point design and new filtering, and consequently the additional long term test won't be completed until 2013. I won't promote it for 4 ohm speakers until after it has been extensively proofed. I do the testing over the winter when the months of heat output from testing is useful.
Basically, all of the above is push for power design if you use a 4 ohm speaker. But choices exist for doing either poorly or well. Reduced transformer voltage and added current mitigation is a place to start, but also, the amp design really needs fine tuned for cool running. Extra efforts for stability (via added filters And good layout), ventilation (cool air in at bottom, hot air out at top), heatsinking (double size plus double speed thermal interface), and clean power (eliminate extraneous workload) are required for long term success.
However,
Since those key factors (for cool running / stability / filtering for decreasing extraneous workload) are never guaranteed (especially Not with random kits and internet projects), then I'd rather promote a more durable parallel amp instead of push for power design.
And, yes you can.
LM3886T MyRef design is very stable (super stable runs cooler), and if you also use a CRC power supply, then their specified 22+22 transformer is suitable (although a 20+20 is wiser). The prospect is a bit wasteful, because of LM3886T's internal protection limiting actual output. The good news is that, when running Stable and Cool and on Clean power, the protection system works. LM3886T, TP260, shoulder washer, good ventilation and double size heatsink is recommendable. Current noise is reduced by the external small signal pilot amp feedback loops.
Long term testing passed intact while driving 4 ohms.
The Decibel Dungeon T-network designs are inverting, which increases compensation strength, promotes stability and therefore sounds laid back and runs cool in most cases (do please add the RF filters, zobel, etc. . . to help it further). You're on your own for the fine tuning and choosing a buffer or preamp. However, my subwoofer has LM3886T with a 20+20 transformer and a 4 ohm speaker. It is a cool running Decibel Dungeon inverting design. I've never heard the protection sound off with a screech pop or clunking the mute. The thing runs well; however, despite similar parts count and cost, the MyRef performs clearer for a full bandwidth amp.
Long term testing passed intact while driving 4 ohms.
Note:
Since the inverting and T-network inverting designs run best with a buffer or preamp, it should be possible to re-deploy the preamp as a "pilot amp" simply by connecting some added amount of global negative feedback from speaker to preamp, which is called nesting or composite design. By that same global negative feedback proportion, a pilot amp will decrease current noise, decrease harmonic distortion and level the tone, perhaps approaching the audio quality of the MyRef which also contains a pilot amp at input. I leave this note (about nesting) here for those who wish to reinvent the wheel.
For the above LM3886 examples running a 4 ohm speaker, the metal tab LM3886T (with high speed thermal insulator, a shoulder washer, and a big heatsink) is specified by LM3886's manufacturer, National Semiconductor, due to thermal interface.
My quite different designs for TDA7293/4 do run cool (much different than the datasheet design), because of good filtering and really because I've made most of the choices aimed at cool. It can use a 20+20 transformer if running 4 ohm speakers. Or, it can use a Fairchild Stealth bridge rectifier, a CRC power supply and a 22+22 transformer. Be sure to buy authentic chips from ST. Counterfeit chips don't have functional protections, thus not suited to 4 ohm speakers. The authentic ST part is far more durable.
With lower voltage 4 ohm speaker use, the optimal gain (a very narrow range thanks to miller comp) is sufficient and this is more convenient than using a preamp with higher voltage and 8 ohm speakers. And, when authentic is set up cool and clean, the protections work (on the authentic ST chips). With no gain on the output section, current noise is reduce by the internal small signal pilot amp's feedback loop, IF you've got well done clean power (not the datasheet design).
Long term testing passed intact while driving 4 ohms.
However, there's a catch.
The design is up for revision for improved audio quality, new point to point design and new filtering, and consequently the additional long term test won't be completed until 2013. I won't promote it for 4 ohm speakers until after it has been extensively proofed. I do the testing over the winter when the months of heat output from testing is useful.
Basically, all of the above is push for power design if you use a 4 ohm speaker. But choices exist for doing either poorly or well. Reduced transformer voltage and added current mitigation is a place to start, but also, the amp design really needs fine tuned for cool running. Extra efforts for stability (via added filters And good layout), ventilation (cool air in at bottom, hot air out at top), heatsinking (double size plus double speed thermal interface), and clean power (eliminate extraneous workload) are required for long term success.
However,
Since those key factors (for cool running / stability / filtering for decreasing extraneous workload) are never guaranteed (especially Not with random kits and internet projects), then I'd rather promote a more durable parallel amp instead of push for power design.
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I do not want to drive them at all costs with a solo chip.
But, it is an option if someone is on a low budget.
Same for the dual chaepo midbass drivers.
If an example cheapo midbass driver has not so mutch powerhandling (not uncommon at all),
then it is a budget option to paralell 2 of them. Even paralelled it may not consume even the 2/3 of available amplifier current. In wich case there is nothing bad in the setup -as far as for amplifier safety-.
The title says power vs clarity, and the dual midbass solution is just one of the many methoods to have a higher sensitivity for cheap. (in a limited freqvency range, that is.)
And if we talk about cheap, double size powersupply , paralell chips, and double heatsinking and so on are not realy an option.
So where does the fidelity comes from ? it comes from a few allready mentioned point.
Like not even getting close to supply voltage rail, having larger cone area, half Le, and so on..
I just do not want to be seen as a promoter of amplifier overdriving. Having a 4 ohm load does not by necesity owerload a given amplifier. Even f it was designed for 8 ohm loads.
It all depends on the whole setup if it happens or not.
But, it is an option if someone is on a low budget.
Same for the dual chaepo midbass drivers.
If an example cheapo midbass driver has not so mutch powerhandling (not uncommon at all),
then it is a budget option to paralell 2 of them. Even paralelled it may not consume even the 2/3 of available amplifier current. In wich case there is nothing bad in the setup -as far as for amplifier safety-.
The title says power vs clarity, and the dual midbass solution is just one of the many methoods to have a higher sensitivity for cheap. (in a limited freqvency range, that is.)
And if we talk about cheap, double size powersupply , paralell chips, and double heatsinking and so on are not realy an option.
So where does the fidelity comes from ? it comes from a few allready mentioned point.
Like not even getting close to supply voltage rail, having larger cone area, half Le, and so on..
I just do not want to be seen as a promoter of amplifier overdriving. Having a 4 ohm load does not by necesity owerload a given amplifier. Even f it was designed for 8 ohm loads.
It all depends on the whole setup if it happens or not.
Ah, these points are getting really interesting.
Halved LE figure. I love that!
There's a couple of cheats for the amp, and I'd like to mention that the amp board and power board are only a tiny fraction of an amplifier's price. If you add about $12 to the transformer purchase you can generally get an amperage boost, and maybe enough to preserve good bass quality when driving heavier loads. If you add almost any metal parts to the heatsink (such as nice big "L" brackets, and other metal parts both thermal pasted and bolted on), it will boost the heatsink very nicely. Vent under and over also boosts the heatsink. Chips range from $2 to $7, so parallel isn't expensive, but rather it is an inexpensive way to get rid of crossing noise to the benefit of higher quality treble and get rid of current noise to the benefit of higher quality midrange.
So, you can see the picture of a power boost, bass quality boost, a midrange quality boost and a treble quality boost for approximately about $19. Of course a $1,900,000 cost increase is really bad news if you're building 100,000 amplifiers, and there is the reason to avoid shopping retail audio. However, when building 1 DIY amplifier, then the quality versus cost issue is more manageable.
It's not often mentioned, but a builder should consider venting and airflow when preparing a chipamp enclosure the same way current flow is considered in the circuitry.
Yes actualy for a 20 watt amp IC a big chunk of metal and a small fan will be probably well enough heatsinking. And there are ways to "hack" a powersupply too.
It is DIY, so there is only 1 rule... if it statisfies the owner, then its good. -i used to say-
I do know that the methood i mentioned to get few dBL extra loudness is not the best.
But it is still a valid option with all of its drawbacks and what not, if it is well implented it will work.
About the halfed Le , actualy it was not a point i brought up, i just mentioned it from an earlyer post. I did not research if its valid or not. Ain't my t-shirt 😀
It is DIY, so there is only 1 rule... if it statisfies the owner, then its good. -i used to say-
I do know that the methood i mentioned to get few dBL extra loudness is not the best.
But it is still a valid option with all of its drawbacks and what not, if it is well implented it will work.
About the halfed Le , actualy it was not a point i brought up, i just mentioned it from an earlyer post. I did not research if its valid or not. Ain't my t-shirt 😀
The breeze is free and silent if there's a vent below and a vent above. The heat voluntarily going up will also suck cool air into the bottom of the enclosure. It works well to just have the voluntary breeze run over some metal junk--not a slick surface.
Some people do think your proposal is entirely correct.
For example Duntech Soverign works alright with double the impact and half the crossover noise:
An externally hosted image should be here but it was not working when we last tested it.
There's more to it than double-woofers. Also we could notice the size of their amplifiers.
Here on diyaudio.com there's some similar projects as well.
And here's some cost effective high fidelity speakers that can play loud: Speaker Design Works The "Statement" looks like a smaller size Soverign. Those that can play loud with the least distortion also feature a midrange, full range, or wideband speaker to reproduce the vocals, so that vocals can't get scrambled by the woofer excursions when you crank up the power.
Let's look at the RS180 in the Mini Statement speakers.
The higher resolution woofer that is doing FAR more work can also make a bit more reactive load. The current handling caveat is higher than paralleling ordinary woofers. For example, the highly reactive RS180-4 KO's the LM3886 (lots of clunking noises as the chip's protection repeatedly flips the mute).
Compromise that has been removed from the speaker, has ended up in the amplifier
Problem, both double woofer and more reactive requires the highest current capacity (Current Headroom) in order to avoid current noise and/or breakage.
Solutions:
AndrewT's brilliant recommendation is to use a driver chip with parallel output devices, for a discrete build that's almost as easily done as a regular chip amp.
Jeff Rowland's solution, is the triple parallel chip amp; however, AndrewT's solution is more streamlined so that better performance is easier to do.
My bottom dollar cost-effective solution is a simple 2-chip TDA7293 Parallel kit, but it usually needs a preamp.
The Diyaudio.com Team's solution is to put the well marked board for an excellent discrete amp into the diyaudio store, thus changing the effort for a discrete amp into an hour's worth of soldering.
it is very noble thing to .. find real life example that is in agreement with my original point and it shows what a great community diyaudio is. composed of rational and reasonable memebers such as You.Sir.
Thanks for your kind words.
One of these days I'll be doing a speaker design and would definitely appreciate your input.
One of these days I'll be doing a speaker design and would definitely appreciate your input.
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