A little confused

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I don't know which drivers you are planning to, however, I can say that amount of power is not necessary. It may give plenty of headroom but that sort of power is more suited to passive speakers where there are considerable losses in the crossover.

Because the drivers are being driven directly by an individual amp, far less power is required, even for very high volumes. My active three ways are powered by LM3866TFs and there is not ever any want for more power, and that is driven to about 1/3 of their maximum.

The advantages of lesser powered amps are smaller size, lower power dissipation (not always), and lower cost. Anyway, it is your money and how you spend it is up to you. In this case, overspending won't necessarily confer any, if at all, advantages.
 
I should say that I don't want to put you off going active, far from it. I think you will find the benefits immediately obvious and immensely enjoyable.

That said, I believe one of the amp modules requires a split DC supply and the requirements are shown as such, whereas the other needs an AC supply though whether it is centre-tapped isn't clear. You might have to email the vendor. If nothing else, it may also gauge the level of support you may get if you buy.

I control the volume with a pre-amp, using a PGA2310, from which a balanced feed is fed to both speakers. "Smells Like Teen Spirit" can fill the neighbourhood, as can Natalie Merchant. :)
 
Hmmm, I submitted a post and it vanished.

To control volume, for both speakers where all amps and the crossover are housed, I use a pre-amp with a PGA2310. A balanced feed then goes to the speakers. I'm not familiar with other mechanisms but, nonetheless, I think sticking to a central control is the easiest option. If there rae others, I invite other posters to provide information, for us both.
 
@Absconditus

Can you give me a breakdown of your system? It sounds like you have done what I have in mind. I am open to using several lower powered amps for each driver but am inexperienced.
I am not sure if I should utilize multiple power supplies at that point (switching or linear), need a rectifier or attenuator, etc.
 
I can't give any recommendations for those sort of amps, having not ever used them. There are threads on this forum about such amps, eg the Wire, of which many posters speak highly. There is plenty of information, including building them.

My system is based on advice from a former member of this forum and, for which, I thank him. It uses the chip amp, LM3886TF, for all drivers and in bridge mode for the woofer. I use a 25-0-25 toroidal transformer that gives +-35V and which also allows a +-15V supply for the op-amps in the crossovers and balanced signal driver for the bridged amps.

My system is a three way and I have ever found that volume is lacking. One thing that many don't seem to realise is that an active system can be at ridiculously high levels but does not appear to be that loud because the music is not distorted; it is just louder, as my neighbour in the next street can attest. (Sorry Danny. :) )

The LM3886 gives about 60W RMS into 8 ohms and bridged gives about 100W RMS. You will NEVER get to use even close to half of that power unless you need to use them for very, very large rooms (or for rave parties where there can be chemically induced deafness). The advantage of them is the small PCB size for the output, particularly when all of the electronics are housed in the speaker cabinet.

I was recommended to use Rod Elliott's PCBs (ESP Sound Products)and I am grateful for that advice. They are the P19 and are small, easy to use and, from my experience, totally reliable. I also use the P05 and P33 boards and have not encoutered any problems at all.

If you need more information, I am happy to give it. Please be specific in what you want though?
 
@Absconditus

You are the best. I appreciate all of the responses.

To be completely honest, I am having trouble being specific. I have a handful of Klipsch replacement cerametallic woofers laying around that I am itching to use. I hooked a 3" up to a Dayton Audio T-amp and was not completely satisfied with the clarity. I have always preferred a forward sounding speaker so the high end is going to be most important in my amp consideration. I can't seem to decide between AB/chip/mosfet as a beginner - I may need to take an electronics engineering course :). If I could find a good mosfet kit I would buy it in a heartbeat but the kits I do find are a bit undocumented (not good for a first-timer).

The chip amp I was considering is here: DIY Chip Amplifier Kits, PCB's, Components and Information.

My main concern is that the final configuration will not be (tweeter, 3" woofer, 5.25", 8", and 12") powered properly. I will probably pick up a class D for the 12 but don't know how to properly power the rest (wouldn't I need at least 2 of the aformentioned chipamp for the rest of the set-up?).

I am looking forward to posting some pictures once this is rolling.
 
I am confused by your seeming choice of drivers, or, to be precise, your LACK of choice of specific drivers. While you have nominated four sizes that will work well together such as in Lenard Audio, Sarabande, the nomination of a 3" woofer as a fifth driver is what I don't understand.

I believe you should take a step back and decide which drivers you want to use, before making any judgements about power requirements. Your choices will be probably be guided by what type of music you will use them for, whether they will also be used for HT, costs (as always), expectations of fidelity performance and size of enclosure/s.

The primary consideration in the initial phase is, I believe, how big a box you (or your wife if you have that important factor to consider) are prepared to consider. As you may be aware, different woofers have different size needs and also whether it is vented or sealed. I suggest you work out which woofer you want to use and go from there.

A woofer with an efficiency from about 87 to 90 db/W can be driven to the point of deafening with the amplifier to which you've linked; even more so if it is bridged. In fact, that is what I would suggest because you will only need one transformer and power supply and, therefore, save space.
 
Not at all. I was please to see the Sarabandes - I was not aware there was a company specializing in active speakers. The fact that they use so many separate amps is even better. I have been stuck on the idea since I demoed a pair of Martin Logans although I am not expecting to get that type of sound. Do you have this brand in Australia? Another interesting active speaker I discovered was at an art gallery - it was a bench designed like a suspension bridge with two 8' columns (we love imperial here). They were array speakers with drivers running up the entire height. The idea was to place them in a public area so someone could simply plug in. I am hoping to reproduce this for my home some day.

My inclusion of the 3" woofer may come from defective logic - I was led to believe that different sizes are better at handling different ranges. My inclusion of woofers will be decided once I have the amp(s) built - I intend to map them so I can filter properly.

My concern about using a single power supply is that the amplifiers will suffer from sporadic power dips. I will certainly need to come up with my own power supply if the amps are wired in parallel.

I think the wife will just need to learn to love it :)
 
Do you have this brand in Australia?
I know this has surprised many of the Americans I have spoken to, but yes, Australia does get the normal range of products available to Western democracies. :) (D@mn! Where is my rifle? There is a kangaroo outside kicking my car! Just joking, this doesn't happen and Australians aren't allowed to own firearms unless they have a very good reason and a licence.)

My inclusion of the 3" woofer may come from defective logic - I was led to believe that different sizes are better at handling different ranges.
They are, however, the driver must be fit for the purpose for which it is intended. Unless the 3" woofer has a frequency range which is usable about that of, say, a 4" to 6" mid-range, then it is not suitable for the purpose. Anyway, going more than four way for an active speaker is inviting excessive complexity for no tangible gain, with the real prospect of impairing the performance.

My inclusion of woofers will be decided once I have the amp(s) built - I intend to map them so I can filter properly.
This is where I think your logic may also be awry. You should start from the first point of a project, not in the middle and then go back to square one. As I suggested, the first point is choosing your drivers, starting with the woofer. You should map out what frequency ranges you want the drivers to cover and the Sarabandes provide good guidance on this. You will then come back to square one; the woofer.
My concern about using a single power supply is that the amplifiers will suffer from sporadic power dips. I will certainly need to come up with my own power supply if the amps are wired in parallel.
I am not sure if I should utilize multiple power supplies at that point (switching or linear), need a rectifier or attenuator, etc.
As I said, my speakers have enough volume, with normal sensitivity drivers (around 87 -88dB/W), for neighbours in the next street to hear, and this from one 160VA toroidal transformer per box which supplies the amps as well as the low level crossover and balanced driver, speaker protectors too. Using a 300VA, or even a 500VA transformer, will NOT leave you short of power. There will be more than enough to permanently damage your hearing very, very quickly.
 
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I have decided to try to build the Honey Badger amp but not for the namesake :)
I am looking at the parts listing and I cannot seem to find some transistors to match the collector-emitter saturation voltage. All other specs match. This build just got way more annoying.

Side Note: Martin Logans are made in the US and I didn't know if they went global

Aren't allowed to own firearms? That's just absurd.
 
Sorry, I've been busy.

There are other sites, I'm sure. Australia has three or four reputable sites, two of which mirror the stores situated around the country. I'd try those first, as well as those mentioned by you. I've had success with eBay, others have not so that it is up to you.

(Answer to Side Note: Yes, I know where MartinLogan's are made. As I said, Australia is one of the first-world democracies that receives nearly everything the rest of the world does. It was a joke about the kangaroos. (They have been known to kill dogs and people so they aren't all cuddly little creatures.)
Australia tightened up gun controls after we had a massacre 16 years ago, in which 35 people were killed. Port Arthur massacre (Australia) - Wikipedia, the free encyclopedia The government decided to buy back guns, tighten controls and make this country safer. There was very little dissent and the problem with guns reduced considerably. Aussies don't have the OK Corral type mindset. We don't think the person with the fastest draw is always the good guy and all the people in white hats will ride away into the sunset, safe in the knowledge the guys in the black hats are dead and the world is safe.)

I am still amused at your choice of amplifier, even though I understand it is a very good design. The building of an active speaker is definitely not for the faint-of-heart. It is a matter of making choices that make the build achievable and with a good outcome, without it becoming a nightmare. You sound as if the turn down the latter path might not be far away. That is why I chose chip amps, as do many others.

Good luck, or is that, good decisions?
 
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