Power Amplifier

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For PA speakers you need an amp that can drive difficult load. People usually prefer a high power one, but it doesn't always guarantee a good drive. And power specs is often a lie.

Amplifier with good drive must have paralleled output transistors. Bipolar is better, but there are many cheap/fake bipolars that sound "hard".

If you are after DIY, here at DIYA you can search for "dirty harry" or "NBIP quasi amp" for example. Or find out about "DX amplifier".
 
the speaker is specified as 101dB/W @ 1m
and
127dB @ 1m max.

That implies 200W of input, plus an allowance for compression at high power.
3dB of compression is not unknown, so a 400W amp will allow the speaker to reach 127dB @ 1m.

Buy any 400W into 4ohms PA amplifier.
 
Please dont fall into the trap of trying to get Hi-Fi sound out of rubbish PA speakers, it just doesn't happen. PA speakers are designed to throw sound not to reproduce it accurately.

At a guess they are worth about $50 each.

I wouldn't buy JBL either, BOSE aren't much better. All OK as PA speakers but not real Hi-Fi.
 
Please dont fall into the trap of trying to get Hi-Fi sound out of rubbish PA speakers, it just doesn't happen. PA speakers are designed to throw sound not to reproduce it accurately.

At a guess they are worth about $50 each.

I wouldn't buy JBL either, BOSE aren't much better. All OK as PA speakers but not real Hi-Fi.

Are Hi-Fi speakers are available in 12 inch or 18 inch size speakers
 
Hi Charles,

I am sorry if some members did not rave about your choice of speakers, but they are right in the sense that PA speakers are meant for sound reinforcement, not necessarily accurate high fidelity. They are also right in suggesting to purchase a PA amplifier, which at 400 watt per channel is usually not that expensive as KatieandDad mentions.

Consider a Behringer EPQ900 advertised at AMAZON.COM for only $250. For that amount of money you will hardly buy a power transformer for a class AB amp capable of same 400 watt/ch. Also have a look on e-bay for brand names.
 
Are Hi-Fi speakers are available in 12 inch or 18 inch size speakers

Yes you do find larger "hi-fi" driver units and you may find some bargain, excellent performing vintage loudspeakers on e-bay that will outperform very many modern high-end boxes.

Again there is nothing wrong with your choice of speakers, if they are to your taste in sound then it is as hi-fi as any other hi-fi speaker.

That is what music enjoyment is all about, it is personal and other people's views and tastes are not necessarily the same as yours.

Some might claim one speaker brand to be incredibly accurate and faithful while for the next person it may be plain rubbish.

If you heard those speakers and you like them then buy them, if you are buying cheap speakers out of a catalogue then be careful. A list of specifications for a loudspeaker has absolutely nothing to do with what they sound like.
 
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Hi Charles,

I am sorry if some members did not rave about your choice of speakers, but they are right in the sense that PA speakers are meant for sound reinforcement, not necessarily accurate high fidelity. They are also right in suggesting to purchase a PA amplifier, which at 400 watt per channel is usually not that expensive as KatieandDad mentions.

Consider a Behringer EPQ900 advertised at AMAZON.COM for only $250. For that amount of money you will hardly buy a power transformer for a class AB amp capable of same 400 watt/ch. Also have a look on e-bay for brand names.

But when this amp comes to India the selling price would be doubled

for 400watt amplifier require 50v 10amperes would be sufficient this transformer costs 2000rupees in India thats not equal to 14000rupees
 
A 400W amplifier requires a transformer rated for 400VA to 800VA for good and reliable operation.
If you have two channels of amplifier then you must double the transformer rating.

For 400W into 4r0 you need an output of 56Vpk and 14Apk.
The PSU must be able to meet a transient demand approaching 40Apk to get good performance.
For PA duty you will need a 45+45Vac transformer rated @ ~1500VA (~15Aac to 17Aac) for 400W+400W into 4r+4r.
 
A 400W amplifier requires a transformer rated for 400VA to 800VA for good and reliable operation.
If you have two channels of amplifier then you must double the transformer rating.

For 400W into 4r0 you need an output of 56Vpk and 14Apk.
The PSU must be able to meet a transient demand approaching 40Apk to get good performance.
For PA duty you will need a 45+45Vac transformer rated @ ~1500VA (~15Aac to 17Aac) for 400W+400W into 4r+4r.

Dear Andrew

could you please suggest me an amp to diy
 
Decide what budget you have.
Then decide what you can afford to buy.
The amplifier part will likely only be about 10% of your total cost. You have to work out if you can afford the other 90%.

Buy a secondhand PA amplifier. They were built for PA duty.

I have decided to DIY powerful amp for PA duty for this you have to suggest me which amp to start the process
 
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