What amp for my subs?

[paulspencer]

I have two AV12 subs with crazy excursion (46mm p-p) when there is plenty of power to throw at them (500 watts into 4 ohms) and all my simulations show that it actually needs that kind of power to move to xmax, unlike others drivers like the Peerless XLS and Shiva which can reach their limits with 100 or 200 watts, depending on the box.

Here it is:

My subs

This is a problem as it's expensive to get this much power into 2 subs. I'd like some suggestions on how to do it on a budget. It seems like whatever I do, I'm likely to have to spend AUD $800 if I:

- get plate amps or
- get a PA amp like the Behrringer Europower or a 2ndhand Crest (or was it crest) ... both costing about AUD $800
- build from a kit (either aussie amps or ESP)

Any / all suggestions welcome!

[johninCR]

One cheap alternative would be to use a car amp and a big 12 volt power supply. Be sure that you outlet can handle the amperage you need regardless of what route you go.

[Kittle]

one suggestion for you to try...

1st off im assuming you have something built.

simply this - use whatever amp you have on hand and listen to what your sub puts out under normal listening conditions.

Reason I say this is I got a 300w plate amp for my sub, and the driver (NHT 1259) is SO LOUD that I cant turn the amp up over 1/4 of the way or my sub overpowers everything else.

If you have nicely efficent drivers you dont need a mongo amp.

so you may be able to get by with a 2 channel 200w amp....

[paulspencer]

No question about it ... 500 watts and no less!
John at Stryke says this is what you need for the AV12 and my experience confirms this. My NAD 2200 bridged into 8 ohms (both subs hooked up in series) has 400 watts rms and it wasn't enough. I tried different configuations for the amp and at one time it went into overload and shut down before the drivers were moving to half their xmax. I have nothing that is working to use for these subs at the moment ... right now they are in ugly 70L test prototype boxes until I can get an amp with sufficient power for me to see that my design is going to work ie. no vent noise at xmax as the box I have in mind is very elaborate and I pretty much need to be able to design it then build it without too much adjusting. Hence the test boxes to work out the volume, vent length and size and tuning, and get that right first.

[Kittle]

oh okay - so youve done my suggestion already.

in that case - check these out:
500w amp
1kwatt amp

not sure how $US translates to $AU though.

[hunter audio]

hi

this driver may have been assembled in usa but most of the parts seems to have been sourced (if not the entire driver itself) from taiwan , that too a taiwanese co which has all its factories in mainland china

in that sence shiva s are yet better they are eminence assembled

(soft parts cone , spiders ets are form - Nuway / LCC or kurt Mueller - I guess of the Shivas , Tumult )

your parts also resemble to be used in car audio application - therefore the need of all that power

i am sure the suspension is very stiff - and hardly linear

linearity test :-

the force required to you push the cone inwards
=
to the foce required to push the cone upwards

these are again signs of chinese - parts and speakers

as for your amp problem if its a stiff driver - then u hardly need to worry about the damping factor and the slew rate / also the phase responce - just go for the highest power amp to suit your budget - may it be an IC based amp / raw power pa amps ets

sorry if i went a bit hard on the driver - I am assuming if the suspension to be stiff

suranjan das gupta

transducer design engineer

[HiFiNutNut]

One option is to build Randy Slone's Totem-Pole amp that can go up to 800w.

I finished assembling Randy Slone's Optimos amp (same circuit as the Totem-Pole but less power I suppose) last weekend and I have been spending all evening this week to listen to it. Mine is less than 150w. The sound quality of the amplifier exceeded my expectations. IMO to get that sound from a commercial amp you would be looking at paying between $3000 - $6000. It is not perfect but it can easily beat all the NAD / Rotel amps I have listened to. One of the best sounding amps I had was a Musical Fidelity 60w pure class A amp. I think the MF is slightly sweeter, but the Optimos amp seems to have the speed and power and can drive difficult speakers with ease. I did the soldering and it made music straight away - no turn on/off thumps, no hums, nothing, just silence and music. Your drivers may not need an amp as accurate as that one but if one day you want to change your speaker you know that you have a good amp to use. I initially contacted Mr. Slone but he refered me to his distributor in OZ www.ledeaudio.com. For an Optimos amp I think you can build one for under AUD$800 without the chasis. You can buy whole kits (without chasis) and it saves you time shopping for components. It is very easy to build. My only difficulty is to make the chasis - the PCBs and the heatsinks are quite large and they won't fit into a 3U rack. I will need to cut aluminim sheets and angles to make the chasis.

[Spearmint]

Hi Paul

Depending on how much you want to spend I know where there is a Crown K1 in mint condition FS in Melbourne, trouble is probably wants around $1500.00 not sure on the price, as when I was talking to him the other night he told me he still had it. He upgraded to a Quest 2400w unit.

Let me know if you are interested.

Dick

[LuxmanZ504]

You could buy my sub-amp for a reasonable price...

I picked my nickname after this amp.

It´s a Luxman Z504 stereo power amp Lab. series build in 1984.
It leaves me 2x1500 W in 8 ohm in class AB and some 3160 W mono.

You can also use it in class A mode stereo or mono.

No shipping! =)


_______________________________________________

The first cut is never the deepest...

[jleaman]

Those plate amps look a little small and iffy. 500 watts is not just 500 watts. i don't see any heat sink at all to dissipate any power from the outputs..I could be wrong but if it looks to small to complete the job it might be.. You want some raw horse power something that will grab this drivers voice coils and move them when they are to be moved not to burn them out with distortion and stuff.


What about building a pair of amps from www.aussieamplifiers.com.. i build the n-channel and it worked pretty dam good. Except i blew it up removing it from the heat sink and putting over to a new one. so i have to order 6 more fets and then it will be a live again..



I like your webpage a lot good work and i like your idea of your subwoofer enclosure's a lot too.. Great idea.. Got any drawing's?