Amp and eq for Precision devices PD2150... Hypex?

[JiiMKV]

Hello.


I have a pd2150 driver (Precision Devices International Limited) and im wondering what would be the best option for amplification? I am thinking of building something with Hypex ucd modules. the driver is going to be in a closed enclosure so a lot of equalization is needed to go below 20hz -> I need a lot of power.

Driver is rated 1000W rms 8 Ohms. would it be smart to use 2 ucd-400HG modules bridged? That would give me 800w to 8 ohms. The thing that troubles me is that I have heard that the drivers impedance changes with the frequency and that a bridged amp loses power output when the impedence drops. Would this be a broblem? what would you recommend for amplification? (not a plate amp)

What would you recommend for equalization? is there any high quality eq modules that i could integrate in the same box with the amp?


Ps. Sorry for my bad english.

[nigelwright7557]

Originally Posted by JiiMKV

Hello.

The thing that troubles me is that I have heard that the drivers impedance changes with the frequency and that a bridged amp loses power output when the impedence drops. Would this be a broblem?

Generally all speakers go higher impedance as the frequency goes up.
Its partly because they are inductors.
This is why a zobel network is added to the output of the amplifier to try and keep the load constant on the amplifer over the full frequency spectrum.

The UCD400 modules should be fine, they do seem to be popular.

[tinitus]

Originally Posted by JiiMKV

would it be smart to use 2 ucd-400HG modules bridged? That would give me 800w to 8 ohms.

note that Hypex power specs are into 4ohm
which means the 400watt will be 200watt into 8ohm

now, your driver may be 8ohm nominal, but is 5.5ohm Re(dc)
and being a sub, and with lots of Eg, 5ohm is where you are heading

if you want to bridge such power amp modules, you may have to lower supply voltage a bit


I know its not classD
but I would consider this amp module from
Ground Sound

mind you, high power, not a trivial task, experience requested

[JiiMKV]

Thank you for your answers. The reason i was thinking of brdging the two ucd400 amps was this questioon i foud by following links in the hypex netpage:

Q: I need double the power in an 8Ohm load than a UcD amplifier can produce. Is there some way I can bridge two, for example, UcD400’s?
A: You need to drive one of the modules 180 degrees out of phase by simply swapping the negative and positive input signal wires. Tie the loudspeaker between both positive loudspeaker outputs of the amplifiers and connect a 47n/200V capacitor across the loudspeaker terminals at the amplifiers’ side. This set-up is most applicable for 8 Ohm loads since each amplifier ‘sees’ 4 Ohms with an 8 Ohm load attached. A 4 Ohm load might trigger the current protection leaving you with not nearly as much power as you might have expected.


Ok. Now i noticed that the drivers nominal 8 Ohms is not the correct value to look at. Thanks Tinitus
Maybe one ucd700 would be just fine? what is the difference between the ucd modules and the modules used in hypex plate amps?

How about the ICE amps? they have a 1000w 4 Ohm module. Some say that Ice amps are rubbish (unable to deliver the promised power) and hard to get by normal person but i have heard that adam audio uses the 1000w ice amp in their Adam sub 2100 studio subwoofer. looks like the same diver too.

[StigErik]

ICE amps are hard to get for DIY purposes, so I would stick with Hypex, which sounds better also at least at mid and higher frequencies. That being said, the big ICE 1000ASP is a very good subwoofer amp, and it can deliver full continous power if sufficient cooling is provided. Max output is approx 1250 W into 4 ohms.

The ICEpower ASC and ASX2 series can not deliver continous full power, as they are designed for delivering music signals only, where the average power is 1/8 of the peak power. I would not choose any of those models for a subwoofer, but the ICEpower ASP modules are more than ok.