Is this amp good enough for a shiva (1 Viewer)

[Anthony*gw]

Greetings, I am just about finished building my 140L sub,with it i will be using a Dynaco 400 stereo amp,it was my uncle's,i guess he doesn't want it anymore so he handed it down to me (lucky me),and i will be using the shiva driver that i ordered already but unfortunately it is not available right now,but i am willing to wait because Bob Reimer from creativesound said that they expect to have more by end of month.Since it's a stereo amp how should i wire shiva to get 4ohm load?


here are some specs for my amp:Specifications:

Power Output:

20 Hz to 20 KHz, both channels driven:

200 watts continuous average per channel @ 8 ohms;
300 watts continuous average per channel @ 4 ohms;
100 watts continuous average per channel @ 16 ohms.
Monophonically:
600 watts rms @ 8 ohms.

Intermodulation Distortion: Less than 0.1% at any power level up to 200 watts rms per channel into 8 ohms with any combination of test frequencies. Distortion reduces at lower power levels. Typically less than 0.03%.

Harmonic Distortion: Less than 0.25% at any power level up to 200 watts rms per channel into 8 ohms at any frequency between 20 Hz and 20 KHz with both channels driven. Distortion reduces at lower power levels. Typically less than 0.05%.

Power at Clipping, single channel, 2500 Hz, less than 1% distortion:

235 watts @ 8 ohms;
350 watts @ 4 ohms;
135 watts @ 16 ohms.
Ppower bandwidth: 5 Hz to 35 KHz at less than 0.25% total harmonic distortion - half power output, 8 ohm load.

Frequency Response: +0, -1 dB, 8 Hz - 50 KHz @ 1 watt into 8 ohms; ±0.5 dB, 20 Hz - 20 KHz @ 200 watts.

Hum and Noise: Better than 100 dB below rated output, full spectrum.

Input: 50,000 ohm load; 1.6 volts for 200 watts @ 8 ohms.

Slewing Rate: 8 volts per microsecond.

Damping Factor:

Greater than 80 to 1 KHz into 8 ohms;
Greater than 30 to 10 KHz into 8 ohms.
Channel Separation: Greater than 60 dB by IHF standards. sorry for the long post.

 

[Anthony*gw]

Power at Clipping, single channel, 2500 Hz, less than 1% distortion: 235 watts @ 8 ohms; 350 watts @ 4 ohms; 135 watts @ 16 ohms.

what does that mean,i heard alot about amp clipping on these boards and from what i gather clipping is when the amp does not have enough power to feed the driver so i feeds it wrong signals causing the speaker to sound funny right?
if i wire the voice coils separate would that be automatically 4ohms or will i just be giving 200w to each voice coil

 

[GrahamT]

I suggest you use the left channel for one coil and the Right for the other. THis way the amp is seeing an 8 ohm load. I am not sure what the specs mean either. This will be plenty of power for the shiva. BTW I bought my amp and Tempest from Bob.

 

[Ryan Schnacke]

Clipping is when you ask for more signal amplitude than the power supply can support. Music is made up of sinusoidal signals. Think about what a sine wave looks like. Now imagine if your power supply gave up before the signal reached the peak of the sine wave. The signal would go flat once the supply reached its limit. Then as the input signal curves back down again the output will start to follow it again. This waveform would be a sinusoid with the peaks "clipped" off.

This is tough on the amp because you're asking it to perform beyond its abilities. Its tough on the driver because during the flattened peaks you're putting a DC voltage on the coils. Its especially tough on tweeters because the transition from the normal sine wave to the flat signal is abrupt. Abrupt transitions like this are really composed of many high frequency signals, in this case at very high power levels. Clipping is probably the most common cause of blown tweeters.

 

[Anthony*gw]

Hey thanks for the input guys.so is there no way i can get 4ohms from the stereo amp and still use both channels,or will the 8ohm load to both coils be enough power?

 

[GrahamT]

I think that 400 watts into 8 ohms will be more than enough fo the shiva. If you really want more maybe that amp can be bridged but I am not sure.

 

[Ryan Schnacke]

You've got two voice coils at 8 ohms each. If you hook one coil to each amp channel then you'll have up to 400 watts available - more than enough to bottom that woofer out in most of the recommended alignments.

You could wire the the to coils in parallel and connect to one amp channel. You'd have 300 watts which is just about right. But I'd probably just run one coil to each channel since the 8 ohm load is easier on the amp.

 

[DanWiggins]

In that box, 200W is plenty. I'd just wire the two voice coils in parallel and hang them off of one channel - 300W is more than enough for that large box.

Dan Wiggins
Adire Audio

 

[Anthony*gw]

In that box, 200W is plenty. I'd just wire the two voice coils in parallel and hang them off of one channel - 300W is more than enough for that large box.

I thought 400w sound like alot of power because mostly everyone uses 250w amps.thanks Dan i will wire them in parallel and just use one channel.

 

[Anthony*gw]

I think that 400 watts into 8 ohms will be more than enough fo the shiva. If you really want more maybe that amp can be bridged but I am not sure.

yes GrahamT the amp can be bridged but that will give you a total of 600w,but i think that might be a little too much.

When everything is complete i will post some pics of my sub.