HELP! Amplifier Question


New member
Username: Jrhobson2

Post Number: 1
Registered: Nov-08
Hi, I just came into a pair of Visonik V6T passive 3-way Studio Monitor Speakers and I don't really know anything about amplifiers so I don't know how to hook them up to my system.

Each Speaker has a Built-in 6 Inch Woofer, 3.5 Inch Midrange, and a 2.5 Inch Piezo Full Range Horn Tweeter
Model: V6T
200 Watts Power Handling
100 Watts RMS Power Handling
Frequency Response:
Subwoofer: 60 Hz -- 300 Hz
Midrange: 300 Hz -- 800 Hz
Tweeter: 800 Hz -- 22 kHz
Dimensions: 14" Width x 6.5" Bottom Depth x 4.5" Top Depth x 9" Height Each
Impedance: 4 Ohm

I do sound design for media and I have the Phonic *Helix 18 FireWire MKII Mixer hooked up to my computer via firewire which sends two channels out to the mixer. The Outs on the mixer are 1/4 and XLR.

What amplifier would I need to hook up the two Visonik speakers to right and left outs on the Helix 18 mixer?
Thanks for your help.

Platinum Member
Username: Nuck

Post Number: 11086
Registered: Dec-04
Alex, I suggest you talk to a pro audio dealer. they can determine an amplifier for you that matches the output impedence of the mixer, and will accept mic connection(1/4) or balanced connection, the XLR. This will also be far less expensive than a home amp, which tends to be expensive for those connections.

Also, the specs on your speakers are not so promising. The lowest bass response being 60Hz means that a lot of the bass information will not be reproduced. If you like these speakers, you might consider a subwoofer as well.

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 13085
Registered: May-04

There wouldn't appear to be anything special about the connection to your speakers or mixer. Possibly you'll need an adapter to go from 1/4" out on the mixer to RCA in on an amplifier and that should make virtually any amplifier work with your mixer. The speakers have a nominal four Ohm rating so you'll need something more than a basic receiver. Try a catalog such as Audio Advisor or Parts Express if you're after a consumer audio amplifier, go to a pro audio shop or a catalog would be Guitar Center or Musician's Friend if you want to buy something suited to industrial applications. Tell them the specs on your speakers and the general information regarding your mixer. Other than that, there are too many possibilities that will work to have us suggest a specific brand or model. Determine your budget and go from there.

To address the subwoofer issue, 60Hz is 1/2 octave shy of the lowest note typically found in rock music which is the 41Hz low E on a bass. There's no way to tell how honest Visonic is about their specs but placing the speakers against a wall will gain an additional few Hz extension in the bottom octave. I have no idea what you listen to or how loud or whether you have placement restrictions with your speakers/room. A sub would probably be a good idea if you find the speakers lacking in bass but you might want to look for better speakers before you buy a sub.


New member
Username: Jrhobson2

Post Number: 2
Registered: Nov-08
Thanks for the advice. but I'm still a little confused about the amplifier. Since the speakers are 100 watt RMS at 4 ohms I should be looking at amplifiers that also have a 100 watts into 4 ohms right?

Silver Member
Username: Jrbay

Livonia [Detroit area], Michigan USA

Post Number: 489
Registered: Feb-08
As Jan mentioned above keep those specs in mind while shopping. The 4 ohms is more critical than the 100 watts and narrows down what will actually work in your case. Most home receivers/amplifiers run at 8 or 6 ohms and would therefore not be suitable.

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 13089
Registered: May-04

No. The amp should be capable of driving a four Ohm load and the power increase into the lower impedance load of four Ohms should be on the order of 50-70% higher than its eight Ohm rating. Don't concern yourself with the amount of watage you buy, the difference between 100 and 200 watts RMS is insignificant and the smaller amp may actually sound louder if it is a better amplifier. Buy what you can afford that sounds the best.


Gold Member
Username: Frank_abela

Berkshire UK

Post Number: 3335
Registered: Sep-04

The power rating on the back of the speaker tells you the maximum amount of power the speaker can accept at a burst. In your case it can handle a very short burst of 200w. They say 100w RMS, probably because that's a reasonable safe guesstimate in amplifier terms. 100w RMS is actually about 141w peak and since there's very little difference between 141w and 200w in amplifier terms they're probably just playing safe.

In an average sized room (anything under 14ft x 12ft), when you play music at just room filling volume, you're usually just putting 4 - 5 watts of power through the speakers. If you're playing classical and there's a crescendo, that figure might rise to 10 - 15 watts. This is dynamic power dependant on the signal.

As you turn up the volume you will get more sound until either the amplifier starts to distort or the speakers hit their end stops. In the former case, the amplifier may break the speakers or go up in smoke. In the latter case, the speakers will give a 'pop' when they hit their end stops. There is no damage provided you stop what you're doing. perisitent popping will eventually break the speakers.

Amplifier power is also an interesting subject. Amplifiers talk of developing 100W, say, but the fact is that the amount of power developed by an amplifier is only fixed into a fixed load. Speakers present a variable load depending on the frequency of the signal. So when a speaker says it's a 4 ohm load, this is a nominal value given to the speaker by the manufacturer meaning 'around 4 ohms, kind of, on a good day with a following wind'. What they really mean is that "it'll dip below 4 ohms at some point but not long enough to trouble most amplifiers this unit will be sold with". Incidentally, the lower the impedance the more difficult the load. Yours are 4 ohms so they're a bit more difficult to drive than some others. Many speakers are 4 ohms nowadays and many amplifiers have been designed to cope with this. Look for amplifiers that are described as having a stiff or a big power supply that have power outputs upwards of 40w and you're in business. Models to consider would include (in no particular order) NAD's C325BEE, Rega's Brio, Cambridge Audio Azur 640A. it goes up in price from there...

« Previous Thread Next Thread »

Main Forums

Today's Posts

Forum Help

Follow Us