How to Choose the Right Amplifier for Your KLH Speakers
Amplifiers do a [theoretically] simple job. They take power from your wall and put it into a speaker. But, like any good hobby, amplifier options today are abundant. So, whether you're considering your first new amp or wondering if a vintage receiver on Facebook Marketplace will work for your speakers, this blog breaks down what to look for. And perhaps more importantly, what you don't need to stress about.
Before we dive into the basics of amplification, if you simply want to know your KLH Model needs for amplification, skip ahead to the “What Each KLH Audio Speaker Needs” section towards the end of the blog post.
There are a few different types of amplifiers, but to keep things simple, let’s focus on two: integrated amplifiers and AV receivers (AVRs). Integrated amplifiers are common and combine preamp and power amp functions. That means you can adjust the volume, switch between sources like record players and CD players and power your speakers all from one box. Modern integrated amplifiers typically come with built-in streaming, digital-to-analog converters (DAC) and phono stages (for record players).
An AV Receiver (AVR) adds HDMI switching, surround processing and sometimes radio. We recommend choosing an integrated amp for music-focused systems and an AVR if you have ambitions to build a multichannel home theater.
If you’re new to listening, a streaming integrated amp is probably the best place to start. Having one box do everything you need is inherently appealing.
Understanding How Much Power You Need
On every speaker’s spec sheet, you’ll see numbers associated with “Sensitivity” and “Impedance”. Sensitivity (rated in dB, like the one above) tells you how loud a speaker plays for a given amount of power. Higher sensitivity means it needs less power to get loud; lower sensitivity means it needs more. Across the KLH lineup, sensitivity runs from 88dB (Model Three and Four) up to 91dB (Model Seven), and recommended power follows the same pattern: 30-150 watts on the low end, up to 20-250 watts for Model Seven (exact numbers below).
Impedance is the other half and tells you how difficult a speaker is to amplify. Lower impedance (4 ohms or lower) draws more current. As an example, Model Seven is rated at 4 ohms and needs an amp that can produce plenty of power at 4 ohms. Model Three, Four and Five are all easier to drive and are rated at 6 ohms. The easiest-to-drive speakers are typically 8 ohms.
Practically speaking, you need to ensure that an amplifier has at least 30 – 150 watts at 6 ohms for most of our speakers, and at least 20-250 watts at 4 ohms for Model Seven.
Think About What Inputs You Need
Match the input to what you want to play. Want to listen to records? You need a phono input, or a turntable with one built in. CDs or a tape deck? Any line-level input, like AUX, works fine. Streaming from your phone or laptop? Look for Bluetooth or Wi-Fi. Hooking up to a TV? You'll need HDMI or optical. If your amp doesn't have a phono input, an external phono preamp solves that without needing a new turntable.
What Each KLH Audio Speaker Needs
What Model Seven Needs: Because of its scale and size, Model Seven is the most demanding speaker in the lineup to amplify. It calls for a 4-ohm load that requires an amp rated to handle it. Feed it 20-250 watts of real current and it will sing. Jeremy Parker has his Model Sevens paired with a classic Harman Kardon Citation 16 power amplifier. Model Seven loves dedicated power amps like this.
What Model Five Needs: At 90.5dB sensitivity and 6-ohm load, Model Five comes alive with 20-200 watts of clean power. It's more forgiving than Model Seven, but will still be happiest when it has really substantial power feeding into it. Brian Emeka has his Model Fives paired with a HiFi Rose RS520, capable of producing 200+ watts per channel.
What Model Four Needs: Model Four shares Model Five's easy-to-drive 6-ohm load, so 30-150 watts is all it takes to fill the right room. It's built for placement flexibility, and while it will be happiest with at least 150 watts to play around with, it still sounds fantastic with 50-100 watts.
What Model Three Needs: Also 6 ohms and 88dB sensitive, Model Three asks for the same 30-150 watts as Model Four and rewards it with surprisingly big, full-range sound from a bookshelf footprint. It doesn't need much power to sound like it's punching above its size. Robert Rademaker has his Model Threes paired with a Denon PMA-1500NE, which produces plenty of power to animate them.
What You Should Plan to Spend
Don’t skimp on amp quality. The more power the better, KLH Audio speakers really come alive when you give them more juice. On the upside, amplifiers can last a long time if they’re well-maintained. Retro units from the '70s and '80s still perform beautifully today.
