Zaph Audio ZA5.2 DIY Kit Speaker Review

[stevenswall]

Just for fun, go here and use the Amplifier Power Required calculator using 3 meters listening distance, 90dB, 82dB @ 1w/1m and 6dB headroom (which is on the low side for some of my music) and you get 226 watts. With a speaker spec'd at 85 1w/1m you only need 113w. For 88dB 1w/1m it's 57 watts.

226 watts. Not bad, I figured it would be a lot higher. Looks like there are several amps that would provide that much power for about as much as the speakers themselves.

 

[tuga]

On average, I like to listen in the upper 80's to low 90's output level. And my MLP is also 8-12 feet away from the speakers. With a low 80's sensitivity rating I'll have to dump a lot of power in to the speaker to have enough output for high dynamic range music and in doing so, increase the *likelihood* of running in to distortion and/or compression issues. No bueno.

Just for fun, go here and use the Amplifier Power Required calculator using 3 meters listening distance, 90dB, 82dB @ 1w/1m and 6dB headroom (which is on the low side for some of my music) and you get 226 watts. With a speaker spec'd at 85 1w/1m you only need 113w. For 88dB 1w/1m it's 57 watts.

What my needs are and what others' needs are would be different. So, that's why I said the low sensitivity makes this speaker a hard pass for me. I won't buy a speaker or drive-unit that's below 85dB sensitivity.

Shouldn't the speaker's nominal impedance go into the calculations?

 

[hardisj]

Shouldn't the speaker's nominal impedance go into the calculations?

That’s what the sensitivity is for.

 

[Haint]

226 watts. Not bad, I figured it would be a lot higher. Looks like there are several amps that would provide that much power for about as much as the speakers themselves.

That calculator's probably assuming the full -6dB drop per distance doubling, yes? -3 or -4dB for a typically reflective domestic space is the rule of thumb I've always seen passed around. Assuming that's true you could likely subtract ~4dB to arrive at a more real world 3 meter watt/spl figure. That would put 90dB at around 90W.

 

[Biblob]

@amirm , may I be so rude to ask if you would test the Kali LP-6 next?

 

[mhardy6647]

That’s what the sensitivity is for.

Indeed -- as long as sensitivity is either referenced to power in watts or to signal volts (2.83 V = 1 watt into 8 ohms) and the nominal impedance of the load is known.
[grouchy guy aside follows!]

I sometimes wonder if the proliferation of nominally 4 ohm loudspeakers in the past 25 years or so has been largely a diversionary tactic to seemingly 'add' 3 dB to the sensitivity number (when expressed as dB per 2.83 V @ x meters) in a way that's not incorrect but not altogether transparent to the great unwashed. On the the other hand, the great unwashed that I invoke probably doesn't know what the sensitivity specification means anyway.


Sorry, but a priori, I'm not a big fan of low impedance (or low sensitivity, for that matter) loudspeakers -- especially units with particularly gnarly impedance & phase curves. Just because a loudspeaker designer can make his or her baby a torture test for an amplifier doesn't mean s/he should .

We're at nominally 16 ohm & about 102 dB/watt @ 1 meter here
I like the loudspeaker to do the work.

 

[amirm]

@amirm , may I be so rude to ask if you would test the Kali LP-6 next?

I will see.

 

[MZKM]

What makes high or low sensitivity bad? Isn't the cost per watt for amps right now cheaper than at any point in history?

If a speaker has low sensitivity and low power handling, that’s bad. This Zaph mid-woofer has a rated power handling of just 60W.

 

[MZKM]

That calculator's probably assuming the full -6dB drop per distance doubling, yes? -3 or -4dB for a typically reflective domestic space is the rule of thumb I've always seen passed around. Assuming that's true you could likely subtract ~4dB to arrive at a more real world 3 meter watt/spl figure. That would put 90dB at around 90W.

Yep, they state that caveat. I’ve found 3dB-4dB to be realistic. I’ve measured a ~8dB loss in sensitivity going from 1m to my 12ft listening distance.

 

[phoenixdogfan]

For $342 a pair, this seems like a steal.

 

[Sancus]

For $342 a pair, this seems like a steal.

A bunch of parts is not a speaker, though, unless you consider your time to have $0 value.

 

[Francis Vaughan]

For $342 a pair, this seems like a steal.

Compared to the JBL 305P MKII maybe not so much. Apples to oranges in some respects but not an unreasonable question about where to put one’s money.

 

[richard12511]

Compared to the JBL 305P MKII maybe not so much. Apples to oranges in some respects but not an unreasonable question about where to put one’s money.

I would say they're pretty comparable to the JBLs value wise. They seem to measure quite a bit better than the JBLs, but they're a little bit more expensive and you have to build them yourself. If they meet your spl needs, then you have to ask "is the increase in sound quality over the JBLs worth an extra $50 and time/hassle to build?" I imagine folks would be pretty split on that.

 

[Rick Sykora]

As I pointed out earlier, am not the designer, but I thought a little context might help here...

The ZA5.2 is a bookshelf speaker with a 5 inch woofer that can be built for under $400/pair. The designer does not make any claims that it will outperform anything else, but he is an accomplished speaker engineer. While the ZA5.2 does not have much useful output below 80 Hz, it can get bass reinforcement via the room. This would be true of any comparable speaker with a 5" woofer. Most of these woofers have sensitivities around 85 dB +/- 3 dB. To do much better, you either need a bigger driver or an active design.

ZA5.2s (or any traditional small speakers) are not going to fill a huge space with sound
(even if they had much larger power handling and bigger amplification), but they are surprisingly good in my 15 x 21 living room (with subwoofer) or a smaller room on their own.

Thanks to @MZKM for adding ZA5.2s to the speaker database and we will see how they stand the test of time as more speakers are tested. Amir has a Dayton C-note queued to test and so will get a budget DIY speaker to compare soon! Was going to make the usual plea for more funding, but given other current challenges, just stay safe and healthy for now.

 

[Vuki]

A bunch of parts is not a speaker, though, unless you consider your time to have $0 value.

Of course many audio hobbists don't consider time spent enjoying a hobby as expense. People pay money to play golf, tennis or go fishing - so time spent building loudspeakers is pure profit

 

[Francis Vaughan]

Absolutely not. I have burnt some horrendous amount of my life with soldering iron or saw in hand. Journey is the reward and all that. Got some nice toys out of it as well.

 

[mhardy6647]

A bunch of parts is not a speaker, though, unless you consider your time to have $0 value.

That'd be me

 

[Dave-Oh]

… Am a bit surprised by the low sensitivity as do not use very high power amps and have not had any obvious issues driving them to high levels.

Nor did I when I built a pair and had them in my system for a while. The bass also didn't sound quite as deficient as described by Amir but I had a stereo pair, not in a controlled or consistent listening space.

 

[ta240]

A bunch of parts is not a speaker, though, unless you consider your time to have $0 value.

The golden rule with audio DIY is if you don't enjoy the process it isn't worth it.

I'm with Vuki, the build is the fun for me. I'd be building non-stop if I had something to do with the finished product but I'm running out of room to store them.

 

[Juhazi]

Actually I am a loudspeaker DIY person too. First kit around 1974... I have gradually bought tools that I need for house and summer cabin work too.

But still I think 2-ways are not worth doing, except as for learning. 3-4 ways and BIG subs is what I design and build now.