Zaph Audio ZA5.2 DIY Kit Speaker Review

[MZKM]

Thanks, that makes sense. I should have read the review more closely

I just checks my spreadsheet calculations, the cardinality of my bands are the same, so it looks like it didn't mess anything up.

 

[cheatingboy]

This is fair question. For me, I can tell you that the ZA5.2 speaker I built is very comparable to the posted design. Both my frequency response and the impedance graphs are comparable to ones on the Zaph site. That said, if you do not measure to verify results, you risk not matching the design (miswiring, bad solder joints, a bad component, etc.). Note that many of the components involved have wide tolerances too. Depending on manufacturer, woofers particularly can vary significantly from batch to batch.

Otoh, I (and others) can improve on the design too. Even my crudest cabinetry is better than what you get with commercial stuff. Also, the quality of the drivers and crossover components is far better too. But I am also the tester, quality control, and warranty repair when I DIY. So, in the end, I control more of the outcome.

Speaker designs are tradeoffs. This one may be low sensitivity, but is pretty good in many other ways. Looking through what Amir has tested to date, there is not any speaker value that clearly stands out in this price range. For that matter, there are a number that are far worse.

I am interested in this product. Can you tell me about the kit purchase options?

[Accessories]
Ported Version Optional Accessories Package
Sealed Version Optional Accessories Package

[Crossover Version]
Original Crossover Design
In-Wall Version of Crossover
Reduced BSC Version of Crossover (for near wall, on-wall, in-shelf applications)
Crossovers Only - No Drivers

[Tweeter Cap]
Bennic XPP
ClarityCap PX
ClarityCap ESA
Mundorf EVO Oil

[Binding Posts\/Input Cups Incl. 10% Discount]
G-POSTL
HG-POST
Propeller Posts 35mm
NB-CUP
DB-CUP
R-CUP

 

[Rick Sykora]

I am interested in this product. Can you tell me about the kit purchase options?

[Accessories]
Ported Version Optional Accessories Package
Sealed Version Optional Accessories Package

[Crossover Version]
Original Crossover Design
In-Wall Version of Crossover
Reduced BSC Version of Crossover (for near wall, on-wall, in-shelf applications)
Crossovers Only - No Drivers

[Tweeter Cap]
Bennic XPP
ClarityCap PX
ClarityCap ESA
Mundorf EVO Oil

[Binding Posts\/Input Cups Incl. 10% Discount]
G-POSTL
HG-POST
Propeller Posts 35mm
NB-CUP
DB-CUP
R-CUP

I can help a bit, but should not be in this review thread.

Will start a discussion with you directly.

 

[ta240]

I know that Amir put "conflict of interest" disclaimer in every harman product review, but nevertheless bashing this measurement-wise quite OK looking speaker doesn't seem appropriate in light of the revel f35 review:
Amir's conclusion:
"While in the "budget" portion of Revel line, and too low priced to be considered as "high-end" by the audio industry, the Revel F35 objectively and subjectively produces stellar performance. A bit of low frequency EQ is all it took for it to sound good without any fiddling with location, toe-in, room treatment, etc, etc. "

Maybe with a bit of EQ Zaph could also produce stellar performance?

It does make for odd comparisons between tested speakers if some are EQ'd and others aren't. And I'd swear I'd read before on here that if you need an equalizer for your speakers then what you really need are better speakers.

That is the key. To listen at moderate volume.

I have a pair of these in my garage. At low to medium levels I find them quite nice. I just use it as background music while I work on things and never go loud enough that they could even be heard from the street because I have an aversion to being 'that guy' that thinks the world wants to listen to my music. In this use the lack of bass is probably a benefit because it keeps the sound from traveling as far and the high frequencies give it an airy sound that fills the garage. But I will admit that I am probably far from the normal user when it comes to audio and the volume levels I use.

 

[HammerSandwich]

Maybe with a bit of EQ Zaph could also produce stellar performance?

Don't ignore the directivity, which cannot be EQed.

Both speakers have reasonably similar DIs through the mids, but waveguide versus dome causes very different behavior in the top 3 octaves.

 

[DDF]

If I remember the study correctly, resonances this low in amplitude are only audible if they also have very low Q (e.g. Q=0.1). That makes them more than a "blip" on the response curve. The extreme case is a spectral tilt, which we can easily detect even if the slope is very small, but it's also quite visible on a frequency response graph too.

Also note that the study was only about detection thresholds, not preference. The impact of low-Q, low-amplitude (i.e. "broad trends" in frequency response) on preference is controversial.

I feel your response was disappointingly argumentative, without any back up. Addressing your criticisms one at a time:
1. Audibility of -28 dB resonance was with Q a factor of ten higher than you remembered (Q=1), just detectable at 2kHz with white noise. It certainly sets a challenging design target but I play it safe and remove these if possible.
2. Good luck seeing a 0.34 dB Q=1 peak on the summed frequency response (yes, a blip if you do the math) and knowing it was caused by an individual driver resonance, such as woofer cone break up, without measuring the driver independently.
3. If one prefers colouration, sure, ignore resonances. I know you feel Toole is a trust worthy source, so feel free look up his advice how resonances map into preference.

 

[Prana Ferox]

Philosophically, I think it is not wise to diy this kind of simple speaker. Labor time, tools and materials cost/benefit is huge

I would disagree (seeing as I have several pairs of DIY speakers within eyesight). As in all things it's a factor of what you're going for.

First of all, these small kits are easy projects both to learn DIY techniques and learn more about speakers in general - how ports work, why enclosures are built / sized / braced like they are, how crossovers function etc etc. They also encourage critical listening. You see people building kits with friends / loved ones and spreading enthusiasm for the hobby. The learning and social experience should not be discounted.

Also, frankly, the time / resource cost is minimal. This kit is slightly higher in effort because WW cut the wood himself. In the US at least, you can usually have a big box store (Lowes, Home Depot etc) rough cut the wood for you at time of sale, if you don't have the ability. Alternately, Parts Express and DIYSoundGroup, among others, sell precision pre-cut flat packs for many kits. With a precut pack you can assemble these on a kitchen table.

A kit like the C-Notes or Overnight Sensations can be had for around $100 a pair, adding a couple bucks for binding posts, minus a couple bucks for coupons and sales. They can be assembled with masking tape and wood glue (another few bucks) in spare time at whatever pace. You need a soldering iron and solder to make the crossovers. You need a drill for the binding posts. Some kits need screws and interconnecting wire, some come with those. That's it.

(Emphasis on the crossovers and that these kits have real ones. If you look at retail speakers at this end of the market, if you're lucky you're getting an inductor on the woofer and a cap + padding resistor on the tweeter. It's no wonder they have poor driver integration and other artifacts.)

The expense and effort comes in finishing the enclosures, and that's up to the builder. With the Baltic Birch kits in particular you can get a good look with very minimal work. If you want to take an MDF box and get a piano-gloss paint finish, or if you want exotic real wood veneer, it will cost, but so would buying speakers like this retail.

So you can get a KTB, an Allo Volt+ amp, and a DIY kit and have a very decent sounding computer room / bedroom sound system (assuming you have a source) for ~300$ US. That is, in this hobby, peanuts, and ensures a low cost of entry for budding audiophiles and enthusiasts. From there people can move up to refrigerator-sized speakers or active monitors the cost of a used car, if they so desire - or not.

 

[QMuse]

3. If one prefers colouration, sure, ignore resonances. I know you feel Toole is a trust worthy source, so feel free look up his advice how resonances map into preference.

Wouldn't "colouration" show as increased THD in distortion measurement?

 

[amirm]

I know that Amir put "conflict of interest" disclaimer in every harman product review, but nevertheless bashing this measurement-wise quite OK looking speaker doesn't seem appropriate in light of the revel f35 review:

What would you like me to do? Listen to a speaker, find it unsatisfactory, and report it otherwise?

The implication that I heard it sound better but lied is quite a reach. And unappreciated.

 

[stevenswall]

Hard pass based on the sensitivity alone. Though, if I were listening somewhat nearfield and/or had a baby in the next room then the FR looks decent enough. The THD is pretty abysmal, though, but again, low sensitivity and 5" midwoofer doesn't exactly exude "crank it to max, baby!". I'm assuming baffle step compensation is what knocked this guy down in to the low mid-80's?

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

 

[Vuki]

What would you like me to do? Listen to a speaker, find it unsatisfactory, and report it otherwise?

The implication that I heard it sound better but lied is quite a reach. And unappreciated.

I think you didn't give them equal chance. F35 was dissapointing but with some eq got "stellar performance". Maybe zaph would be stellar performer too if you gave it a chance (measurements certainly don't deny it)?

Please don't misunderstand me- I love ASR and everything you do for our hobby and greatly appreciate it!

 

[HammerSandwich]

Lower sensitivity/efficiency implies some combination of lower maximum SPL, higher distortion & greater dynamic compression (i.e., FR differences as SPL changes). Probably some losses in all three areas. Plus the costs of bigger amps, as you noted.

 

[amirm]

I think you didn't give them equal chance. F35 was dissapointing but with some eq got "stellar performance". Maybe zaph would be stellar performer too if you gave it a chance (measurements certainly don't deny it)?

The EQ is for room compensation, not speaker. It is a single band at a room mode that was constant with three speakers I measured. I applied the same to Zaph. It made a tiny improvement because it has so little bass.

Let me repeat: I am absolutely NOT equalizing speakers. Nor was I heavy handed with Room EQ. Corner placement is causing room modes to accentuate some so I am compensating for that.

Removing the room mode makes the speaker judgement more universal in the same manner free-field (anechoic) measurements do.

 

[hardisj]

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

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.

 

[QMuse]

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.

Distortion is proportional with driver membrane excursion, not with how many watts are needed to achieve that excursion.

 

[hardisj]

Distortion is proportional with driver membrane excursion, not with how many watts are needed to achieve that excursion.

Yea... I know that... but if I'm trying to get a speaker up to a certain volume and don't put a crossover on it then you get what we see here.

Compression issues are also a problem as are resonances caused by basket interference, non-compliance with the surround/cone termination (which do vary with input voltage and thus are called "non-linear distortion").

 

[QMuse]

Yea... I know that... but if I'm trying to get a speaker up to a certain volume and don't put a crossover on it then you get what we see here.

IMO you should have digital crossvoer to perform such test instead of pushing signal to a driver without crossover.

Compression issues are also a problem as are resonances caused by basket interference, non-compliance with the surround/cone termination (which do vary with input voltage and thus are called "non-linear distortion").

Compression issue is also related to SPL and not to sensitivity. It's not that speakers with lower sensitivity can't reach same max SPL as speakers with normal sensitivity, they just need more power to do so. Unless of course we are speaking of extreme cases.

 

[Jon AA]

It's not that speakers with lower sensitivity can't reach same max SPL as speakers with normal sensitivity, they just need more power to do so. Unless of course we are speaking of extreme cases.

Actually I think "extreme" should be replaced with "most" cases. While it's possible for a speaker with low sensitivity to be capable of the same max SPL as a much higher sensitivity speaker, that's just not usually the case with real world speakers.

 

[HammerSandwich]

Distortion is proportional with driver membrane excursion, not with how many watts are needed to achieve that excursion.

We all agree that excursion is one cause of distortion. But hasn't Purifi shown that there is another distortion behavior which is related to applied current?

 

[QMuse]

We all agree that excursion is one cause of distortion. But hasn't Purifi shown that there is another distortion behavior which is related to applied current?

Sure, but I think it matters only with speakers with extremely low sensitivity and most speakers don't fall in that cathegory.