• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

JBL A180 Tower Speaker Review

Rate this speaker:

  • 1. Poor (headless panther)

    Votes: 35 16.8%
  • 2. Not terrible (postman panther)

    Votes: 121 58.2%
  • 3. Fine (happy panther

    Votes: 48 23.1%
  • 4. Great (golfing panther)

    Votes: 4 1.9%

  • Total voters
    208

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
7,604
Likes
7,313
Location
UK
I mentioned that vertical dispersion won't be as smooth as with a 2.5, but vertical dispersion isn't nearly as important as smooth horizontal dispersion, which is excellent on both the stock and my modded version. I've been doing this professionally for over 20 years and have a pretty good handle on the complexities of crossover design. In this case, I had to go with what I was given in terms of driver layout. The object of the exercise is to provide a fairly inexpensive upgrade for the 180's should they go on sale again, not to design the best of all possible crossovers for this speaker.
I maybe one of the earliest speaker designer who used 2.5-way crossover, in your words a decade before you started designing crossovers professionally. Silver 5L was designed in 1992, stayed on sale for a decade and sold all over the world. The crossover on 5L is at 1500Hz. Your crossover is at 2kHz and the design use larger cone drivers.

I am sure you know that if the same sound is generated from two sources that are more than a wavelength apart there will be loping in the directivity pattern. Loping effect is not as simple as what you describe as "won't be as smooth". The wavelength at that the crossover frequency is 17cm. Depending on how tall the listener everyone will hear a different sound!
 
Last edited:

thewas

Master Contributor
Forum Donor
Joined
Jan 15, 2020
Messages
6,731
Likes
16,157
I maybe one of the earliest (if not the earliest) speaker designer who used 2.5-way crossover, in your words a decade before you started designing crossovers professionally. Silver 5L was designed in 1992, stayed on sale for a decade and sold all over the world.
B&W DM 14 from 1980 was also 2.5 way, am quite positive there were also some earlier implemenations.
 

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
7,604
Likes
7,313
Location
UK
As others have pointed out, the listed schematic is for a different speaker--one that doesn't use a 2.5 architecture. The big inductor filters both woofers.
I am confused. If both woofers have the same inductor in series then why do they have different response curves? Red vs black?

index.php
 

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
7,604
Likes
7,313
Location
UK
B&W DM 14 from 1980 was also 2.5 way, am quite positive there were also some earlier implemenations.
Thank you for pointed that out. As you may have noticed I did say one of the earliest. However, I apologise for sounding cocky.
 

cavedriver

Addicted to Fun and Learning
Joined
Jul 10, 2020
Messages
629
Likes
602
Location
Maryland, USA
I am confused. If both woofers have the same inductor in series then why do they have different response curves? Red vs black?
Again, the crossover circuit that was published earlier in this thread is NOT for the same speaker. It is for JBL's (older?) Studio 190 (see post #95 by Nonick). Several people then made comments observing on the design of that crossover without clarifying that they were commenting on another speaker. The circuit for the crossover for the Stage 180 has not been shown in this thread, only pictures of the crossover boards. Maybe Dennis will report on what the actual stock circuit of the stage A180 is later if he shares his mod when he is done with it. In the meantime I am tempted to pull the crossover from one of my A190's and share that just to resolve this topic.
 

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
7,604
Likes
7,313
Location
UK
Again, the crossover circuit that was published earlier in this thread is NOT for the same speaker. It is for JBL's (older?) Studio 190 (see post #95 by Nonick). Several people then made comments observing on the design of that crossover without clarifying that they were commenting on another speaker. The circuit for the crossover for the Stage 180 has not been shown in this thread, only pictures of the crossover boards. Maybe Dennis will report on what the actual stock circuit of the stage A180 is later if he shares his mod when he is done with it.
As others have pointed out, the listed schematic is for a different speaker--one that doesn't use a 2.5 architecture. The big inductor filters both woofers.
I posted the individual driver FR chart copied from the review of this unit. It shows different responses for the two woofers. Why the woofers have different FR if they are connected in parallel?
 

cavedriver

Addicted to Fun and Learning
Joined
Jul 10, 2020
Messages
629
Likes
602
Location
Maryland, USA
I posted the individual driver FR chart copied from the review of this unit. It shows different responses for the two woofers. Why the woofers have different FR if they are connected in parallel?
It's not the FR chart that is for the wrong speaker, it's the assertion that the woofers are in parallel. Isn't the crossover for the Stage 180 that we are now talking about a 2.5 design, suggesting that the second woofer is not simply in parallel with the first? The woofers that we know are in parallel are on the Studio speaker circuit diagram from post 95 and not for this speaker.
 

tw 2022

Addicted to Fun and Learning
Joined
Apr 11, 2022
Messages
878
Likes
742
There is no disrespect but no human had so far managed to change the laws of physics. There is a reason why there is always a single midrange driver, hence running two drivers at 2kHz will cause issues which will be audible.
i'll take your word for it, but i'll still defer to Dennis , he builds some of the best speakers in the world for both his own company and Salk audio... i'm thinking that an a180 that he "fixed" by converting it to a 2 way still beats out an a180 that won't work as well as a 2.5 way...i'm sure your point is valid, but i'm thinking that the speaker is only viable at low cost including mod, to most folks...
 

More Dynamics Please

Addicted to Fun and Learning
Joined
Nov 18, 2020
Messages
562
Likes
752
Location
USA
Well, if you all keep tabs on sales on the other A series models, I am game in buying and testing the others.
Not sure when the next JBL/Harman sale will be for the Stage A1XX series but it's been on continuous sale for months at Crutchfield and remains on sale there today thanks to a "special purchase." Crutchfield is offering the $500 A190 for $300, the $400 A180 for $240 and the $300 A170 for $180, so slightly more than the best JBL/Harman sale price.
 

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
7,604
Likes
7,313
Location
UK
It's not the FR chart that is for the wrong speaker, it's the assertion that the woofers are in parallel. Isn't the crossover for the Stage 180 that we are now talking about a 2.5 design, suggesting that the second woofer is not simply in parallel with the first? The woofers that we know are in parallel are on the Studio speaker circuit diagram from post 95 and not for this speaker.
I am talking about Stage 180 and I’m not making any assertions. Dennis posted above that the woofers are connected in parallel. Hence, my question about why the FR difference remains.
 

KMO

Addicted to Fun and Learning
Joined
Aug 9, 2021
Messages
629
Likes
901
I am talking about Stage 180 and I’m not making any assertions. Dennis posted above that the woofers are connected in parallel. Hence, my question about why the FR difference remains.
You started talking about the schematic - for a different speaker - in post 95, wrongly saying that only one of the woofers had the inductor. Presumably at the time you thought it was the A180's schematic.

People corrected your misreading of that schematic - of a different speaker - to point out that they were actually connected in parallel.

No-one is saying the woofers in the Stage A180 are connected in parallel.

Have you figured out that the schematic is not for the A180 yet?
 

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
7,604
Likes
7,313
Location
UK
You started talking about the schematic - for a different speaker - in post 95, wrongly saying that only one of the woofers had the inductor. Presumably at the time you thought it was the A180's schematic.

People corrected your misreading of that schematic - of a different speaker - to point out that they were actually connected in parallel.
I now realised my error. I am sorry and thank you for bearing with me. I apologise for confusing the thread.

I do however still keep my reservation of paralleling the woofers and allowing them to work up to 2000Hz.
 

Dennis Murphy

Major Contributor
Technical Expert
Joined
Mar 17, 2020
Messages
1,071
Likes
4,535
I now realised my error. I am sorry and thank you for bearing with me. I apologise for confusing the thread.

I do however still keep my reservation of paralleling the woofers and allowing them to work up to 2000Hz.
I have reservations about paralleling woofers that are placed this far apart, but I have more reservations about trying to pull off a 2.5 design at an affordable upgrade. I've done 2.5's on consignment, and they're very tricky--it's way too easy to end up with midrange problems. But I'll listen to what I have carefully and take vertical measurements--if I think the vertical lobe(s) are a serious audible problem, I'll sweep the design into a corner with a lot of other efforts.
I would take issue with your statement that lobing explains why we don't see dual midranges in speakers. We see them all the time--they're called mtm's, and the tweeter that separates the two mids makes the lobing issue even more difficult even allowing for the higher crossover point on some mtm designs. But an mtm can provide very clean sound despite the irregularities in the vertical radiation. Some would claim the cancellation is an advantage in reducing ceiling bounce. But that's an unsettled issue.
 
Last edited:

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
7,604
Likes
7,313
Location
UK
I have reservations about paralleling woofers that are placed this far apart, but I have more reservations about trying to pull off a 2.5 design as an affordable upgrade. I've done 2.5's on consignment, and they're very tricky--it's way too easy to end up with midrange problems. But I'll listen to what I have carefully and take vertical measurements--if I think the vertical lobe(s) are a serious audible problem, I'll sweep the design into a corner with a lot of other efforts.
Thank you for listening.
I would take issue with your statement that lobing explains why we don't see dual midranges in speakers. We see them all the time--they're called mtm's, and the tweeter that separates the two mids makes the lobing issue even more difficult even allowing for the higher crossover point on some mtm designs. But an mtm can provide very clean sound despite the irregularities in the vertical radiation. Some would claim the cancellation is an advantage in reducing ceiling bounce. But that's an unsettled issue.
I wasn’t talking about d’Appolito design but about two parallel mid drivers on top of each other (like the woofers are in your design). I don’t think they exists since the days of throw the speakers on a baffle design of the 60s.
 

Dennis Murphy

Major Contributor
Technical Expert
Joined
Mar 17, 2020
Messages
1,071
Likes
4,535
Thank you for listening.

I wasn’t talking about d’Appolito design but about two parallel mid drivers on top of each other (like the woofers are in your design). I don’t think they exists since the days of throw the speakers on a baffle design of the 60s.
I don't see the distinction--you have lobing either way. The mtm has special properties that make it attractive, at least in theory. My point is that you can't rule a design out as unacceptable just because there are vertical lobing issues.
 

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
7,604
Likes
7,313
Location
UK
I don't see the distinction--you have lobing either way. The mtm has special properties that make it attractive, at least in theory. My point is that you can't rule a design out as unacceptable just because there are vertical lobing issues.
The cleverness of d’Appolito is that there’s no loping. Loping is cancelled at the crossover frequency because the loping that will happen with either driver cancel each other due to the unique layout. This doesn’t happen when you place the drivers like they are on this speaker.

d’Appolito’s AES paper explains this well.
 
Last edited:

DSJR

Major Contributor
Joined
Jan 27, 2020
Messages
3,312
Likes
4,425
Location
Suffolk Coastal, UK
Smaller floorstanders in MTM style tended not to work for me at least. One had to sit on the floor to get the most high frequencies. Maybe that was cruder crossover slopes causing cancellations? Taller column speakers obviously work better as the tweeter can be set higher.
 

Dennis Murphy

Major Contributor
Technical Expert
Joined
Mar 17, 2020
Messages
1,071
Likes
4,535
The cleverness of d’Appolito is that there’s no loping. Loping is cancelled at the crossover frequency because the loping that will happen with either driver cancel each other due to the unique layout. This doesn’t happen when you place the drivers like they are on this speaker.

d’Appolito’s AES paper explains this well.
That's only if you can conform to the extremely close spacing specified in the original paper. That's almost never possible, and you get cancellation issues with MTM's virtually all of the time, hence the objections to MTM center channel speakers. D'Appolito's only commercial speaker--the Thor--didn't meet the spacing requirements and used a 4th order LR crossover rather than the originally dictated 3rd order Butterworth. But none of this matters if the speaker sounds OK. We'll see whether my mod stands up to careful scrutiny.
 

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
7,604
Likes
7,313
Location
UK
But none of this matters if the speaker sounds OK. We'll see whether my mod stands up to careful scrutiny.
That is true but for who or by whom? :)

Hence, the importance of objective measurements.
 

cavedriver

Addicted to Fun and Learning
Joined
Jul 10, 2020
Messages
629
Likes
602
Location
Maryland, USA
That's only if you can conform to the extremely close spacing specified in the original paper. That's almost never possible, and you get cancellation issues with MTM's virtually all of the time, hence the objections to MTM center channel speakers. D'Appolito's only commercial speaker--the Thor--didn't meet the spacing requirements and used a 4th order LR crossover rather than the originally dictated 3rd order Butterworth. But none of this matters if the speaker sounds OK. We'll see whether my mod stands up to careful scrutiny.
Dennis,

If my information is correct I think D'Appolito designed several commercial speakers for Snell while he was there. The "Illusion" speaker written up in this article from Stereophile indicates he also used a 4th order LR crossover for this one, and does not clarify whether he was able to achieve the target driver spacing or not. The vertical off-axis measurements suggest a significant low develops around 2 kHz but the reviewer describes the speaker as fairly tolerant in the vertical axis. Hard to trust Stereophile either way but a data point for discussion nonetheless. Perhaps the Illusion is basically the Thor MTM configuration with 2 10" woofers in a larger cabinet. No disrespect to D'Appolito but the Stereophile review is not the feedback I would want to hear for a $50k speaker.
 
Top Bottom