Polk T15 Bookshelf Speaker Review

[Koeitje]

Making fun of people who can't afford expensive audio equipment? How very audiophile of you.

You stay classy ASR.

Those people should buy second hand. If you don't have money but want good sound you don't buy new.

 

[mt196]

@amirm Any chance to have some wharfedale diamond series measured?

 

[wwenze]

Lots of buyers would give a 5 star rating because that is the first bookshelf speaker they own and it would still be miles better than the whatever crap they have been using.

Imma go comparing this with the Micca measurements now, is the Micca really a better deal...

 

[Gedeon]

Maybe opening the box and swapping the +- in woofer could mitigate the cancelation issue...

Or I'm saying something dangerous/stupid ???

 

[tomtoo]

Ideal thought, would reversing the polarity on the tweeter help?

That would be interesting.

 

[edechamps]

@amirm I can't find the measurement raw data zipfile. Did I miss it?

 

[tomtoo]

Is it cheaper to produce speakers with these odd off-axis characteristics that somehow, somewhat correct on-axis performance? IIRC Audioholics has pointed out similar behavior in some budget Dayton's. Are they really, purposefully producing bad speakers based solely on the assumption Joe Sixpack's going to use them wildly off axis, or is that just a convenient dumb luck excuse?

Not an expert. But this is imo a poor x-over. I think they just use a capacitor for the tweeter and let the woofer run full. Would be interesting if some x-over mod could be made cheap. So Joe Sixpack could use them better on-axis? What do the experts say?

 

[SimpleTheater]

Clearly explained by Amir at the end of his review - you apparently did not read through to the end.

I stop after I see the Pink Panther. Everything else is just noise.

 

[tomtoo]

Those people should buy second hand. If you don't have money but want good sound you don't buy new.

And how should you know that the old used thing is better than the actuall by @amirm tested?

 

[pjug]

Personally, I wouldn't even trust this type of keyhole mount (below), steel reinforced and screwed keyhole on the back of a Dali Zensor 1. They are too heavy for this long-term, especially in a humid climate.

I had a fairly cheap pair of speakers with threaded inserts on the back for wall mounting. They hung on a wall for a few years until one day one of them fell down when I happened to be in the room. The glue on the MDF panels failed and most of the speaker came tumbling down. When I called the company to let them know about it they couldn't have cared less since these were out of warranty. They shrugged off my concern that hanging these could hurt somebody.

Now I would not suspend from the back any speaker that does not have a wraparound kind of cabinet structure. I would make small shelves for MDF speakers going on the wall.

 

[Milesian]

Still scratching my head as to why you would waste your time, resources and considerable expertise on a speaker which the price point alone should indicate is going to be heavily compromised.

 

[CJ Miller]

When the frequency response chart looks like a Fun roller coaster you usually have a problem.

 

[Prana Ferox]

Lots of buyers would give a 5 star rating because that is the first bookshelf speaker they own and it would still be miles better than the whatever crap they have been using.

Internet 5 star ratings mean it met expectations, that's all. Anything below a 5 means obviously defective or something wrong with the purchase process. "It arrived on time, it wasn't damaged, I hung it on my wall, it made sound" -> 5. Has nothing to do with being an exemplary product.

Not an expert. But this is imo a poor x-over. I think they just use a capacitor for the tweeter and let the woofer run full. Would be interesting if some x-over mod could be made cheap. So Joe Sixpack could use them better on-axis? What do the experts say?

It has an inductor on the woofer side. Still, very basic.

That being said, that little 3/4" tweeter needs to cross high. Compare and contrast it to Scott Sehlin's Helium, which also has a 3/4" tweeter. He crosses at 5khz and the C-t-C of the drivers is 2.7" - exactly the wavelength of 5khz, aiding integration. I can't exactly tell what this Polk's c-t-c is but it's at least 5" if not more. 5" is 2.7khz, which means whatever the actual crossover is (somewhere between 3 and 6khz) the drivers are too far apart and you're going to get lobing, just as the spinorama shows. I don't know if a modded crossover can really fix that; you'd have to push the frequency way down and I doubt the tweeter can take it.

 

[tomtoo]

The Polks are at 108€/pair at amazon.de. Thats 9€ more expensive than the canton 206.

https://www.amazon.de/Canton-206-Ko...aar/dp/B005MYQ7E2?ref_=mw_olp_product_details

Realy would like how they measure. It's a well known Brand and fu**ing cheap. Do they all suffer the same from poor x-over? This priceregion could give some baseline for performance. I think it's science to ask, have cheap speakers to perform cheap? Or could they with a little bit more brain invested not at least perform decent?

 

[Hugo9000]

The RS Pro LX5 with linaeum tweeter was measured by stereophile.

https://www.stereophile.com/content/radioshack-optimus-pro-lx5-loudspeaker-measurements
This is with drinking straws damping the port (an essential modification) in the lower trace.
View attachment 51918
I'm afraid they'll fall down off axis however.
View attachment 51919
View attachment 51921

I bought a pair of these for $55 during a huge sale at Radio Shack back in the day. I briefly tried them on their own as a stereo pair and didn't care for them that way. I then drilled holes in the bottom and hung them upside down from the ceiling (grilles flipped so it looked like I was using them as intended haha) and pointed toward the listening position for rear surrounds in my first home theater setup! They worked well enough for that, and $55/pair was impossible to beat lol.

 

[Poseidons Voice]

Headless panther is my vote, irrespective of price. Serious directivity mismatch here and the direct on axis response gets a solid “F.”

 

[LostOne___]

...and the search for the Khadas Tone Board/JDS Atom of speakers continues, alas...

But once Amir finds it...oh man, that is going to revolutionize the field.

 

[mhardy6647]

I stop after I see the Pink Panther. Everything else is just noise.

The only problem with the Panther Scale is that the resolution is fairly low. I am not even sure if it is linear or logarithmic -- so I like to look at the data and commentary and work out the correlation.

I'm going to take a guess and suggest that it could be similar to what drug companies do. You try to make a product that has efficacy in a certain area, yet in your testing, you find it doesn't work as intended. However, you see a 'side effect' that can be monetized, so your time and money wasn't all wasted after all. In some instances, the 'side effect' ends up being more valuable than if the product had worked as initially intended/designed/hoped. lol

Y'all probably know this, but that's how the world got Viagra. Pfizer was testing a drug for cardiovascular indications, but the test subjects in the clinical trials reported some interesting side-effects. Couldn't find a really good synopsis outside of the peer-reviewed literature (that costs $ or requires,e.g., academic library access credentials to read), but here's an example: http://resources.schoolscience.co.uk/pfizer/viagra/viagch5pg1.html

For $70 I would probably buy a set of old Polk monitors... They go cheap and sound good. Probably couldn't hang one on the wall though.

Well... if you got lucky, perhaps you could find a pair of these. (For the record, I am still lookin' for a pair).

Full disclosure: I am a long-time Polk fanboy and have owned a pair of their early Monitor Series Model 7A ("Monitor 7A") since 1978.

 

[tomtoo]

Internet 5 star ratings mean it met expectations, that's all. Anything below a 5 means obviously defective or something wrong with the purchase process. "It arrived on time, it wasn't damaged, I hung it on my wall, it made sound" -> 5. Has nothing to do with being an exemplary product.



It has an inductor on the woofer side. Still, very basic.

That being said, that little 3/4" tweeter needs to cross high. Compare and contrast it to Scott Sehlin's Helium, which also has a 3/4" tweeter. He crosses at 5khz and the C-t-C of the drivers is 2.7" - exactly the wavelength of 5khz, aiding integration. I can't exactly tell what this Polk's c-t-c is but it's at least 5" if not more. 5" is 2.7khz, which means whatever the actual crossover is (somewhere between 3 and 6khz) the drivers are too far apart and you're going to get lobing, just as the spinorama shows. I don't know if a modded crossover can really fix that; you'd have to push the frequency way down and I doubt the tweeter can take it.

Thx!

 

[Hifihedgehog]

Preference Rating
SCORE: 11.0
SCORE w/ ideal subwoofer: 11.0

What are you talking about? It got straight 11’s.

No way it scored so high.