[CCBios]

I have a pair of the Wharfedale Denton 85th. Great speakers, full sounding and musical but female voices can be boxy sounding (and veiled at low volume). What mods could improve this? No Rez from GR research? What else can make the voices sound more natural besides reducing box resonances? I'm driving these with a Rotel A12 (rather neutral, class AB 60 watts/ch integrated amp).

Thanks
CCBios

[FullRangeMan]

Welcome 
What mods could improve this?
What else can make the voices sound more natural besides reducing box resonances?
Removing the xover certainly will help.

[richidoo]

Removing the xover certainly will help.

How? 

female voices can be boxy sounding (and veiled at low volume). What mods could improve this?

Cure the boxy voices tonal problem by experimenting with the speaker placement distance to the front walls. The front wall reflection is the culprit. Start by placing the tweeter diaphragm 24" from the front wall. Move in and out by 1/2" increments. Find compromise between too much bass (too close to wall) and too much tonal blur (too far from wall.) If you have small woofers you can tolerate going closer to wall and getting clearer mids. Big woofers too close to the wall for the clear mids will make the bass too loud. The blur (boxyness) is caused by phase interference. SBIR (Speaker Boundary Interference Response) affects both amplitude and phase as heard at the listening position, and the frequency band that's affected by SBIR is proportional to the distance to the front wall. This shifted-phase tonal effect is particularly annoying at midbass to low mid frequencies and most obvious on vocals.

The "veiled at low volume" problem is caused by low acoustic impedance at low volumes. The small woofers lose grip on the air when they are moving at low speed due to low volume. They come to life when cone speed is increased at higher volumes. Large woofers give more detail at all volumes, and remain loud enough to feel satisfying even at very low volumes. Speakers with large woofers look "loud" but they actually allow satisfying listening (=good bass) at lower volumes than small speakers.

As for mods, the musicality and fullness attributes you like come partly from the box so I wouldn't mess with that. Good sounding speakers often allow the box to move as a tuning metric. Take away that musicality by stiffening and damping the box vibration and you will get more detail which will reveal the inherent lack of refinement of the inexpensive speakers. The loose box is part of the successful recipe of inexpensive speakers. Hot rodding cheap speakers is a dead end, imo. If you really want more detail then invest in more expensive speakers which will give you more refinement along with the added tonal detail.

[FullRangeMan]

How? 
using a FR driver direct from the amp, no Zobel no notch filter.

[CCBios]

FullRangeMan: thanks for the welcome and feedback. I will have to do some research regarding your “using a FR driver direct from the amp, no Zobel no notch filter” comment, it’s above my head at his point in my journey.

Thanks a million richidoo for your detailed and insightful reply. I played with the distance to the front wall but not in the incremental way you suggested. The Denton 85th has a 6.5 inch woofer, a decent size to work with, I’ll see if speaker placement and room acoustics can also help a bit for the veiled voices at low volume.

I don’t mind it for any instrument but I hate female vocals not sounding natural. There are those planar and open baffle speakers but they have their issues, aesthetics being one of them for me. I’m very puzzled at the cuurent production of all these box speakers with boxy vocals, you would think the manufacturers would have figured this by now, even for sub $1k speakers.

CCBios

[CCBios]

Moderator, could you please correct the 2 typos in my previous post ("this point in my journey") in the first paragraph and "current production" in the last paragraph. I'll check the preview next time...
And of course, delete this current post.
Thanks.

[Phil A]

Welcome!

[ArthurDent]

Greetings & Welcome to AC CCBios       

Moderator, could you please correct the 2 typos in my previous post ("this point in my journey") in the first paragraph and "current production" in the last paragraph. I'll check the preview next time...
And of course, delete this current post.
Thanks.

Not sure in the intro phase, but normally, you should see a "modify" button on the thread screen in the upper right hand corner of your post. Select, then edit as desired, preview or not, then hit save. Hope that helps.

[maty]

There are no images of inside or the crossover. Not frequency response...

You should take apart the woofer and take some pictures.

https://www.wharfedale.co.uk/denton-85/

General Description   2-way vented-box/standmount
Enclosure Type   Bass reflex
Transducer Complement   2-way
Bass Driver   6.5"(165mm) black woven Kevlar cone
Treble Driver   1"(25mm) soft dome
Sensitivity (2.0V @ 1m)   88dB
Recommended Amplifier Power   20-120W
Peak SPL   95dB
Nominal Impedance   4Ω
Minimum Impedance   3.8Ω
Frequency Response(+/-3dB)   45Hz ~ 20kHz
Bass Extension(-6dB)   40Hz
Crossover Frequency   3.1kHz
Cabinet Volume   13.5L
Dimensions H x W x D   340 x 240x (275+12) mm
Net Weight   9.0kg/pcs

[maty]

https://7review.com/wharfedale-denton-85-review/

[maty]

https://www.youtube.com/results?search_query=Wharfedale+Denton+85th

Too much bright! 

[CCBios]

Maty,

The Joe N Tell youtube review is actually very positive (the 85th is currently at the top of his leader board). The 7review mentions brightness but the author found an easy fix: "A 2 Ohm resistor to the treble unit, replacing the bi-wire positive (+) link, gave a measured flat response but a warm-ish sound, whilst a I Ohm resistor was perfect – clear treble but not overwhelming. This gave me the Denton 85th I wanted to hear and is a very simple thing to do (such a tweak can be made to any bi- wirable loudspeaker)."

I didn't use the resistor trick because I listen mostly at moderate to low volumes where the boosted up treble can help. These smallish and cheapish speakers are really fun to listen to at high volumes but I agree that depending on what you listen to, they may need that resistor trick or some equalization to tone down the treble.

So I feel that these speakers have potential, I hope to find some tricks or mods to make female voices sound more natural. Obviously, many speakers could use some help in that regard, it's not a Denton 85th specific problem.

CCBios

[FullRangeMan]

CCBios: a top down expensive renovation will offer a small sound improvement IMO, dont worth the hassle and the speaker no more in original condition.
Please see some FR drivers here, small and big:
http://www.glowinthedarkaudio.com/speakers.html

[charmerci]

Bracing or no-rez won't work if you are not listening at loud levels.

You can try a x-over fix but that's no guarantee to fix this particular problem. Could very well be that this "boxiness" that you don't like is a quality of the drivers themselves.