Yamaha NS-6490 3-way Budget Speaker Review

[richardbruce]

"Can anyone tell me if these crossovers are appropriate? Yamaha says the factory "crossovers" are at 2.5kHz and 8kHz. The ones I'd like to install are 850kHz and 4500kHz"

First lets clear this, does yamaha say 2.5khz and 8khz and you say you like to shift to 850Hz and 4.5 khz???

Couse if you like to do this, you max power gets reduced.

About that change in the xover maybe you better ask in the diy corner.

Yes to the question about Yamaha's factory crossover specs.

Yes, those are the frequencies of the crossovers I'm looking at.

I'm not worried about the power right now. I almost never push my speakers hard, especially if I'm unsure how much overhead I have. Yamaha specs state these loudspeakers are rated for 140w peak and my amp is 100wpc. But I don't use more than about 10% of that in my apartment. Neighbors would complain. Hell, they hear my 15w guitar amp!

I'll check out the diy corner. I'm also looking at various crossover calculators and punching in some numbers.

Thanks!

 

[richardbruce]

"Can anyone tell me if these crossovers are appropriate? Yamaha says the factory "crossovers" are at 2.5kHz and 8kHz. The ones I'd like to install are 850kHz and 4500kHz"

First lets clear this, does yamaha say 2.5khz and 8khz and you say you like to shift to 850Hz and 4.5 khz???

Couse if you like to do this, you max power gets reduced.

About that change in the xover maybe you better ask in the diy corner.

Also I have to believe that those large resistors, especially in parallel (as show in the YouTuber's crossover) are to soak up some of that power and reduce the power to the drivers. Does that differentiate these crossovers from a "passive" crossover network? Just curious...

 

[No. 5]

I know this is an old thread but I've had a set of these cheap speakers for almost 3 years and I'd like to improve them as much as possible without replacing the drivers. I plan to install a "real" crossover then pack 'em with... something to reduce the resonance. Can anyone tell me if these crossovers are appropriate? Yamaha says the factory "crossovers" are at 2.5kHz and 8kHz. The ones I'd like to install are 850kHz and 4500kHz. I figure moving more of those mids to the mid and highs to the tweeter will clean up the muddiness. Anyone?

First off, let me say that's a really commendable idea. I did the same thing years back and that project ended up being one of the most informative things I ever did in my audio journey (the speakers I used eventually ended up sounding much better too ).

If I had a pair of NS-6490's on hand, I'd probably be able to be more helpful to you, but I'm happy to give what help I can.

For starters:
If any of the resonances are in the cabinet volume, I've used Rockwool to good effect for that in the past. Acoustic foam should work too. I'll typically just fill the cabinet, but that has the potential of reducing bass response, so you might need to experiment since these are already tuned flat.

For adding new crossovers, you absolutely need to be able to measure the impedance of the raw drivers at the very least, and measuring their acoustic response is also extremely recommended.

 

[tomtoo]

Also I have to believe that those large resistors, especially in parallel (as show in the YouTuber's crossover) are to soak up some of that power and reduce the power to the drivers. Does that differentiate these crossovers from a "passive" crossover network? Just curious...

Did not see the video.
But no caps, inductors, resistors are all parts of passive crossovers.

 

[richardbruce]

Did not see the video.
But no caps, inductors, resistors are all parts of passive crossovers.

And the purpose of large low-resistance high-wattage ceramics ? Again, I'm thinking power soak.

 

[No. 5]

Based on Amir's measurement of these, one of the biggest things to make these speakers sound better would be to bring down the tweeter and mid's level, that's what those resistors are for. Not sure they need to be 10 Watt, though.

Edit: the passive crossover on these as it comes from the factory is just a first order high-pass on the tweeter and mid. That's what the two capacitors are. They are probably there more for protecting those drivers than shaping the response.

 

[richardbruce]

Based on Amir's measurement of these, one of the biggest things to make these speakers sound better would be to bring down the tweeter and mid's level, that's what those resistors are for. Not sure they need to be 10 Watt, though.

I thought so - thanks! Again, just spitballing here. Appreciate your helpful comments.

 

[tomtoo]

Also I have to believe that those large resistors, especially in parallel (as show in the YouTuber's crossover) are to soak up some of that power and reduce the power to the drivers. Does that differentiate these crossovers from a "passive" crossover network? Just curious...

And the purpose of large low-resistance high-wattage ceramics ? Again, I'm thinking power soak.

See i dont know the cirquet. Changing a xover has many effects. It can change FR, directivity, power handling. And iam far away beeing a x-over expert. I like to help as good i can, and i would suggest open a thread in the diy corner, there are the people that use simulations and so on.

 

[richardbruce]

One more post and 2 photos then I'll head over there and research other sources of info. The woofers don't look too bad. Large 3.5" voice coil and magnet.

 

[No. 5]

I thought so - thanks! Again, just spitballing here. Appreciate your helpful comments.

Happy to help. I just glanced at that video, but it looks like it cost more than I would want to spend to improve a $99 speaker. If you are interested in new crossover's, I'd suggest making some measurements of what you have and going from there.

...i would suggest open a thread in the diy corner, there are the people that use simulations and so on.

Good suggestion! Keep this thread from getting too cluttered.

 

[AdamG]

One more post and 2 photos then I'll head over there and research other sources of info. The woofers don't look too bad. Large 3.5" voice coil and magnet.

As promised @richardbruce has created a separate thread to further discuss this branching topic:

Yamaha NS-6490 improvement project

Yamaha NS-6490 improvement project thread from https://www.audiosciencereview.com/forum/index.php?threads/yamaha-ns-6490-3-way-budget-speaker-review.17042/page-5#post-1227222 I was asked to move this discussion to the DIY but the thread contains background info. Please read it and listen to the...

www.audiosciencereview.com

 

[Chris Kelly]

I have seven of these in my 7.1 system. For years in my audio/vidio / home theatre journey, I preferred bassy overtones. However, once I started enjoying the intimacy of headphones and discovered that bassy overtones take away from lifelike quality when watching shows and movies, I eventually wound up with the Sennheiser HD 560S headphones six days before this post. I have reservations about applying EQ because I don't know if my Pioneer Elite SC-81 audio/video receiver's EQ is taking place in the analog path or in the digital path. If it's taking place in the digital path, this might decrease the resolution when playing DSD material if it's being converted to 96KHz or lower, as opposed to DSD or 176.4KHz PCM. So a few days ago, I was considering getting smaller speakers and giving up low frequency coverage for a more lifelike sound. However, as long as shows and movies are recorded at 48KHz, I decided to give EQ, a known enemy of high-res audio, a try. So after working with the equalizer in my AVR, I got the best results when making a cut in the 250Hz area.

 

[Chris Kelly]

I was using these on the floor for five months. Almost two weeks ago, I removed my TV, put the left, center, and right channel speakers where the TV was. I currently have my 15.6" OLED laptop two shelves above the speakers and am using its HDMI output for audio. Being that I can't place the side speakers where I want to, I am using two NS-6490s as stands for the ones I'm using as rear surrounds so they're off the floor. With all these speakers about a foot and a half off the floor, I achieved better results and was able to disable EQ and go back to my AVR's Pure Direct mode. According to amirm, I understand that one of the flaws with this model is that all three drivers bleed into each others' ranges. But how badly does this affect the overall sound curve of these speakers when listening to them as a whole? I do like the wide audio spectrum coverage of this model. Yamaha claims they only go down to 45Hz. Without EQ, I can get them to go down to 30Hz. If I raise the volume to an uncomfortable level, I can almost get them to go down to 25Hz. Except for subwoofers, I don't remember a bookshelf speaker which can reach down to 30Hz at normal volume. Also, I think the acoustic suspension design makes the bass more authentic than a bass reflex design. I think these speakers are too large to be called bookshelf speakers, and too small to be called floor speakers. I don't remember hearing anything better than these when installed properly.

 

[Chris Kelly]

What's the secret behind these unusually compact three-way speakers? Speakers are supposed to be designed with their components installed vertically. These speakers are designed with their woofer on the bottom, and above their woofer, a midrange driver on the left and a tweeter on the right. If you plan on background listening, this would less likely be a problem. However, for critical listening, this design flaw results in everything being placed towards the left when used as front and center speakers, slanted from back to front when used as side speakers, and towards the right when used as back speakers. I did not think this was as serious of an issue until I reconfigured my room so I could properly place my TV and speakers, including better separation between the speakers. Moving forward, I am now using these speakers as stands for my smaller Yamaha NS-AP5700BLF speakers, each with a vertically installed 6.5" woofer and 0.75" tweeter. Their bass coverage is almost as good, and their treble coverage might be a little better with the slightly smaller tweeter. They do not include a midrange driver. However, there might be such an insignificant gap between the upper tones of their woofer and lower tones of their tweeter that a midrange driver might not be necessary. I would imagine that their low price results from their low nominal power rating and veneer finish. However, I do not listen loud enough for my ears to ring after I am finished listening. So I don't think the nominal power rating would be a serious issue for me. The NS-AP5700BLF are only available through Yamaha's parts department. I wish Yamaha would release the NS-AP5700BLF speaker as an actual product.

 

[YSC]

What's the secret behind these unusually compact three-way speakers? Speakers are supposed to be designed with their components installed vertically. These speakers are designed with their woofer on the bottom, and above their woofer, a midrange driver on the left and a tweeter on the right. If you plan on background listening, this would less likely be a problem. However, for critical listening, this design flaw results in everything being placed towards the left when used as front and center speakers, slanted from back to front when used as side speakers, and towards the right when used as back speakers. I did not think this was as serious of an issue until I reconfigured my room so I could properly place my TV and speakers, including better separation between the speakers. Moving forward, I am now using these speakers as stands for my smaller Yamaha NS-AP5700BLF speakers, each with a vertically installed 6.5" woofer and 0.75" tweeter. Their bass coverage is almost as good, and their treble coverage might be a little better with the slightly smaller tweeter. They do not include a midrange driver. However, there might be such an insignificant gap between the upper tones of their woofer and lower tones of their tweeter that a midrange driver might not be necessary. I would imagine that their low price results from their low nominal power rating and veneer finish. However, I do not listen loud enough for my ears to ring after I am finished listening. So I don't think the nominal power rating would be a serious issue for me. The NS-AP5700BLF are only available through Yamaha's parts department. I wish Yamaha would release the NS-AP5700BLF speaker as an actual product.

Er... I am not sure I got what your question is... this design is basically a disaster... so there's no actual secret to it..

 

[Chris Kelly]

Er... I am not sure I got what your question is... this design is basically a disaster... so there's no actual secret to it..

Er... I am not sure I got what your question is... this design is basically a disaster... so there's no actual secret to it..

I thought I'd open my latest review update with a riddle, which I answered by explaining the horizontal midrange driver and tweeter.

 

[YSC]

I thought I'd open my latest review update with a riddle, which I answered by explaining the horizontal midrange driver and tweeter.

Sorry bro I still don’t understand… with that uneven a frequency response with tons of resonances the speaker is seriously flawed to say at least… I re read your post with regards to placement, it’s just as expected as the directivity is such a mess that basically a pin point is where the sweet spot located at, yet even at that spot it will still be overly bright and with tons of resonances. I won’t remotely call it a secret personally. From the spin it did looked like they somehow are aiming for in room flat tuning though

 

[Chris Kelly]

After doing several A-to-B comparisons, I discovered that the placement issue I was experiencing may have been caused by different acoustical characteristics throughout my home theatre area. In order for my posts to have integrity, I post such findings upon discovering them.

 

[No. 5]

Speakers are supposed to be designed with their components installed vertically. These speakers are designed with their woofer on the bottom, and above their woofer, a midrange driver on the left and a tweeter on the right.

You know, if you rotate them 90 degrees you end up with vertical tweeter/mid placement, like a Klein & Hummel O300 or Dynaudio LYD 48.

Not that it'll make the NS-6490 sound like those...

 

[CrankyElbow]

I had a pair of these acquired cheaply used... they were tolerable as "garage speakers", but were spectacularly fragile and the woofers were blown in average listening of bass heavy electronic music. One of my greater disappointments in audio - interesting to see this test objectively reveal why. The mid and tweeter drivers are absolutely shrill... the woofer was passable, with decent bass response - but "enjoying" it with bass heavy music proved too much of an ask.
Since then I've tinkered with them, changing all the drivers... building internally an enclosure for a 3" "full range" driver (PVC pipe) and running the 8" driver as a "subwoofer" in a bi-amped configuration showed great promise (fun project) - but the same drivers in a subwoofer/satellite config would be much more flexible and the crappy cabinet construction is extremely limiting and ultimately makes seriously upgrading these a waste of time.
Right now I'm running them 2 way with visaton woofer/dayton titanium tweeter (still biamped) until I decide on an enclosure design to replace them... the sound is tolerable.
If I was to modify these "from the factory" for as little work/money as possible - I'd do the PVC enclosure behind the midrange, swap out the midrange for a 3" "full range" that better matched the sensitivity of the woofer (easy to accomplish with lower xover points and a little EQ), and build a more robust crossover, one that reinforced the highest frequencies that most "full range" drivers do not fullfill (say 300hz/10khz)... this could easily be done under $50 utilizing any of many 3" drivers that generally provide very nice midrange resolution.