Are the BK Gemini II subwoofers good for music?

[Deleted member 910934]

I don’t know if I’m too late for you, but I use two BK Gemini IIs in a stereo only system and I think they are very good. They replaced a much larger ported Tannoy subwoofer that took many years of repositioning and adjusting to get it to blend. In contrast the BKs took minutes…

I use them with Naim/Arcam electronics and Tannoy or Piega Floorstanding speakers depending on what I fancy. The subwoofers are wired in stereo (line level) and positioned just behind the speakers to minimise phase issues - I have tried alternative positions but despite the idea that bass is supposed to be difficult to locate, positioning the subs away from the speakers to where bass output was greatest also seemed ’dislocate’ the sound image - at least to my ears so I prefer them next to the speakers - remember this is a 100% music only system - HT applications may work best with bass spread around the sound field.

I like the Geminis because of how they sound, but also because of how easy they are to set up and the digital display on the amplifier really helps with this - the crossover can be set accurately to every 3hz or so. To my ears the 10inch driver seems plenty quick enough and the 150 watt amp, for music use, has sufficient power - the display has VU metres via LEDs and they rarely flash at all - the lowest of the indicators is 30 watts. One caveat is that for HT use I also use another Gemini II in another system and when watching films such as Tron Legacy, the VU metres really do light up! The stereo only BKs are used in a room 6.5 X 3.5 metres.

I know they are different beasts but music use I prefer my smaller sealed dual BKs to the single ported 15inch Tannoy I had before. Much less boomy and easier to integrate. In fact I am contemplating adding two more and stacking them as per the REL 4 pack/6pack systems - the advantage of this approach is I could set individual gain/crossover/phase for each unit in the stack (can’t do that with the Double Gem - 1 amp for 2 drivers) and I could even fire the top unit upwards, giving an extra height dimension to the bass output. This would have the added benefit of evening-out the bass response on the vertical plane.

Regards
Alex

Hi Alex,

Thanks for the reply. No, its not too late at all. I am still considering getting 2 BK Gemini II subwoofers, but have put it on hold while I work out another issue. You post is very interesting, as some people have suggested running 2 subs requires DSP. Other sources suggest that integrating a subwoofer with other speakers well, without DSP, is difficult, even impossible. My own intuition was to use to small sealed subs and place them near the speakers, one on each side, to act as a sort-of "extra driver", crossed over at the point where the bass of the main speakers start to nose dive and matching the volume as best as I can by ear. Having nearly given up on this idea, thinking it impossible, your post makes me consider giving it a go. So, thank you...

Kind regards...

 

[Alex P79]

My own intuition was to use to small sealed subs and place them near the speakers, one on each side, to act as a sort-of "extra driver", crossed over at the point where the bass of the main speakers start to nose dive and matching the volume as best as I can by ear. Having nearly given up on this idea, thinking it impossible, your post makes me consider giving it a go

That is pretty much exactly what I do - I set the crossover of each sub at the roll-off point of the main speakers and then fine tune crossover point and volume from there - I view them as bass extenders to the main stereo pair more than anything else. When set up correctly the benefit to LF is clear but more critically, they help with sound-staging and image depth etc. It used to be very difficult to set up the old sub this way but it is a cinch with the two BK units. Which leads me to…

You post is very interesting, as some people have suggested running 2 subs requires DSP. Other sources suggest that integrating a subwoofer with other speakers well, without DSP, is difficult, even impossible

On the contrary, from my experience, setting up two smaller subs positioned near the corresponding full range speaker is much simpler. Indeed before I tried this and using the old Tannoy sub, I would have agreed that DSP would be a great idea. However, I no longer do. I do understand the use of DSP to even out room response from a single unit and in HT application where the likes of room correction helps with set up when there is so much LF content/energy. Perhaps the issue that people have is having a subwoofer that is ’boomy’ (read ported) and/or too much for the room, such that it overdrives the room at certain frequencies. I believe that this combination was the case with my previous sub.

 

[password1]

I've used both the xls200 and gemini 2.

The Gemini 2 is very good for music. It will play loud and is faster and punchier but the xls200 is slightly deeper, not an issue if the music you play doesn't have very deep bass.

The cabinet has the same build quality. I prefer the amp on the Gemini 2 as it feels more premium and has a digital display and Led lights to indicate how much power it's pumping out, whereas the amp on the xls200 feels more old school and cheap.

 

[Paul7777x]

The amp on the XLS is far from ‘cheap’.

It has twice the output of the Gemini and a considerable current advantage. BK are known globally for their bullet proof professional power amplifiers.

Having had both the Gemini and the XLS too, twice with a couple of years between, I can hardly agree with your conclusion.

I also have an XLS200 now.

The Gemini is a great sub for small to modest output speakers, but the XLS is an altogether more serious subwoofer

As well as the better amplifier it also has the seriously specced peerless XLS 10” driver. Again, a notable upgrade on the Gemini’s.

For the extra £100 it’s not a real choice if the money is available.

 

[Deleted member 910934]

The amp on the XLS is far from ‘cheap’.

It has twice the output of the Gemini and a considerable current advantage. BK are known globally for their bullet proof professional power amplifiers.

Having had both the Gemini and the XLS too, twice with a couple of years between, I can hardly agree with your conclusion.

I also have an XLS200 now.

The Gemini is a great sub for small to modest output speakers, but the XLS is an altogether more serious subwoofer

As well as the better amplifier it also has the seriously specced peerless XLS 10” driver. Again, a notable upgrade on the Gemini’s.

For the extra £100 it’s not a real choice if the money is available.

Thank to you both for your replies. It's interesting to see such different opinions about the same item. I guess the best thing for me is to have a listen for myself. Sadly, the forward firing XLS200 is currently unavailable. The down firing option is, but perhaps it makes not difference.

My impression from having a look at BK's website is they they advertise the quality of the peerless driver in the XLS200, but make no mention of it on the Gemini 2, which leads me to believe the Gemini uses a cheaper, less marketable ("impressive") driver. At nearly double the power, and only a small extra cost, it is tempting to get the XLS200. They are more or less the same size, so placement won't be much different. The other curiosity is that BK provide a -6db frequency response measurement for the XLS200 (a suspiciously low 17Hz...perhaps they stuck it in the corner of a cupboard when measuring this?) but not the Gemini 2. I assume the figure wasn't as impressive as their other products, so they left it off.

Personally, I don't need earth-shaking bass. I was just considering something to fill in the gap between about 28Hz and 60Hz, or 28Hz and 40Hz, depending on which of the two systems I pair it with. I am likely to think the Gemini 2 will be fine, and a bit cheaper, as I would get the Black Gloss version to match the QA Concept speakers.

Perhaps I will ask BK what they think? I have read they are quite helpful on the phone...

 

[password1]

BK don't specify what the driver in the Gemini 2 is but it's good enough for them to make the Double Gem and claim to give good performance and an alternative to the platinum.

I wouldn't base your decision on wattage. You'll never run the sub at maximum. For music listening the LED indicators on Gemini 2 dont go beyond 2 lights much. All of the LEDs only flash during big explosions for a few seconds at a time when you're watching a.movie at loud.volumes.

I.agree the peerless driver is better, it has a thicker rubber surround, more excursion, the xls200 has a more powerful amp but it's old school and a basic very old class AB design. The Gem 2 driver is a little tighter. Both good at their price points.

 

[Deleted member 910934]

I.agree the peerless driver is better, it has a thicker rubber surround, more excursion, the xls200 has a more powerful amp but it's old school and a basic very old class AB design. The Gem 2 driver is a little tighter. Both good at their price points.

That sounds good. I am not looking for DEEEEP bass, as I am only listening to music, and most of my music is rock, classical or acoustic. If I can hear the lowest notes on a piano and bass guitar, I will be happy. Don't listen to organ music, so my windows don't need rattling

The idea of a tight, fast subwoofer with less bass appeals more than a deep, bass mining sub. Plus, the gloss black version of the Gemini 2 is only £50 more than the wood versions. Only £300. Seems like a good deal, since I plan to get two.

Thanks for the advice guys.

 

[password1]

Each model in the BK range isn't that much more than the model below.

The Double Gem and Platinum p12 arent that much more than the Xls200.. Then the xls400 isn't that much more than the p12. Then the Mono and mono plus isn't that much more than the xls400.

Whichever model you go for they are all well built cabinets.

 

[luiscardoso88]

At one point I had a BK Gemini II connected to an amplifier that was also powering a pair of Monitor Audio Silver 2 (rated to 40Hz @-6 dB) and it didn’t seem to go any lower than the speakers. At 30Hz I couldn’t hear anything unless I turned everything up to 11.

But it could’ve been the room, I don’t know. I wish I hadn’t sold it because it would help my ATCs, I’m sure.