Bass Reflex Cabinet

조회 수: 5010, 2013-09-16 01:18:20(2013-06-06)

 

Bass Reflect 형 Cabinet  글 참고로 올립니다.

제가 요점을 번역 합니다.

 

위에삽입한 8 inch Speaker 용 소리통 글 이지만 좋은 참고할 정보가 많이 있습니다. 

 

**********************

 

아마도의 지금까지 만드러진 Speaker 의 99.9%는Bass REFLEX 일 겁니다.

Speaker Cabinet 는 오로지 "저음재생"을 위해서  존재하는 것입니다.

 

일반적으로 잘 만드러진 Speaker 통은 클수록 저음이 더 잘 납니다.

 

처음 6.5/8 inch 용으로 만든 통이 1.3cubic ft ( 32T x 10W x 11D inch -grill 포함) 였고 두번찌는 2.8 Cubic ft 로 앞판이 넓은것 38.5T x 14.5W x 11.25D (Series I) 과, 좁은것 38.5T x 12W x 13.75D (MkII) 의 2 가지로 만드렀습니다.

소리는 MKII 가 약간 더 detailed and efficient (정확/심새 하고 효율적) 합니다. MKII 는 통이 1.3 cubic ft 통에 비해서 2배 가까이 돼서 15% 정도 저음특성이 개선 됍니다. 저음 tuning 에 'Twin Port' (구멍 2개) 하고 "a single, very large port" (큰구멍 1개) 2가지 방식이 있습니다. 원래는 구멍 2개였는데 50-100Hz 저음을 더 중요시하는 분들의 요구에 따라서1개로 됀 구멍이  개발 됐습니다.

 

통만드는 재료도 중요 합니다. 합판은 좀 부두러운 소리를 내고 particle board 는 중간이고 MDF 는 재일 섬세/정밀한 소리를 내줍니다. 음원의 질이 높아 질수록  재료도 고밀도로 올라 갑니다.

 

통 내부도 여러기지 Damping 재료로 소리조절을 합니다. Speaker Cone 에서는 소리파를 앞 뒤 모두 똑같이 내 보냅니다. 뒤로 나가는 소리가 통안에서 반사되여 되돌아와 Cone 진동을 방해합니다. Distortion이 발생합니다.

 

일반적으로 앞면만 빼고는 Damping 재료 로 모든 면에서의  반사음을 흡수하도록 합니다.  재료의 선택 사용량 등은 소리를 들어가면서 자기취향대로 조절 합니다.

Bass REFLEX Cabinets

Probably 99.9% of all speakers ever made are Bass REFLEX. Why? In our humble opinion, because they give the best sound! This design produces the most realistic bass and most accurate midrange and treble. So, we strongly recommend the bass reflex cabinet.

A speaker cabinet only exists to do one thing: make bass. Generally speaking, a well designed larger cabinet will always sound better than a well designed smaller one. That's because it's hard to make enough bass to balance with the mids and treble, especially with very detailed speakers like Audio Nirvana. So, over the years, we have developed larger and larger cabinets (as well as larger and larger full-range speakers). However, we haven't forgotten that many customers have space limitations. For them, we have tried to design smaller cabinets that maximize bass output while maintaining the clarity and tightness often missing in small cabinets. 

Our first bass reflex design, for the 6.5 and 8 inch full-range speakers, was called the '1.3'. The external dimensions are 32T x 10W x 11D (with the grill mounted). It's an excellent small floorstanding speaker system. By the way, the name of all of our floorstanding speakers is the volume in cubic feet.

Further development resulted in a larger cabinet we call the '2.8.' There are two main variations. The original 'Series I' has a wide front baffle. The 'MkII' has a thin front baffle. Overall dimensions are approximately 38.5T x 14.5W x 11.25D (Series I) or 38.5T x 12W x 13.75D (MkII). They are close enough in sound quality, that you can pick the one that looks best to you. But the 'Series I' does give a bit softer, smoother, and warmer presentation and might be preferable in 'live' rooms. The 'Mk II' is slightly more detailed and efficient and might be preferable in 'soft' rooms. The greater internal volume (twice as many cubic feet when compared with the '1.3') has resulted in stronger bass response and dynamics (maybe 15%).

And we offer two tuning choices for both the 'Series I' and 'MkII'. One is called the 'Twin Port', which uses--obviously--two small round ports. The other is a 'Big Port' variation which uses a single, very large port. The 'Big Port' offers more mid bass at the expense of some lower bass output. You can use Audio Nirvana 6.5, 8, 10, and 12 inch models with either type of tuning.

Both the '1.3' and the '2.8' can test relatively flat (minus 3 or 4 dB) to 40 cycles and give at least 98 dB from one watt (at one meter). We say 'can' because changing the porting will shift the bass emphasis. We find that some people prefer more output in the 50 to 100 hz range and we developed the 'Big Port' tuning to emphasize this range. 

In response to demand for a smaller monitor type speaker, we completed a design of only 19T x 10.5W x 11.25D, or .87 cubic feet. We call it the 'Minimonitor'. We had our reservations about putting an 8 inch full-range speaker in such a small cabinet, but we were very pleased by the results. The bass rivals any other minimonitor in output and far surpasses them in clarity, detail, accuracy, and realism. All of the astonishing midrange and treble is unchanged by using the smaller cabinet. This speaker could become a reference for all recording studios serious about making great recordings. And it could also become a standard for small speakers in the home environment. It can also be used successfully as a surround speaker or center channel.

Some customers wanted more bass from a 'bookshelf' style speaker than our 'Minimonitor' could provide. For them, we developed the 'Monitor'. Dimensions are 24T x 13.5W x 11.25D. It is 1.5 cubic feet in volume, almost twice the 'Minimonitor's' volume. As such, it produces a lot more bass. The inspiration for this speaker was quality bookshelf speakers from the 1960's and 1970's. This was a golden age for audio. We still don't think mainstream speakers today are as good as they were back then. The 'Monitor' will accept Audio Nirvna 6.5, 8, 10, and even 12 inch models.

Other customers asked for a speaker even smaller than the 'Minimonitor', one that they could use for surrounds, for a center channel, for computer speakers, and as an extension speaker in smaller rooms. For them, we designed the 'Micromonitor'. It's only 16T x 10W x 7.25D, or .41 cubic feet. The 'footprint' is only 10 by 8 inches. The 'Micromonitor' can also be used with a quality subwoofer. With careful matching, we were able to achieve excellent sound. It will accept 6.5 or 8 inch speakers.

Development of our Audio Nirvana 'Super 15 Cast Frame' meant that we needed a new cabinet designed specifically for this speaker. We came up with a beautiful tower speaker of 44T x 18.75W x 14.75D which we call the '5.6'. Such a cabinet produces effortless performance. Big, expansive, powerful. If you have the space, it's an excellent choice. And many customers have also used it for our 10 and 12 inch models, also with excellent results. 

For the 'ultimate', we developed our huge '13.6' cabinet. Dimensions are 48T x 24W x 24D. The 13.6 is capable of producing all the dynamics that anyone could reasonably want in the home environment. It will accept the 'Super 15 Cast Frame' or 'Super 12 Cast Frame.' In addition, it was specially designed to accept two 12 or 15 inch speakers, if the customer chooses. 

While all of our cabinets are satisfying full-range systems in their own right, for those who value extreme dynamics in their listening, or are seeking the lowest possible bass extension (for music or home theater), any of these systems can easily be supplemented with a quality subwoofer. We have done extensive testing of this combination and can tell you, quite honestly, that this will provide all the bass and dynamics you could ever possibly want.

Once you've decided on the bass reflex cabinet that best meets your needs, it is important to note that the material used to make the cabinet is an important factor. Plywoods will generally give a softer sound, particle board--intermediate, MDF will give the most detail. For a soft listening room, you may prefer MDF. Medium rooms--particle board. And for live rooms, we recommend high quality Baltic Birch or marine plywood. As the quality of your source material goes up, so too can the density of the material you use to make your cabinets. 

You can also experiment with different damping materials and how much of it you use inside the cabinet. The main role of the material is to absorb the sound coming from the back of the speaker cone (any speaker cone sends sound to the rear as well as to the front). If this back wave is allowed to reflect off the back of the cabinet and then go forward and strike the cone, it will introduce distortion. Standard procedure is to apply damping material to all sides inside the cabinet except the front baffle. But you can get different--and sometimes better--results by varying how much you use.