Firstly hi all!
I'm trying to build a pair of speakers as a base for my living room audio system, the components I have been collecting. I have 2x Bowers and Wilkins signature 800 bass drivers, 2x b&w 8nt bass drivers 4x b&w Kevlar signature 800 series midrange drivers,
My plan is to buy 4 decent tweeters to go with these and build 2 speakers using the sig 800 bass drivers and another 2 using the 8 nt bass drivers,
I'm struggling with what tweeters to go for.... I guess the obvious choice would be b&w ones... But I'd welcome any suggestions.
Enclosure dimensions and bracing design I am going to copy/scale down from the original sig 800 series measurements...
The issue I have is the crossovers for the sig 800 drivers, the spec sheet for 800s says they use a 350hz 4khz crossover, I have been looking on ebay etc to see if I can find any aftermarket or similar crossovers within this range... But I'm struggling
I can solder so could make some, but I just don't know where to start with designing a circuit or what components to use I see the original 800's use mcap capacitors... Are there any decent similar makes I could use?
I'm really new to all this, so any guidance or recommendations on design or tweeter choice really would be appreciated
I'm trying to build a pair of speakers as a base for my living room audio system, the components I have been collecting. I have 2x Bowers and Wilkins signature 800 bass drivers, 2x b&w 8nt bass drivers 4x b&w Kevlar signature 800 series midrange drivers,
My plan is to buy 4 decent tweeters to go with these and build 2 speakers using the sig 800 bass drivers and another 2 using the 8 nt bass drivers,
I'm struggling with what tweeters to go for.... I guess the obvious choice would be b&w ones... But I'd welcome any suggestions.
Enclosure dimensions and bracing design I am going to copy/scale down from the original sig 800 series measurements...
The issue I have is the crossovers for the sig 800 drivers, the spec sheet for 800s says they use a 350hz 4khz crossover, I have been looking on ebay etc to see if I can find any aftermarket or similar crossovers within this range... But I'm struggling
I can solder so could make some, but I just don't know where to start with designing a circuit or what components to use I see the original 800's use mcap capacitors... Are there any decent similar makes I could use?
I'm really new to all this, so any guidance or recommendations on design or tweeter choice really would be appreciated
I have been reading the 'sticky' on crossover design but its still too technical for me, are there any 'generic' crossovers available that would sound ok that are recommended? I know that it's probably not the best solution to get the best out of these components but its probably my best option du to my limited technical knowledge? Are there any Adjustable 3 way crossovers out there?? That you can 'tune' once installed?
"The issue I have is the crossovers for the sig 800 drivers, the spec sheet for 800s says they use a 350hz 4khz crossover, I have been looking on ebay etc to see if I can find any aftermarket or similar crossovers within this range... But I'm struggling"
Eminence make a very nice 3way xover.
eminence crossover | eBay
Or take a look at CPC - Over 100, 000 products from one of the worlds leading distributors of electronic and related products. | CPC
Check to see which has the best price, ebay is retail!
Eminence make a very nice 3way xover.
eminence crossover | eBay
Or take a look at CPC - Over 100, 000 products from one of the worlds leading distributors of electronic and related products. | CPC
Check to see which has the best price, ebay is retail!
Thanks loads for your reply Jon! I had a look at some eminence ones on ebay, and also these
Pro Audio Crossover 3 Way 400hz/3.5khz - British Built - Highest Quality! (Pair) | eBay
would you have any recommendations on a good pair of tweeters?
Thanks
Pro Audio Crossover 3 Way 400hz/3.5khz - British Built - Highest Quality! (Pair) | eBay
would you have any recommendations on a good pair of tweeters?
Thanks
Bowers, you ought to be aware that B&W generously supply crossover schematics on their website:
B&W Group North America Service & Support - Service Manuals
You should find the speakers that use your bass and mid drivers, and hopefully a lot of the work is done for you. Using Windows snipping tool to get the schematics in a compact form and post them here.
It's not hard to then work out a suitable standard tweeter and filter and alignment to match. Well, I don't find it hard! 😱
http://www.visaton.com/en/chassis_zubehoer/ht_kalotten/index.html
http://www.seas.no/index.php?option=com_content&view=article&id=43&Itemid=48
A good filter is easily tweaked for level. 😎
B&W Group North America Service & Support - Service Manuals
You should find the speakers that use your bass and mid drivers, and hopefully a lot of the work is done for you. Using Windows snipping tool to get the schematics in a compact form and post them here.
It's not hard to then work out a suitable standard tweeter and filter and alignment to match. Well, I don't find it hard! 😱
http://www.visaton.com/en/chassis_zubehoer/ht_kalotten/index.html
http://www.seas.no/index.php?option=com_content&view=article&id=43&Itemid=48
A good filter is easily tweaked for level. 😎
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At 4kHz crossover you could look at using a ribbon tweeter like Fountek Neo1CD Fountek NeoCD1.0 Ribbon Tweeter 296-701.
My two cents....if you can get the xo design and corresponding drivers, I'd piece together a B&W.
Three-ways are tough to get right.
Three-ways are tough to get right.
right!.... thanks all for the advice..I think im going to go for it System7 and build some B&W "Copy" Crossovers using the specs for the d800's on the link you provided!... my shopping list consists of the following
Sub LF Crossover:
2 x 100uf 400vdc polypropylene Capacitor
1 x 2.5mH 1.8mm wire air core Inductor
1 x 2.5mH 1.0mm wire air core Inductor
2 x OR5 or 1R or 1R5 100W RNP50S
MID MF Crossover:
2 x 22uf 800vdc polypropylene Capacitor
1 x 10uf 1200vdc polypropylene Capacitor
1 x 1.15mH 1.2mm wire air core Inductor
1 x 0.7mH 1.2mm wire air core Inductor
1 x 2R or 2R5 or 3R 100W RNP50S
HIGH HF Crossover:
1 x 4uf 1200vdc polypropylene Capacitor
1 x OR5 or 1R or 1R5 100W RNP50S
im going to try and source the correct B&W tweeters for this model but if I went for a reed type could I use the same crossover on it??...
also any things to bare in mind when buying the above components?? are there any recommended makes?.. or any recommended uk supplyers?
thanks again everyone!!!!! you have been more than helpful!
Sub LF Crossover:
2 x 100uf 400vdc polypropylene Capacitor
1 x 2.5mH 1.8mm wire air core Inductor
1 x 2.5mH 1.0mm wire air core Inductor
2 x OR5 or 1R or 1R5 100W RNP50S
MID MF Crossover:
2 x 22uf 800vdc polypropylene Capacitor
1 x 10uf 1200vdc polypropylene Capacitor
1 x 1.15mH 1.2mm wire air core Inductor
1 x 0.7mH 1.2mm wire air core Inductor
1 x 2R or 2R5 or 3R 100W RNP50S
HIGH HF Crossover:
1 x 4uf 1200vdc polypropylene Capacitor
1 x OR5 or 1R or 1R5 100W RNP50S
im going to try and source the correct B&W tweeters for this model but if I went for a reed type could I use the same crossover on it??...
also any things to bare in mind when buying the above components?? are there any recommended makes?.. or any recommended uk supplyers?
thanks again everyone!!!!! you have been more than helpful!
Keep in mind that the crossover components are dictated by drivers, acoustic target slopes, baffle/box geometry and crossover frequency.
So if you use bass and mid drivers of the 800D AND use the same box (at least the same baffle) you can use the same 800D crossover but only for the bass-mid integration i.e. low pass for the bass and high pass for the mid. Not the low pass for the mid unless you'll use the same tweeter. If you change the tweeter you'll have to redesign the low pass for the mid and high pass for the tweeter. Also notice that the tweeter part consist of only one cap, few tweeter can tolerate a 1st order electrical crossover at mid to high SPL.
So in the end don't buy the exact 800D components for the mid and tweeter integration if you're not planning to use the 800D tweeter.
Ralf
So if you use bass and mid drivers of the 800D AND use the same box (at least the same baffle) you can use the same 800D crossover but only for the bass-mid integration i.e. low pass for the bass and high pass for the mid. Not the low pass for the mid unless you'll use the same tweeter. If you change the tweeter you'll have to redesign the low pass for the mid and high pass for the tweeter. Also notice that the tweeter part consist of only one cap, few tweeter can tolerate a 1st order electrical crossover at mid to high SPL.
So in the end don't buy the exact 800D components for the mid and tweeter integration if you're not planning to use the 800D tweeter.
Ralf
Thanks giralfino I'll keep that in mind..... I have spent most of the day trying to track down the components on my list and can't seem to find any at the right voltages..... The caps in my list seem massive the only ones I could find other than mcap ones are motor starter caps... Anyone used these ??? 🙂 I'm on a super low budget build
Bowers, I find no evidence that the D800 even exists! 😕
I DO find an 800D.
http://www.bwgroupsupport.com/manuals/bw-service
It's up to you to match the Bass and Mid drivers to an existing design. We can sort out the substitute tweeter type and crossover later. Don't worry about the capacitor types and voltages or the exact coil specs at this stage. We just need a target speaker to replicate. I am not in the exotic component camp myself. Cheap and cheerful does it every time for me.
Trust the experienced forum members to iron out the details. But I for one don't have the time to do the homework for you. It's your baby. 😀
Hmm I'm not sure I understand, your right the mids and subs I have are from the 800D's not D800, I thought that all I needed to do was buy components of the same values as the original spec crossovers and then copy the design although I will only be using one bass driver in each enclosure as apposed to 2 in each enclosure as per the origional 800D B&Ws... I'm a complete novice ( I'm sure that's apparent 🙂 ) what's the normal formular for working out what crossovers I need? I understand that the capacitor voltages are the maximum that I want it to be able to charge to? But in reality these can be much lower? Can I use ones with the same rating but a lower voltage? Also with the inductors can I use ones of the same rating but a slightly different guage wire?... Sorry if I'm way off the mark but I really have no experience of electronics design... Is it better to forget the original xo design and just design/calculate the xo design based on the driver spec?
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So you are building a different speaker. The crossover won't work correctly with only one bass for two reasons: the impedance is wrong (double than the intended one), and the SPL is lower (more or less 6dB). If I were in your boots I would sell the 2 wrong bass drivers and 2 midranges, buy 2 correct bass and tweeters and build only one pair of 800D clones, using the supplied crossover.
As for the crossover components, the ones depicted in the B&W manual are of the exotic type and expensive (on the other hand the 800D IS expensive). You can use lower price parts, like Jantzen Cross Cap or Intertechnik KP-QS both 400V for the caps. For inductors, I would try to find ones with the exact gauge, because else you'll change the crossover behavior. The 1.2mm ones are not expensive, the 2.5mH 1.8mm ones are a bit pricey, the minimum I would go are 1.6mm, or I would try to match the inductance/resistance with a cored coil: for example a 2.5mH 1.8mm air core coil has a resistance of about 0,35 Ohm, the same can be achieved with a cored coil with a 1mm wire (check before buy).
BTW, I spotted 2 errors in your list: the tweeter cap is 4.7uF (not 4uF), and the bass coils are 2.5mH and 1.0mH both 1.8mm. I would also check with B&W why there are some choices for coils (1.0 or 1.6, 1.15 or 1.25, 0.7 or 0.8).
You cannot calculate a crossover based on specs, you need frequency response and impedance measurements.
Ralf
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are you going to build exactly the same cabinet as the originals?
pre determined xo is pretty much useless. the right passive xo will need a complete data kf impedance of each drivers, and to shape it correctly you will need to measure the freq response with your BOX in order to have correct transfer function.
if you dont do the same box and the same drivers (configuration, position and qty) you will need to have some basic measurement equipment.
dats and omnimic is minimum for it.
before you build the cabinets, you will need to design the box for the woofer and midrange, in order to predict the bass response and possible transfer function between the bass and midrange.
cheers
henry
pre determined xo is pretty much useless. the right passive xo will need a complete data kf impedance of each drivers, and to shape it correctly you will need to measure the freq response with your BOX in order to have correct transfer function.
if you dont do the same box and the same drivers (configuration, position and qty) you will need to have some basic measurement equipment.
dats and omnimic is minimum for it.
before you build the cabinets, you will need to design the box for the woofer and midrange, in order to predict the bass response and possible transfer function between the bass and midrange.
cheers
henry
Bowers,
PM'd you, but for me the may considerations would be:
- You seem to have a bizarre miss-match of drivers? (4 mid drivers and 2 bass from 800 series?)
- If you have a matching set of drivers, or can easily order a few tweeters to achieve a set, then I'd recommend building strictly to the original B&W design. Loss in cabinet volume is a loss in bass response.
- Once you've built a 'clone' speaker I'd recommend you try a lower value inductor on the mid driver, it may well change the sound more to yout liking- this comes more under 'voicing' than anything else.
I've PM'd you my details.
PM'd you, but for me the may considerations would be:
- You seem to have a bizarre miss-match of drivers? (4 mid drivers and 2 bass from 800 series?)
- If you have a matching set of drivers, or can easily order a few tweeters to achieve a set, then I'd recommend building strictly to the original B&W design. Loss in cabinet volume is a loss in bass response.
- Once you've built a 'clone' speaker I'd recommend you try a lower value inductor on the mid driver, it may well change the sound more to yout liking- this comes more under 'voicing' than anything else.
I've PM'd you my details.
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