DIY subwoofers, Help

[nikodem]

Hello friends,

Music gives me life. I consume a lot of it. I have a simple setup that i am moderately satisfied with. This is not for a home theatre but simply listen to music.

I have a pair of Bowers & Wilkins CM6 S2. I love the clean, rich, punchy sound they produce but do lack some depth in the bass. This is why i have chosen to DIY build two subs to match my needs.

Im looking to build two reasonably high-end sealed subs. Something that helps me in the low frequencies but even more so gives me a rapid, punchy and tight bass. Ive been reading a lot and it seems to only make me feel dumber than I was before.

As for a driver i've looked at the Monacor SPH 225 C. An 8", 120W Rms, 8ohm driver. Not sure this will match my needs. Just feels that if maxed it will produce a punchy bass?
I understood it is easier to use an external amp. Not sure what to look for, can one amp drive both subs?
For the cabinet. My friend is a master cabinet maker and will help with this as long as i provide instructions.

I want to build the most high end pair of subs for my need with a budget of around 1200$. Im all up for buying used gear too.

What do you think?
Would I need bigger drivers?
What kind of amps would you recommend?
I really appreciate all the help and I hope I’m in the right place.
THANK YOU!!

/Nikodem from Sweden.

 

[lovinthehd]

I like DIY subs, do that myself. Whether they'll make up for the B&W speakers could be another conversation.

I would think about larger drivers, 8" is particularly limited for subs. Somewhat depends what your extension and spl goals are, tho (how low does it need to and at what spl level?). Using one amp for two diy subs generally offers good economics (but generally your time is going to have to be "free" ). You are using some good software to model with? Maybe try winisd or bass box pro or others. Figure out the driver/box needed for your goals then the amp needs will be dictated for the most part. Generally I'd go external amps either dedicated power amps or pro style amps generally, but depends on your design and dsp needed (sealed designs particularly would need some dsp to bring up the lower end).

 

[nikodem]

I like DIY subs, do that myself. Whether they'll make up for the B&W speakers could be another conversation.

Hey,

Hahaha, i knew that would come up. The B&W. I bought them years ago, will probably upgrade soon.

Thank you so much for such a quick answer!! The only reason it took me so long to answer is because i needed to learn what SPL means and more. Hehe.

Yeah, i was thinking that 8" might be too small. 10-12 might be better. Im not looking to build a beast of a system, just adding some more depth. Honestly, i have no idea what SPL i want. Ive understood something around/above the 90 range is good. So i guess around that region. I will primarily be using it in a room that is about 23 sqm /250 square feet.

Sadly winisd doesnt work on Mac. Ill run something on my brothers PC tomorrow. Just not sure what values to input. I could definetly go for two amps.

I looked at these two drivers MONACOR SPH-250CTC & MONACOR SPH-300CTC (see pic). Both seem to have twin coils. Not sure if that requires more/stronger amps? The specs look good for my novice eyes.

Thank you!!!!!

 

[lovinthehd]

Twin coils offer usually just some different wiring setups for impedance load, and your impedance requirements can definitely affect amp choice. Macs are indeed limited....

 

[TLS Guy]

Hello friends,

Music gives me life. I consume a lot of it. I have a simple setup that i am moderately satisfied with. This is not for a home theatre but simply listen to music.

I have a pair of Bowers & Wilkins CM6 S2. I love the clean, rich, punchy sound they produce but do lack some depth in the bass. This is why i have chosen to DIY build two subs to match my needs.

Im looking to build two reasonably high-end sealed subs. Something that helps me in the low frequencies but even more so gives me a rapid, punchy and tight bass. Ive been reading a lot and it seems to only make me feel dumber than I was before.

As for a driver i've looked at the Monacor SPH 225 C. An 8", 120W Rms, 8ohm driver. Not sure this will match my needs. Just feels that if maxed it will produce a punchy bass?
I understood it is easier to use an external amp. Not sure what to look for, can one amp drive both subs?
For the cabinet. My friend is a master cabinet maker and will help with this as long as i provide instructions.

I want to build the most high end pair of subs for my need with a budget of around 1200$. Im all up for buying used gear too.

What do you think?
Would I need bigger drivers?
What kind of amps would you recommend?
I really appreciate all the help and I hope I’m in the right place.
THANK YOU!!

/Nikodem from Sweden.

Those are high sensitivity very low Qts drivers. They will play loud, but not low, and are totally unsuitable for a sealed cabinet.
They are basically instrument speakers for a large venue.

I would counsel you against building sealed subs. Sealed subs requite expensive drivers, with large excursion. Also the f3 without equalization is usually an octave or so above fs. So that means an expensive motor system and equalization at 12 db/octave boost below f3. So that adds complication and takes a lot of amplifier power. That is not a project for a beginner.

A good ported design is the best approach for a beginner. That will have a far lower budget and lead to much better results if properly designed.

So what drivers do you have available in Sweden? I would guess that Scandinavian built drivers are the easiest to obtain, and some are excellent sub drivers.

 

[nikodem]

Those are high sensitivity very low Qts drivers. They will play loud, but not low, and are totally unsuitable for a sealed cabinet.

Hey,

Thank you so much for the pedagogical approach. I see that now!

I think i wanted sealed to keep the size to a minimum, also because it feels better. But if you advise against it ill take your advice.

In regards to drivers, i'm not foreign to ordering them from anywhere, especially in europe. Right now i've been looking at a site in Germany, Poland and Sweden. Would love to find used hardware.

Best, Nikodem

 

[TLS Guy]

Hey,

Thank you so much for the pedagogical approach. I see that now!

I think i wanted sealed to keep the size to a minimum, also because it feels better. But if you advise against it ill take your advice.

In regards to drivers, i'm not foreign to ordering them from anywhere, especially in europe. Right now i've been looking at a site in Germany, Poland and Sweden. Would love to find used hardware.

Best, Nikodem

I'm in the US, you are apparently in Sweden, so you need to link vendor sites you have access to, so I can help you. I don't want a time wasting exercise.
Successful speaker design involves a lot of steps. The crucial first step is driver selection. If you are going to put someone else's cast off driver, I'm not going to help you with that.
One of the things that is essential is having reliable data on the Thiel/Small parameters of drivers under consideration. The physics has to line up correctly, or the sub will not work. Every detail being right is essential.

 

[nikodem]

I'm in the US, you are apparently in Sweden, so you need to link vendor sites you have access to, so I can help you. I don't want a time wasting exercise.
Successful speaker design involves a lot of steps. The crucial first step is driver selection. If you are going to put someone else's cast off driver, I'm not going to help you with that.
One of the things that is essential is having reliable data on the Thiel/Small parameters of drivers under consideration. The physics has to line up correctly, or the sub will not work. Every detail being right is essential.

Hey, i got it!

Did the links not work? I liked to these sites:

Woofer | hifisound.de | Your online hifi specialist

Speaker Drivers - Woofer. hifisound.de

www.hifisound.de

Głośniki niskotonowe (Woofer)

Głośnik niskotonowy Kompaktowe kształty, które wyznaczają głośniki niskotonowe, wpływają zarówno na walory estetyczne każdego tego typu przestrzeni domowej, jak i jej praktyczność. W nowoczesnych salonach przeważa raczej chęć ukrywania

www.poweraudio.pl

Thomann Köp förmånligt prissatta Högtalare 12’’ online på Thomann

Köp Högtalare 12’’ + tillbehör online hos Europas största musikåterförsäljare - Snabb leverans, 30 dagars öppet köp och 3 års Thomann-garanti

www.thomann.de

Best,
Nikodem

 

[TLS Guy]

Hey, i got it!

Did the links not work? I liked to these sites:

Woofer | hifisound.de | Your online hifi specialist

Speaker Drivers - Woofer. hifisound.de

www.hifisound.de

Głośniki niskotonowe (Woofer)

Głośnik niskotonowy Kompaktowe kształty, które wyznaczają głośniki niskotonowe, wpływają zarówno na walory estetyczne każdego tego typu przestrzeni domowej, jak i jej praktyczność. W nowoczesnych salonach przeważa raczej chęć ukrywania

www.poweraudio.pl

Thomann Köp förmånligt prissatta Högtalare 12’’ online på Thomann

Köp Högtalare 12’’ + tillbehör online hos Europas största musikåterförsäljare - Snabb leverans, 30 dagars öppet köp och 3 års Thomann-garanti

www.thomann.de

Best,
Nikodem

There were no links in your previous post.

Unfortunately you have a very poor selection of subwoofer drivers, and the vendors do not seem to know the difference between a woofer, and a subwoofer driver.

Anyhow this Peerless is a sub driver and it good value for money.

I sense you are on a budget. I think I can design you a very acceptable sub using the above driver. If that driver and price are acceptable to you, I can design you a very respectable sub I think, if that is what you would like.

 

[nikodem]

There were no links in your previous post.

Unfortunately you have a very poor selection of subwoofer drivers, and the vendors do not seem to know the difference between a woofer, and a subwoofer driver.

Anyhow this Peerless is a sub driver and it good value for money.

I sense you are on a budget. I think I can design you a very acceptable sub using the above driver. If that driver and price are acceptable to you, I can design you a very respectable sub I think, if that is what you would like.

I am so thankful for your help!!

I mean, i have about 1000 USD to spend on drivers and amps. So yeah, i guess a bit tight if i want to build two. If you think those drivers will do it i trust you. I would love to know how you're thinking. Within what ranges should i stay to get that tight punchy bass? Im thinking ill play around in WINISD.

Best,

Nikodem

 

[TLS Guy]

I am so thankful for your help!!

I mean, i have about 1000 USD to spend on drivers and amps. So yeah, i guess a bit tight if i want to build two. If you think those drivers will do it i trust you. I would love to know how you're thinking. Within what ranges should i stay to get that tight punchy bass? Im thinking ill play around in WINISD.

Best,

Nikodem

The punch, is very much in the design. To some extent the driver, at least the selection. expense of the driver is related to power handling and cine excursion more than anything else.

I'm busy today, but I will do you a design tomorrow and send you a pdf. of it. You can model subs very accurately.

I think you will come close to budget for two of those subs, at least for divers and an amp. I would use a two channel power amp and not a plate amp. I will do a ported design, so you won't have to worry about Eq.

 

[TLS Guy]

I am so thankful for your help!!

I mean, i have about 1000 USD to spend on drivers and amps. So yeah, i guess a bit tight if i want to build two. If you think those drivers will do it i trust you. I would love to know how you're thinking. Within what ranges should i stay to get that tight punchy bass? Im thinking ill play around in WINISD.

Best,

Nikodem

Here is your design. This makes a very nice cost effective sub as I suspected. One or two of these will meet your needs perfectly.

You must add, the driver volume displacement, bracing and port volume to the total internal volume. I estimate this will be about another 0.2 to 0.25 cu.ft.

The port is flared at the baffle end. You should cover half the internal volume with polyfill.

You could use a couple of plate amps, but I would use a two channel amp of 100 to 150 watts per channel if you can afford it. Two plate amps though would be cheaper. What you could get similar to this in Sweden would do the job. With plate amps, I would get something a little more powerful than you need for reliability reasons, then they won't be stressed. So something 150 to 250 watts.

If you build one or two of these you will not be disappointed.

 

[TLS Guy]

Here is your design. This makes a very nice cost effective sub as I suspected. One or two of these will meet your needs perfectly.

You must add, the driver volume displacement, bracing and port volume to the total internal volume. I estimate this will be about another 0.2 to 0.25 cu.ft.

The port is flared at the baffle end. You should cover half the internal volume with polyfill.

You could use a couple of plate amps, but I would use a two channel amp of 100 to 150 watts per channel if you can afford it. Two plate amps though would be cheaper. What you could get similar to this in Sweden would do the job. With plate amps, I would get something a little more powerful than you need for reliability reasons, then they won't be stressed. So something 150 to 250 watts.

If you build one or two of these you will not be disappointed.

I see goods are really high in price in Sweden compared to US.

So the 100 watt Dayton plate amps are just under $400.00 USD each and the drivers around $300.00 each. So if you build two subs it will cost you $1400 USD in drivers and amps. This outfit has the driver for 220 Euro each which is $250 USD each. So that would get your cost down to $1300.00 USD.

This outfit in Holland has the Dayton 250 watt plate amp for 220 Euro, which is $250 USD. So now we are at $1000.00 USD D for the pair. That is progress!