affordable sub drivers in europe?

lasercut

Member
Paid Member
2017-12-19 4:35 pm
When searching for drivers instead of active speakers, specifying for ''subwoofers'' doesnt turn up much.
Are there any affordable options (~100euro) for sub-bass drivers in europe currently?
Are there any options aimed at Hifi rather than ''quantity over quality'' bass, and how much do they run?
I dont need high SPL at all, just good extension and decent quality.

To sum up a couple things about it:
- sealed mono sub
- in small but heavily treated 4x5m room
- therefore not loud, quality and extension are a much higher priority
- cross around 100Hz
- will DIY the cabinet
 
Last edited:
Maybe you could define:

- whats your definition of subbass
- how much power is available with your amps
- how loud do you want to go
- what´s your budget?
- Does size of the box matter?
- how are your skills in woodworking? looking for a simple build or is a TL or a tapped horn something you´d like to build?
- to what frequency do you want to go up?
- where in europe are you located?
 

lasercut

Member
Paid Member
2017-12-19 4:35 pm
To sum up a couple things about it:
- sealed mono sub
- in small but heavily treated 4x5m room
- therefore not loud, quality and extension are a much higher priority
- cross around 100Hz
- will DIY the cabinet

The only thing im caught up on is choosing a driver,
Is SPL the main reason to go for a huge 18'' driver? frequency response looks roughly the same for most woofers regardless of size.
 

kipman725

Member
Paid Member
2007-06-10 12:41 pm
Warrington
The cone will move less to generate your desired SPL which normally means lower distortion for the larger driver even if its full capability isn't used. I use 15" drivers in tall but small footprint cabs to fit my room corners.

here is a thread full of peoples opinions on Hi-Fi woofers Vs PA woofers:
Are 18", 21" pro audio subwoofers better than 12", 15" hifi subwoofers?

I found the best improvement to perception of bass at home was to use four subwoofers and room equalization. A single sub has massive variation in response depending on position.
 

kipman725

Member
Paid Member
2007-06-10 12:41 pm
Warrington
ok, thanks for the link there is some useful info in there.
for example the big pro woofers are designed for ported enclosure so might end up with early roll off since im going sealed.

For sealed you should look at total air volume displacement capability of the system, this is constrained by:
Cone area
Maximum linear excursion
Amplifier output voltage capability

All sub systems need EQ so I wouldn't focus on flat response. The drivers that will give the most displacement in sealed system for a given cone diameter are usually targeted at home theater or car audio. However the problem with car audio drivers is that the specs (if given) are quite often garbage. I have been using large quantities of Pyle PLPW15D but beyond been cheap and having decent xmax they don't have any positive qualities.
 

lasercut

Member
Paid Member
2017-12-19 4:35 pm
I want to avoid any EQ, using a larger sealed box to get low Q.
The sub will have its own amp so gain can be adjusted at least.
This will be the first attempt, with things kept simple. EQ or porting can come later depending on results

The Scan Speak woofer waxx posted above piqued my interest, it has very low Fs of 23Hz for this price range.
It is a bit limited in xmax so may not be suited for this kind of application.
However it lead me to the SB29NRX75,
similar specs, more expensive, but has 11mm linear xmax compared 6mm linear xmax of the Scan Speak.
The Scan speak gives a max mechanical excursion of 12mm, but the SB woofer doesnt give this spec... maybe im being mislead and the SB linear xmax is actually max mechanical excursion. 50W better power handling would hint that it is the true xmax spec.

also paper cones which matches my main speaker.
 
Last edited:
The Scan Speak woofer waxx posted above piqued my interest, it has very low Fs of 23Hz for this price range.
It is a bit limited in xmax so may not be suited for this kind of application.
However it lead me to the SB29NRX75,
similar specs, more expensive, but has 11mm linear xmax compared 6mm linear xmax of the Scan Speak.
The Scan speak gives a max mechanical excursion of 12mm, but the SB woofer doesnt give this spec... maybe im being mislead and the SB linear xmax is actually max mechanical excursion. 50W better power handling would hint that it is the true xmax spec.

also paper cones which matches my main speaker.

The SB29NRX75-6 has a lower qts (0.35 vs 0.40), wich makes it less ideal for a closed system as the FS will probally be higher but the speaker will take more watt before going in overexcursion, that is true.

But in my experience, my woofer takes 50 watt before i loose sub (in a big vented box tuned to 25Hz), so i don't know if that will be a big issue for you...
 

kipman725

Member
Paid Member
2007-06-10 12:41 pm
Warrington
I want to avoid any EQ, using a larger sealed box to get low Q.
The sub will have its own amp so gain can be adjusted at least.
This will be the first attempt, with things kept simple. EQ or porting can come later depending on results

The Scan Speak woofer waxx posted above piqued my interest, it has very low Fs of 23Hz for this price range.
It is a bit limited in xmax so may not be suited for this kind of application.
However it lead me to the SB29NRX75,
similar specs, more expensive, but has 11mm linear xmax compared 6mm linear xmax of the Scan Speak.
The Scan speak gives a max mechanical excursion of 12mm, but the SB woofer doesnt give this spec... maybe im being mislead and the SB linear xmax is actually max mechanical excursion. 50W better power handling would hint that it is the true xmax spec.

also paper cones which matches my main speaker.

SB29NRX75 lists an air gap height of 6mm and a voice coil height of 28mm. therfore the voice coil has an overhang of 11mm (traditional measurement of xmax and the same as the 22mm pp linear coil travel number). This is xmax because once the cone moves beyond this point not all the coil is in the air gap where the magnetic field is concentrated.

Most pro drivers also add 1/4 to 1/3rd of the air gap height to this number to take into account fringing fields. So this driver could be rated up to 13 mm xmax. However even if the motor of a driver maintains BL suspension/surround non linearity can limit acceptable distortion at high excursion; to this end B&C have an xvar measurement that gives the maximum excursion before non linearity, usually this is greater than xmax because of the before mentioned fringing fields. For super high excursion drivers (xmax>15mm) its quite likely that suspension or surround non linearity limits output before xmax.

Incidentally the coil mostly not been in the magnetic gap gives the SB29NRX75 a BL^2/RE of only 27.3 whereas many pro drivers exceed 200. If you read the papers in the before mentioned forum thread you can see that this results in a larger subwoofer required for a given output SPL.
 
Last edited:
Is there any rough example you can give for how loud it is at 50W?

Theoretical it should be 111dB for a pair, but you need to take at least 3dB off because of the passive CR i use, and ad 3-10dB roomgain (depending on the room) if you use it inside.

In any case it's louder than 102dB, what is the industry norm, and way more than i ever use. I use it now with an 32w Prima Luna Prologue 4 tube amp that also feeds the Mark Audio 10M Gen 3 tops trough a passive CR and half open is already ridicous loud in my living rooom (8x6x2.5m). With the amp full open and bass heavy music (like dub) playing, the windows start to rumble and my neighbours complaining and calling the police... :D

But most of the time, i listen on a 60 till 90dB level.

I did use them also in an active 2 way with an Minidsp and powered with an Marantz PM5004, and also with a 50w custom transistor AB class amp for small home parties (25ppl) and they did an exelent job then.
 
Last edited:

lasercut

Member
Paid Member
2017-12-19 4:35 pm
Thanks for explaining the xmax spec, makes sense.

Sounds like the ScanSpeak should be ok.
Im crossing with an alpair 7p low enough to get away with mono.
Aside from cost, there are so many reasons to go stereo over mono that ill probably end up getting another, at which point there would be no need for SB29NRX75 greater xmax