Reckhorn B2
Nov 19, 2009 16:15:39 GMT -7
Post by jagman on Nov 19, 2009 16:15:39 GMT -7
Hey guys. I've been interested in getting a simple bass management device for my IB sub that includes a SSF. Like most of you, I use a pro amp to power my subwoofer. Like many of you, I've often wondered if my amp was receiving a powerful enough signal from the sub out from my receiver to function at it's best. Reckhorn has a product called the B2 that could fill my needs. If interested, check out a PDF of the Users Manual. As you can see in the links, the B2 has a user adjustable 4th order SSF that can theoretically be set as low as 10Hz. It also has a user adjustable one octive parametric EQ filter that can boost the signal at the chosen frequency up to 12 dB. Lastly, it has gain control. Since most devices with gain control are unity gain (that is they only cut gain), I had hopes that this device would be different.
So... I contacted Reckhorn regarding their B2 device via e-mail, and this was the exchange...
So... the B2 has:
1. A user adjustable SSF that can go as low as 10Hz
2. A user adjustable one band, one octive parametric EQ filter that can boost the signal up to 12dB
3. A gain adjustment knob that can decrease gain, but also increase it up to 10v
A person on another forum I frequent also has a B2 that he uses and has found that the SSF when set to 10Hz actually performs like it is set to 12Hz. That tells me this device has a lot of potential, but is not as accurate as it could be. To get around this, all one has to do is to run closed curcuit sweeps with REW to see what the various adjustments really do. Considering what we already do with REW when setting up our BFDs, that should be pretty simple. Then we modify our SSF and low frequency boost settings based on what WinISD recommends for our subwoofers given how many watts we send each drivers.
Based on my needs and what I've heard so far, I went ahead and ordered a B2 for my HT. It will take a while to get it set up (I recently moved), but I'll report back once my HT is properly installed.
A couple other thoughts...
1. Obviously 1 band of EQ is less than most people on this forum use when dialing in his IB sub... but I don't see why a BFD couldn't also be used in the chain. Since most of us already have a BFD, that shouldn't be an issue.
2. Many people use sophisticated automated room EQ systems (like Audyssey) for their HT. The main complaint I've heard is that these systems automatically go to a flat response over a relatively large area (multiple seats). If one wanted, he could get the B2 and set the gain and SSF appropriately for his sub amp and drivers. Then, while keeping the boost EQ at 0dB, run the auto EQ. Afterwards, he could set the one octive parametric EQ to 20Hz and dial in boost. Since the auto EQ is set to give a flat response to a large area, the one band parametric EQ house curve should in theory extend to a larger area than just the sweet spot. This way, one can safely drive his subwoofer, use modern auto EQs, yet not lose the ability to have a house curve. Of course this is theory, but I plan to test it out and see how things sound.
So... I contacted Reckhorn regarding their B2 device via e-mail, and this was the exchange...
I live in America and purchased the B2 Bass Management device yesterday through Bob Reimer at CSS in Canada. I have one question regarding it's gain conrol. Does the B2 have + and - gain control or is it just an attenuator?
The MAIN LEVEL is the gain control. At 12:00 o'clock = straight up the gain is about 0 dB: input = output signal. From 12:00 - 17:00 you can increase output signal up to 10 volts.
The MAIN LEVEL is the gain control. At 12:00 o'clock = straight up the gain is about 0 dB: input = output signal. From 12:00 - 17:00 you can increase output signal up to 10 volts.
I have an infinite baffle subwoofer and am looking forward to protecting the drivers from the really low frequencies... not to mention using the parametric boost at 20Hz. Having + and - gain control would be really nice since the subwoofer is powered by a pro amp but I'm using a consumer A/V receiver.
Yes, this exactly is the purpose of B-2. Many users buy it for the variable SUBSONIC only. Every subwoofer will sound better when you filter iddle / blind power = what your amp produces but your speaker cannnot deliver. Very important for bass reflex as well: below the port tuning frequency the response curves goes down sharply - but the amp is still pumping lower frequency power into the speaker voice coil which heats up resulting in thermal compresion (higher impedance of hot coils) and eventually burning. Many use it for smaller speakers like 3-5" full range. These speakers are good for one point source but the X-max. is short = very limited bass capability. If you set the SUBCSONIC just as high as you hear slightly less bass than this is the right setting where the speaker is limited and should be relaxed from those iddle power. This will also keep yur amp cooler or you have more reserve to have more power reserve for the audible range. Do not underestimate the variable / parametric BOOST LEVEL. You can extend bass about 1/2 octave. The trick is a well set combination with SUBSONIC. .
Yes, this exactly is the purpose of B-2. Many users buy it for the variable SUBSONIC only. Every subwoofer will sound better when you filter iddle / blind power = what your amp produces but your speaker cannnot deliver. Very important for bass reflex as well: below the port tuning frequency the response curves goes down sharply - but the amp is still pumping lower frequency power into the speaker voice coil which heats up resulting in thermal compresion (higher impedance of hot coils) and eventually burning. Many use it for smaller speakers like 3-5" full range. These speakers are good for one point source but the X-max. is short = very limited bass capability. If you set the SUBCSONIC just as high as you hear slightly less bass than this is the right setting where the speaker is limited and should be relaxed from those iddle power. This will also keep yur amp cooler or you have more reserve to have more power reserve for the audible range. Do not underestimate the variable / parametric BOOST LEVEL. You can extend bass about 1/2 octave. The trick is a well set combination with SUBSONIC. .
So... the B2 has:
1. A user adjustable SSF that can go as low as 10Hz
2. A user adjustable one band, one octive parametric EQ filter that can boost the signal up to 12dB
3. A gain adjustment knob that can decrease gain, but also increase it up to 10v
A person on another forum I frequent also has a B2 that he uses and has found that the SSF when set to 10Hz actually performs like it is set to 12Hz. That tells me this device has a lot of potential, but is not as accurate as it could be. To get around this, all one has to do is to run closed curcuit sweeps with REW to see what the various adjustments really do. Considering what we already do with REW when setting up our BFDs, that should be pretty simple. Then we modify our SSF and low frequency boost settings based on what WinISD recommends for our subwoofers given how many watts we send each drivers.
Based on my needs and what I've heard so far, I went ahead and ordered a B2 for my HT. It will take a while to get it set up (I recently moved), but I'll report back once my HT is properly installed.
A couple other thoughts...
1. Obviously 1 band of EQ is less than most people on this forum use when dialing in his IB sub... but I don't see why a BFD couldn't also be used in the chain. Since most of us already have a BFD, that shouldn't be an issue.
2. Many people use sophisticated automated room EQ systems (like Audyssey) for their HT. The main complaint I've heard is that these systems automatically go to a flat response over a relatively large area (multiple seats). If one wanted, he could get the B2 and set the gain and SSF appropriately for his sub amp and drivers. Then, while keeping the boost EQ at 0dB, run the auto EQ. Afterwards, he could set the one octive parametric EQ to 20Hz and dial in boost. Since the auto EQ is set to give a flat response to a large area, the one band parametric EQ house curve should in theory extend to a larger area than just the sweet spot. This way, one can safely drive his subwoofer, use modern auto EQs, yet not lose the ability to have a house curve. Of course this is theory, but I plan to test it out and see how things sound.
