Hello
Last mount I bought 4 Reckhorn D165 drivers and I'd like to build four sealed subwoofers.
https://reckhorn.com/en/speaker/speaker-chassis/167/d-165i-subwoofer-built-in-loudspeaker
I intend to use an active filter t.rack DSP 4x4 to adapt them to the main speakers.and power each one with separate class D amplifier.
That is my first active build and I'm unsure how much power I'll need for each driver as I'll boost them in 30-40Hz with 5-6dB. The drivers are with nominal power of 80W so I think 120-150W/4ohms will be enough for each of them. Which chip to choose : TPA3116 (120W/ch), TDA7498E (160W/ch), TAS5613 (150W/ch) or something else more/less powerful? Do I need preamp or the DSP will do this?
Also may I use single PSU for all of the amplifiers, or I'll need separate ones?
Thank you.
Last mount I bought 4 Reckhorn D165 drivers and I'd like to build four sealed subwoofers.
https://reckhorn.com/en/speaker/speaker-chassis/167/d-165i-subwoofer-built-in-loudspeaker
I intend to use an active filter t.rack DSP 4x4 to adapt them to the main speakers.and power each one with separate class D amplifier.
That is my first active build and I'm unsure how much power I'll need for each driver as I'll boost them in 30-40Hz with 5-6dB. The drivers are with nominal power of 80W so I think 120-150W/4ohms will be enough for each of them. Which chip to choose : TPA3116 (120W/ch), TDA7498E (160W/ch), TAS5613 (150W/ch) or something else more/less powerful? Do I need preamp or the DSP will do this?
Also may I use single PSU for all of the amplifiers, or I'll need separate ones?
Thank you.
Sounds like a lot of work, comparatively speaking, there are a lot of options.
Ideally I would say get two TAS6582 instead of a single TAS6584 because of the max rating is 400VA per chip, they are nice high frequency PWM amplifiers with some Class H rail magic thrown in the mix, not to mention good noise levels and digital input. They do supposedly have some DSP capabilities as well, but as it is right now I have not been able to find any ready made designs other than the EVM.
Been hoping @lutkeveld would catch some interest in those chips.
Edit: I would avoid TPA3116, look at TPA3251 or something comparable from other manufacturers.
Ideally I would say get two TAS6582 instead of a single TAS6584 because of the max rating is 400VA per chip, they are nice high frequency PWM amplifiers with some Class H rail magic thrown in the mix, not to mention good noise levels and digital input. They do supposedly have some DSP capabilities as well, but as it is right now I have not been able to find any ready made designs other than the EVM.
Been hoping @lutkeveld would catch some interest in those chips.
Edit: I would avoid TPA3116, look at TPA3251 or something comparable from other manufacturers.
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@KaffiMann, thank you for your advice.
I didn't find any pre made amplifier board based on TAS6582 and I don't have knowledge to build one, but there are couple of TPA3251 available.
https://www.ebay.co.uk/itm/22613355...E&toolid=10001&mkevt=1&gad_source=1&gclsrc=ds
Not sure how qualitative they are, but for a price of £25 I can't go wrong.
Do I need some preamplifier or I can plug them straight into the DSP output?
I didn't find any pre made amplifier board based on TAS6582 and I don't have knowledge to build one, but there are couple of TPA3251 available.
https://www.ebay.co.uk/itm/22613355...E&toolid=10001&mkevt=1&gad_source=1&gclsrc=ds
Not sure how qualitative they are, but for a price of £25 I can't go wrong.
Do I need some preamplifier or I can plug them straight into the DSP output?
The TAS6584/82 seems ideal for your use case, I am aware that there are no places you can buy it, merely raising awareness because it seems like nothing is happening with this very interesting chip.
No preamplifier needed between the TPA3251 and the t.racks 4x4 DSP.
Have fun.
No preamplifier needed between the TPA3251 and the t.racks 4x4 DSP.
Have fun.
With such small drivers, seems a perfect Sonotube build. With proper placement and a smaller room, this system should sound excellent. Remember to run one of the subs 180 degrees out of phase……you’ll have to experiment with which one in room for the smoothest response…..typically it’s the one closest to the listening position .
I will try a double bass array (DBA) with 4 subs - 2 on the front wall and 2 (inverted polarity) on the back wall.
As my room isn't rectangular (its open plan kitchen/living) I have some doubts about the result.
But who knows - if I never try I never know ;-)
As my room isn't rectangular (its open plan kitchen/living) I have some doubts about the result.
But who knows - if I never try I never know ;-)
Just bought Cloud CX-A6 six channel amplifier second hand.
https://www.cloud.co.uk/products/archive/cxa6-6-x-120w-amplifier
Hope it will meet the requirements.
https://www.cloud.co.uk/products/archive/cxa6-6-x-120w-amplifier
Hope it will meet the requirements.
Thank you for advising, Dave.
I'm not familiar with push-push configuration.
How it works? What are the benefits of that?
I'm not familiar with push-push configuration.
How it works? What are the benefits of that?
The arrangement of the drivers creates a box where there is active reaction force cancelationwhich removes most of the energy that would go into the box to cause resonance.
In a sub you do have to worry about ballooning.
As a proof of concept we made a pair of push-push 10” woofers with 15mm Baltic Birch. It was successfulk and works VERY well.
Bass at these frequencies is omni-directional. As long as within a quarter wavelength multiple woofers act as one and it matters little what directin you point them.
dave
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Opposed drivers cancel force that can cause a (relatively light) cabinet to move back and forth (vibrate) in response to the driver's mass shift.
The internal energy (sound pressure level, SPL) the drivers put in the box is not "removed" using opposed drivers, if it were, it's output SPL would be reduced.
Box resonant frequencies are determined by panel sizes and cabinet volume.
You do not have to "worry about ballooning" if the sub is adequately braced for it's dimensions and material used.
Art
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The mass shifts ar eequal & opposite so little moves. Unlike a sub with unbalanced driver reaction force.
No box walk as one can see with woofers just on the baffle.
Yes, one needs to adequately brace the box, both to halt ballooning, and to push box rresonances above the sytems bandwidth.
dave
Thank you Dave
Sorry for delay.
I'll need some time to understand the principle of that arrangement.
As I realised these two drivers are acting as a single spherical driver as far as the baffle width is less than a couple of meters.
I suppose the same effect we can see when the cabinet is placed against the wall. Then the wall reflection should act as a second driver causing boost upto 3dB.
The only benefit I see is reduced cabinet vibrations, which (I suppose) are negligible for 6.5 inch driver.
Maybe my assumptions are wrong. Thats why I'm looking for the opinion of more experienced people.
Sorry for delay.
I'll need some time to understand the principle of that arrangement.
As I realised these two drivers are acting as a single spherical driver as far as the baffle width is less than a couple of meters.
I suppose the same effect we can see when the cabinet is placed against the wall. Then the wall reflection should act as a second driver causing boost upto 3dB.
The only benefit I see is reduced cabinet vibrations, which (I suppose) are negligible for 6.5 inch driver.
Maybe my assumptions are wrong. Thats why I'm looking for the opinion of more experienced people.
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Benefits of dual opposed: its smaller then 2 subs stacking, with double the power 6db more dynamic range then a single woofer, more sensitive it play louder on low volume avr, less distortion, and no shaking or walking sub on full power.
I like dual opposed subwoofers a lot.
I like dual opposed subwoofers a lot.