Hey all,
I'm hoping someone with prior hands-on experience can help me. I'm considering a 3 way using a Hypex 3-way active plate amplifier and ScanSpeak components. For the midrange I can pick either a 4 or 8 Ohm driver which is broadly equivalent except the usual: The 4 Ohm version has 3 dB more output at the same voltage. 87 vs. 90 dB.
The 4 Ohm has a minimum Z of just around 3.6 Ohms, while the 8 Ohm has a minimum Z around 7.5 Ohms.
Given this is an active design, and my choice of amplifier, and equivalent maximum power handling (80W) for both, is there a reason not to use the 8 Ohm version? My inclination is to think that this plate amp will do better > 4 Ohms than below so I should stick with the 8 Ohm version.
Thoughts?
Thank you,
Erik
I'm hoping someone with prior hands-on experience can help me. I'm considering a 3 way using a Hypex 3-way active plate amplifier and ScanSpeak components. For the midrange I can pick either a 4 or 8 Ohm driver which is broadly equivalent except the usual: The 4 Ohm version has 3 dB more output at the same voltage. 87 vs. 90 dB.
The 4 Ohm has a minimum Z of just around 3.6 Ohms, while the 8 Ohm has a minimum Z around 7.5 Ohms.
Given this is an active design, and my choice of amplifier, and equivalent maximum power handling (80W) for both, is there a reason not to use the 8 Ohm version? My inclination is to think that this plate amp will do better > 4 Ohms than below so I should stick with the 8 Ohm version.
Thoughts?
Thank you,
Erik
If you're using one of the FusionAmp plates, then the DSP in the amp module will let you select different gains for the different drivers. In that case, sensitivity differences of a few dB are easy to account for.
Disclaimer: I have no experience with Hypex. I've built other active speakers with DSP driving each driver separately: The Darbari
Disclaimer: I have no experience with Hypex. I've built other active speakers with DSP driving each driver separately: The Darbari
Hi,
My experience with Hypex gear is they are insensitive to load. I never used a fusion amp however.
My experience with Hypex gear is they are insensitive to load. I never used a fusion amp however.
Hypex nCore class D amplifiers seem quite happy with 4 ohm loads, or even lower. The FA-252 is rated at 250 W at 4 ohm, and 150 W at 8 ohm, and this implies that the limiting factor is output voltage ,not current.
The Hypex NC400 module is very similar to the modules used in the fusion plate amps. The NC400 module has been tested and found to be stable into 2 ohm loads. Stereophile tested the NAD M22 power amp, which uses the NC400 module and found it delivered 340 W into 8 ohm, 570 W into 4 ohm, and 700 W into 2 ohm (all at 1% distortion threshold). https://www.stereophile.com/content/nad-masters-series-m22-power-amplifier-measurements
I have used both the FA253 and FA123 with 4 ohm drivers... I am very pleased with the performance.
The Hypex NC400 module is very similar to the modules used in the fusion plate amps. The NC400 module has been tested and found to be stable into 2 ohm loads. Stereophile tested the NAD M22 power amp, which uses the NC400 module and found it delivered 340 W into 8 ohm, 570 W into 4 ohm, and 700 W into 2 ohm (all at 1% distortion threshold). https://www.stereophile.com/content/nad-masters-series-m22-power-amplifier-measurements
I have used both the FA253 and FA123 with 4 ohm drivers... I am very pleased with the performance.
You get 3 dB lower noise floor with the 8 Ohm driver (if the 87 dB vs 90 dB voltage sensitivity is true).
Just want to add that while you can put a 2ohm load on Hypex NC amps with no problem, you shouldn't run them in bridge-tied mode with a 4ohm load. Not exactly sure why, but this is stated in the data sheet. The amps are rated for more power at 8ohm BTL than 4ohm BTL.
Because the 8 Ohm BTL power comes from what the bridged amps can delivers into 4 Ohm individually, and BTL power into 4 Ohm comes from what the amps can delivers into 2 Ohm individually etc.
BTL with Hypex FAs worth only if the speaker impedance is 8 Ohm or higher and you really need that approx +3 dB max volume compared to normal mode and you are willing to sacrifice one amp channel for this.
BTL with Hypex FAs worth only if the speaker impedance is 8 Ohm or higher and you really need that approx +3 dB max volume compared to normal mode and you are willing to sacrifice one amp channel for this.
Hypex is a brand with a reputation for producing amp modules being load independent. My particular experience is with their older UcD modules inside my amp and according to the data sheet they can handle 1 Ohm!
That’s correct.
8/4/2 ohms all stable.
They are just current limited; which means they won’t “double down” from 1/2/4/8 watts perfectly.
8/4/2 ohms all stable.
They are just current limited; which means they won’t “double down” from 1/2/4/8 watts perfectly.
So asked another way,
In this case, it states the maximum output power is equivalent at 4 and 8 Ohms, but not anything on output impedance.
PS -I'm absolutely not bridging anything. 😀 I'm making a 3-way center. I'll use 2x 8 Ohm woofers in parallel, and it seems an 8 Ohm mid and tweeter as well.
I'll use the Hypex 3-way plate amplifier to power each section independently. I'll attempt 4th order LR aligned (electro-acoustical of course) filters.
I'll use the Hypex 3-way plate amplifier to power each section independently. I'll attempt 4th order LR aligned (electro-acoustical of course) filters.
I used a FA123 with 2.7ohm speaker for years with no issues, and used the basic settings to adjust for impedance.
Logically thinking, the lesser demand for current is a better way. Did I understand right, you are to use a 3 way, 3 channel, dsp x/o, each channel powering one of the drivers? What exact model is that Hypex plate amp product?
Why is Zout important for your purpose? Usually, we have been seeing solid state amps' Zout (Class B and Class D) to be at least two orders of magnitude lower than the speaker load, therefore does the precise Zout matter?
In one application, I use an FA-123 to drive (1) a pair of 8 ohm 8" woofers in parallel, with a net Re of 3.1 ohm (2) a 4 ohm mid driver with an Re of 3.1 ohm (3) a 4 ohm tweeter with an Re of 3.2 ohm. No problems at all.
In the other application I use an FA-253 to drive (1) a 12" woofer rated at 6 ohm, with an Re of 4.2 ohm (2) a 4 ohm mid with an Re of 3.4 ohm (3) a 4 ohm tweeter with an Re of 3.0 ohm. Again, no problems, even when filling a very large room (10,000 ft^3) with sound.
In the other application I use an FA-253 to drive (1) a 12" woofer rated at 6 ohm, with an Re of 4.2 ohm (2) a 4 ohm mid with an Re of 3.4 ohm (3) a 4 ohm tweeter with an Re of 3.0 ohm. Again, no problems, even when filling a very large room (10,000 ft^3) with sound.