Making Paradigm Studio 40's active utilizing Hypex plate amp.

[Thunder22]

I have a pair of Paradigm Reference Studio 40's that I would like to make active. They are an 8 ohm, 3 driver, 2-1/2-way passive speaker. Way back when Paradigm also released an active version that was discontinued soon after.

Passive version specs:
Power Handling (RMS):180 WattsFrequency, Response:59Hz - 22kHzSensitivity (dB):91dB

Active version specs: There are two solid-state amplifier modules in each Active/40 speaker: 50 watts for the tweeter and a 125 watts for the midrange/woofer section. Paradigm claims +/- 1dB from 22kHz down to 36Hz.

2-1/2 way? The Active/40 is a 2.5-way design. What this means is that both woofers operate through the lowest frequencies to give the best bass possible. But as the frequency increases, one of the drivers is rolled off and the other travels into the midrange region by itself. The tweeter handles what’s above all that. The crossover is a third-order design with the main crossover point at 1.5kHz. Additionally, one woofer crosses electro-acoustically at 400Hz, while the other woofer handles everything up to 1.5kHz.

My questions are...

1- Can I use a Hypex Fusionamp to accomplish this ?
1a- If so would I need to get a 2-way or a 3-way considering that I would like to copy what Paradigm has done with the midrange.

Apparently the drivers are the same between the two versions, but in my investigation I have noticed that the rear ports are in a different configuration. In order to fit the amp I will have to move one of the ports to the bottom anyway, but I'm not sure if the internal cabinet bracing is different. 2- Does anybody know?

Most information above regarding the Active/40's was taken from a review by Doug Schneider. http://www.soundstagenetwork.com/revequip/paradigm_active40.htm

Thanks,

Travis

 

[Hon]

It appears that the two woofers are joined by a passive crossover and together make up one active section, and the tweeter is separate and powered by the other active section. So you need two channels for each speaker. You could dissect the existing passive crossover where it divides the woofer pair from the tweeter at 1.5k and then insert the amplifiers. But you ultimately want to remove the passive crossover section at 1.5k and instead run an active crossover ahead of the amplification. Maybe there's a plate amplifier that would help. The two ports may be more problematic than you'd like; you'll have to open the box and scope out the layout to see how the woofers relate to each other and to the ports.

 

[Thunder22]

It appears that the two woofers are joined by a passive crossover and together make up one active section, and the tweeter is separate and powered by the other active section. So you need two channels for each speaker. You could dissect the existing passive crossover where it divides the woofer pair from the tweeter at 1.5k and then insert the amplifiers. But you ultimately want to remove the passive crossover section at 1.5k and instead run an active crossover ahead of the amplification. Maybe there's a plate amplifier that would help. The two ports may be more problematic than you'd like; you'll have to open the box and scope out the layout to see how the woofers relate to each other and to the ports.

Thank you for your reply. Since I would rather not dissect the existing crossover( in case the entire project ends up sucking and I keep it passive) would it be wise to make it 3-way ?

 

[Thunder22]

Also, if anybody has other ways/product recommendations in order to accomplish this I would appreciate it. Sometimes just a point in the right direction can be helpful.

 

[Hon]

Here's a well-documented Studio 40 project that might give you some insight and/or courage to dive in: Studio 40 Mod
You can see that the crossover to the tweeter is simple enough, but the woofer(s) side is a bit more complicated, with some compensation.
If this description is correct (Active 40), Paradigm's active version retains the passive crossover and merely inserts separate amplification for each leg of the crossover. That would be the same as external "bi-wiring" with two amp channels per speaker. If Paradigm were utilizing active eq and networking at the amplification stage, they wouldn't need (want) the passive crossover components. You might achieve better results with fewer headaches by just following the "Studio 40 Mod" and using a good old-fashioned external amp.

 

[Vince2]

I would actually use a 3 way hypex and give each woofer a separate channel. Remove the cross over and accomplish the same by shaping the fr of each woofer using the eq of the hypex dsp. Assuming you have a measuring mic and familiarity using rew.

 

[Thunder22]

I would actually use a 3 way hypex and give each woofer a separate channel. Remove the cross over and accomplish the same by shaping the fr of each woofer using the eq of the hypex dsp. Assuming you have a measuring mic and familiarity using rew.

This is what I was leaning towards. Thanks. A lot of the Hypex plate amps are sold out. Maybe they require pre-orders before they build them. Any other gear recommendations?

 

[Vince2]

Madisound is the distributor in the US.

 

[Thunder22]

Madisound is the distributor in the US.

Word

 

[Cbdb2]

I would actually use a 3 way hypex and give each woofer a separate channel. Remove the cross over and accomplish the same by shaping the fr of each woofer using the eq of the hypex dsp. Assuming you have a measuring mic and familiarity using rew.

You dont need the mic. Measure the output freq response of the existing xover at each driver and recreate with active DSP.

 

[Thunder22]

You dont need the mic. Measure the output freq response of the existing xover at each driver and recreate with active DSP.

If not using a mic, how do i measure the frequency response?

 

[Cbdb2]

This will recreate the existing xover it wont fix any freq response problems already there, if you want to do that you still need a mic. Volt meter on each driver and a freq sweep.( set the amp to 1 volt out). This will tell you what the existing xover is doing. I did this with a pair of book shelfs and was surprised how unflat it was for a fairly flat acoustic output.

 

[Cbdb2]

Heres what I got. Its a log log scale. You can see how uneven it is to make up for the drivers and the tweeter is 6db lower than the woofer.

 

[somebodyelse]

If you use a volt meter make sure it's one that works at the necessary frequency - many ordinary multimeters aren't accurate above 400Hz or so. If you've got an audio interface with line inputs you can use REW - you'll need an attenuator to stop the speaker amp overloading the line inputs. If your power amp has bridged outputs (neither output is connected to amp 0V) you'll need a more complicated attenuator to avoid damaging anything, so make sure you understand what's what.

 

[Cbdb2]

Yes thanks for mentioning that. An osciloscope also works if you have one.

 

[Thunder22]

If you use a volt meter make sure it's one that works at the necessary frequency - many ordinary multimeters aren't accurate above 400Hz or so. If you've got an audio interface with line inputs you can use REW - you'll need an attenuator to stop the speaker amp overloading the line inputs. If your power amp has bridged outputs (neither output is connected to amp 0V) you'll need a more complicated attenuator to avoid damaging anything, so make sure you understand what's what.

Thanks for the heads up on the multimeter. I'll have to check what mine are capable of. I've never used any of them for audio.

 

[Thunder22]

Yes thanks for mentioning that. An osciloscope also works if you have one.

An oscilloscope would be nice, but I don't have one. Again, thanks for the suggestions, but I think I'll be taking the route of investing in a mic and going the REW route.