Extract: Can I incorporate a simple amplification circuit in a HF crossover to boost a tweeter a few db to match the sensitivity of a compression driver mid instead of using an Lpad on the compression driver mid to match the sensitivity of the tweeter?
Hi I'm building/experimenting with a two and three way bi amplified system incorporating active and passive crossovers. I'm using a MiniDSP Dac sending an active crossover signal to a Ncore amp feeding a 15" woofer. That same dac feeds a tube amp powering a compression driver which covers the upper registers.
I'm interested in enhancing the treble by adding a tweeter (bullet tweeter, 1" cd, etc.). I would prefer to keep things simple and incorporate a passive crossover if possible. That said the compression driver mid (in a three way configuration) is anywhere from 3-8db more efficient than the tweeter I would be using. I'm curious if instead of using an L-Pad on the mid compression driver...
Can I incorporate a simple amplification circuit in a HF crossover to boost the tweeter a few db to match the sensitivity of the compression driver mid? If so what is a product that you recommend? The simpler the better -- something like this is ideal assuming it's not to crappy: https://www.htd.com/LGB-1.
Thanks.
Hi I'm building/experimenting with a two and three way bi amplified system incorporating active and passive crossovers. I'm using a MiniDSP Dac sending an active crossover signal to a Ncore amp feeding a 15" woofer. That same dac feeds a tube amp powering a compression driver which covers the upper registers.
I'm interested in enhancing the treble by adding a tweeter (bullet tweeter, 1" cd, etc.). I would prefer to keep things simple and incorporate a passive crossover if possible. That said the compression driver mid (in a three way configuration) is anywhere from 3-8db more efficient than the tweeter I would be using. I'm curious if instead of using an L-Pad on the mid compression driver...
Can I incorporate a simple amplification circuit in a HF crossover to boost the tweeter a few db to match the sensitivity of the compression driver mid? If so what is a product that you recommend? The simpler the better -- something like this is ideal assuming it's not to crappy: https://www.htd.com/LGB-1.
Thanks.
Does your DSP have a shelf filter / EQ you could use to boost the treble before the passive crossover ?
That's just an op amp with a little gain, it would feed a load of 1k ohm and up, not a driver.
You would need a power amplifier to do something similar for the tweeter.
You would need a power amplifier to do something similar for the tweeter.
Good call SpeakerBob and thanks for clarifying Rayma. What sort of power amplifier do I need to boost a tweeter from 105db to 110db sensitivity?
A practical approach is an LPAD on the midrange to drop the sensitivity sufficiently to allow the tweeter and mid-range CD to work well together. This need not be adjustable and could be built with resistors.
Depending on the DSP you could add a shelving high pass in the DSP to boost the cross over output in the region the tweeter covers, but you should add an inductor in series with the mid driver in addition to the series cap to the tweeter to actually cross to the tweeter.
The best solution might be to add a third amplifier to drive the tweeter.
I have a MiniDSP SHD feeding 3 way line level analog cross overs to 3 power amplifiers per channel. The SHD here does EQ for room and speaker system.
Depending on the DSP you could add a shelving high pass in the DSP to boost the cross over output in the region the tweeter covers, but you should add an inductor in series with the mid driver in addition to the series cap to the tweeter to actually cross to the tweeter.
The best solution might be to add a third amplifier to drive the tweeter.
I have a MiniDSP SHD feeding 3 way line level analog cross overs to 3 power amplifiers per channel. The SHD here does EQ for room and speaker system.
A separate power amp does not change the sensitivity of the tweeter. Adding a power amp with more voltage capability than your present tube amp is not simple.
A passive compensation/crossover circuit can be made to increase the high frequency sensitivity of a driver, here is an example for an EV DH3/HPT94 horn that increases the sensitivity from 105dB to 110dB at 15kHz, using three components (2uF, 6uF capacitors, 0.12mH inductor).
I added the EV DH3/HPT94 xover/EQ on top a 16ohm JBL 2445J/2380 for a deaf bass player vocal monitor, and it came close to the midband sensitivity, flattening response out to well past his hearing capability 😉.
At any rate, with the EQ available in the MiniDsp, if you put a passive LP on your mid driver, there would be no need to pad the mid down adding a tweeter.
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