One reason I personally like diy is I can measure every resistor and use ‘the good stuff’. Wouldn’t you wish eventually that you had not put in carbon resistors? 🙂
Many thanks for doing this Mr. Pass!
I recently, (yesterday!) landed on simple 3 filters EQ for a pair of Altec model 14s that yields a very similar curve, but a shelf at the low end vs a bell, but this looks very similar to this.
Does anyone happen to have an export of the Microcap file that might import into LT Spice? It's not a lot of components, but hoping to save a step.
Would love to model this out to see how close I can get to the below. (xover is LR 4th order @ 1.5khz on HP and LP)
(filters are: #6 low shelf +7db to 217hz (baffle step freq);
#1 adjustment for horn peakiness (-3.7db, Q 2.04 @ 3.75kHz)
#2 adjustment for CD/horn roloff + 4.4 db high shelf @ 10kHz, 6db slope --- I can't honestly even hear this one at my hearing levels, lol, but threw in as I was contemplating pllxo and would help with attenuation perhaps)
There's also 7db of attenuation on the HF, but I can manage this at the analog active crossover.
the resulting curve is as below, certainly there's room response in the FR below, but was happy with the simplicity. (ignore the pink filter, I was playing with the FR at the seating position.
I recently, (yesterday!) landed on simple 3 filters EQ for a pair of Altec model 14s that yields a very similar curve, but a shelf at the low end vs a bell, but this looks very similar to this.
Does anyone happen to have an export of the Microcap file that might import into LT Spice? It's not a lot of components, but hoping to save a step.
Would love to model this out to see how close I can get to the below. (xover is LR 4th order @ 1.5khz on HP and LP)
(filters are: #6 low shelf +7db to 217hz (baffle step freq);
#1 adjustment for horn peakiness (-3.7db, Q 2.04 @ 3.75kHz)
#2 adjustment for CD/horn roloff + 4.4 db high shelf @ 10kHz, 6db slope --- I can't honestly even hear this one at my hearing levels, lol, but threw in as I was contemplating pllxo and would help with attenuation perhaps)
There's also 7db of attenuation on the HF, but I can manage this at the analog active crossover.
the resulting curve is as below, certainly there's room response in the FR below, but was happy with the simplicity. (ignore the pink filter, I was playing with the FR at the seating position.
Thanks stevu! Much appreciated!
I have a windows 11/UTM virtual machine for installing Microcap installing the o/s in the background, so this is a substantial timesaver!
I have a windows 11/UTM virtual machine for installing Microcap installing the o/s in the background, so this is a substantial timesaver!
Quick question. Somehow R10 in the RCRC power filter got changed to 47.5k in the Excel parts list, instead of the 47.5 ohm value shown in the original schematic. So, I have a couple of 68 ohm resistors I could substitute for both R10s, or a 68R and then a 15R. That’s the closest I have without another order. Any advice?
Hi All, quick question. I see 0.5 watt resistors are recommended for this project. Is it also applicable for r10 and r11 resistors in power supply section?
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I ordered the kit and full range speaker. If I add a tweeter (I know my FR have high freq), can I still use the kit and do my adjustments or this kit is only for 1 FR speaker per channel?
If you plan to use a tweeter it's a good idea to use a crossover, either active or passive, to protect it from the full range signal. You can still use the EQ to smooth out any bumps that may be present in your FR.
Since this is a line level equalizer, if you want to avoid needing a second amplifier just for the tweeter, it is possible to use this with a full-ranger with an added tweeter.
Ideally, you want to make sure the tweeter falls outside the range of the high frequency cut. This depends on what frequency you choose to cross the tweeter (and therefore the value of the cap in that crossover) and the values of C3 and C4 in the equalizer circuit, which shift the peak of the HF cut higher up or down the frequency scale.
I'm guessing that it isn't necessary to completely avoid the treble cut curve, but just avoid having part of the frequency range of the tweeter right in the middle of it.
Ideally, you want to make sure the tweeter falls outside the range of the high frequency cut. This depends on what frequency you choose to cross the tweeter (and therefore the value of the cap in that crossover) and the values of C3 and C4 in the equalizer circuit, which shift the peak of the HF cut higher up or down the frequency scale.
I'm guessing that it isn't necessary to completely avoid the treble cut curve, but just avoid having part of the frequency range of the tweeter right in the middle of it.
Thank you Buckapound and to all. Well said and experimental fun and tweaks coming soon. I have also ordered the LX mini and will toy with it after the basic fr crossover. It will be fun working with active crossovers after my diy preamps/amps build (aca 1.8,acp+,fe 2023,aca mini).