rawatch
Active member
thinking of replacing the woofer and maybe converting to active sub in my quest z speaker, i don't think they are fast or deep enough for me
any thoughts?
any thoughts?
replace bass quest z speakers
- Thread starter rawatch
- Start date
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Yep, by now the original woofer is likely toast, and needs to be replaced anyway. Going active gives you many more options for replacement drivers, and may even allow you to further optimize by using an actual sperate subwoofer for the very low-end.
I did that with my Monoliths, and it was a great outcome, see my system and other threads I've posted on the subject.
With a Quest, the biggest challenge is to bypass the passive crossover to the panel, which means pulling out the crossover and doing the mods, as seen on the Quest Z schematic, the bypass is not that hard.
1. Remove 100% of the crossover elements between the low-input and the 12" woofer driver, just a basic wire goes there. Simple.
2. On the High-In, disconnect the + output, and connect a new lead from it to the input of R4 (you want to keep some resistance to keep the amp happy).
2.1 Cut the output of C4
2.2 Cut the Input to R4 from the old network
2.3 For extra power handling, parallel the other 2 3Ohm resistors with R4, which means cutting them out and repositioning so you can parallel them
Basically, the panel gets the input from the active crossover high-pass, via the power amp, then goes through the 3 Ohm 60W (three paralleled 20w resistors) and into the step-up transformer.
You must own and know (or learn) how to use an audio measurement rig like REW. If you read my posts on mods or my custom center channel build, you will understand why that is non-negotiable. Tuning an active crossover setup is impossible without it.
As for active crossover, you could go simple with a MiniDSP HD (REW Supports it, so easy to download suggested EQ and crossovers), or for really flexible, robust and very clear results, something like a DriveRack Venue360 would be best. The 360 has enough outputs to also allow for multiple subwoofers to be managed as well.
What is your level of technical expertize?
I did that with my Monoliths, and it was a great outcome, see my system and other threads I've posted on the subject.
With a Quest, the biggest challenge is to bypass the passive crossover to the panel, which means pulling out the crossover and doing the mods, as seen on the Quest Z schematic, the bypass is not that hard.
1. Remove 100% of the crossover elements between the low-input and the 12" woofer driver, just a basic wire goes there. Simple.
2. On the High-In, disconnect the + output, and connect a new lead from it to the input of R4 (you want to keep some resistance to keep the amp happy).
2.1 Cut the output of C4
2.2 Cut the Input to R4 from the old network
2.3 For extra power handling, parallel the other 2 3Ohm resistors with R4, which means cutting them out and repositioning so you can parallel them
Basically, the panel gets the input from the active crossover high-pass, via the power amp, then goes through the 3 Ohm 60W (three paralleled 20w resistors) and into the step-up transformer.
You must own and know (or learn) how to use an audio measurement rig like REW. If you read my posts on mods or my custom center channel build, you will understand why that is non-negotiable. Tuning an active crossover setup is impossible without it.
As for active crossover, you could go simple with a MiniDSP HD (REW Supports it, so easy to download suggested EQ and crossovers), or for really flexible, robust and very clear results, something like a DriveRack Venue360 would be best. The 360 has enough outputs to also allow for multiple subwoofers to be managed as well.
What is your level of technical expertize?
rawatch
Active member
I am ready to do this built a st120 tube amp for the top end and a classe ca 200 for the woofer and a ml depth i sub, going to use a minidsp hd rew software
you mention downloads for dsp?
is it better todo the sub and woofer or the quest z alone and adjust the sub with its controls?
you mention downloads for dsp?
is it better todo the sub and woofer or the quest z alone and adjust the sub with its controls?
