Hey everyone,
This might be a silly question to some 😕 but I am a bit lost trying to find out what type of xover I need, my situation is my amps do not have outputs for subwoofers and I would like to add one to my system.
So the question is what sort of xover will I need? And would it go before or after my pre-amp?
Thanks!
This might be a silly question to some 😕 but I am a bit lost trying to find out what type of xover I need, my situation is my amps do not have outputs for subwoofers and I would like to add one to my system.
So the question is what sort of xover will I need? And would it go before or after my pre-amp?
Thanks!
Post up some more details about the system.
An active crossover would likely be the best option, it goes before the amplifiers and typically offers more control options.
An active crossover would likely be the best option, it goes before the amplifiers and typically offers more control options.
I was hoping to build something a bit versatile as I have multiple amps that I switch between, I have a class A valve pre amp (Muffsy BSTRD) and a Cambridge audio A5 amplifier at this time but will soon also have an EL34 Baby Huey Mono Blocks when they are finished!
Is that of any more help? 😕
Oh and a pair on KEF Q35 Floorstanders and the source varies from a tape deck, dac, phone, turntable...
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I picked up a NADY CX-225 stereo crossover with mono sub output, level controls, and crossover frequency controls for each channel. $50. Not hardly worth drilling a chassis for the connectors. Both XLR in & out & also 1/4 phone.
Can you explain what you mean by versatile? It could mean in level setting, dealing with different impedances.. The one you linked to doesn't have much information but if it does only 24dB/oct then it has limited versatility there.
I think I used versatile in the wrong sense I just want to be able to use it easily with different amps, adding a sub seems a bit more complex than I thought there doesn't seem to be much in the way of HiFi active crossovers they all seem to be Pro equipment...
Fame Audio X-Over MKII 19" Crossover | DV247 | en-GB
Fame Audio X-Over MKII 19" Crossover | DV247 | en-GB
I'm thinking any decent two way analog active crossover could be used. if using a single sub, Just sum the outputs of the low pass (ie tie both channels together) maybe put a couple of 1K resistors in line before the join (but probably not necessary).
Put it in between your preamp and your power amps. The other option is to go with stereo subs and a second stereo amp 🙂 then you don't need to worry about summing at all and you have some more flexibility with placement.
Tony.
Put it in between your preamp and your power amps. The other option is to go with stereo subs and a second stereo amp 🙂 then you don't need to worry about summing at all and you have some more flexibility with placement.
Tony.
There are about a million 🙄 of 'subwoofer filter' inside each of those 2.1 computer speakers that had invaded Earth since the late '90s.
The complexity varies, starting from 'summing resistors' for mono channel + simple RC for filtering ...to buffered inputs and the quad OP for LP and HP ( optional with very low power devices). The passive thingy ( the subwoofer driver in the enclosure ) makes the rest, be it a BR box, a bandpass box or whatever ( mainly, the placement under the desk...)
So I can testify: they really do exist ! And, if not found already made, the magic word this site consist of would suggest the answer, the path, the way...
Are you building a subwoofer or just using a commercial one. Most commercial subwoofer already have analog mixing and filter built in, so actually you don't need to do anything. If buying plate amps for subwoofer, already come with that too.
Oon
Oon
Thanks for the replies everyone, I'm still quite confused on the matter so many options but would some sort of simple splitter work if the sub has an amplate with controls or is it more complex than that?
If anyone can recommend something kit/pcb or something prebuilt?
If anyone can recommend something kit/pcb or something prebuilt?
The funny thing is you're right but at the same time it is more complicated. Maybe some more information...
If you were making a boombox then this crossover is fine. If you were making a home setup with a bandpass box then you might want to run all 3 full range. In another case you'd want separately variable filters.
If you were making a boombox then this crossover is fine. If you were making a home setup with a bandpass box then you might want to run all 3 full range. In another case you'd want separately variable filters.
Ok let me see if I can make myself a bit more clear/info (I apologize I am dyslexic & have ADHD so getting things out my brain and onto paper or in this case forum can be a bit all over the shot)
So my system as it stands is:
Source > Pre-Amp > Power Amp > Speakers
I would like to add a subwoofer to my system as my KEF Q35 floor standers don't quite go low enough for my taste.
None of my amps currently have a subwoofer output I have a little BSTRD Class A valve Pre amp, and a Cambridge Audio A5 integrated amplifier (it does have a Pre Out but I'm unsure what that is for? But it will soon be replaced by a pair of Baby Huey Mono blocks (when I eventually finish them 2 years in the making haha).
So I suppose I think I'm looking for the simplest way to add a subwoofer to this system, but with the amount of options is frying my head a little I'm a power supply technician so I can build things and understand some of the audio magic but for some reason this is really baffling me
I suppose I would like to be able to control the amount of bass that goes to the woofer easily or turn it of but for now I don't think I need any other controls unless some can be recommended.
I hope that's a bit more understandable?
So my system as it stands is:
Source > Pre-Amp > Power Amp > Speakers
I would like to add a subwoofer to my system as my KEF Q35 floor standers don't quite go low enough for my taste.
None of my amps currently have a subwoofer output I have a little BSTRD Class A valve Pre amp, and a Cambridge Audio A5 integrated amplifier (it does have a Pre Out but I'm unsure what that is for? But it will soon be replaced by a pair of Baby Huey Mono blocks (when I eventually finish them 2 years in the making haha).
So I suppose I think I'm looking for the simplest way to add a subwoofer to this system, but with the amount of options is frying my head a little I'm a power supply technician so I can build things and understand some of the audio magic but for some reason this is really baffling me
I suppose I would like to be able to control the amount of bass that goes to the woofer easily or turn it of but for now I don't think I need any other controls unless some can be recommended.
I hope that's a bit more understandable?
Getting clearer. My first question would be, do your KEF speakers ever have a problem with the power you give them?
The reason
Subwoofers can be better running in parallel with your mains, as the reason for not enough bass can be both main speakers that are small, and also room modes.
Suggestion
Make sure your main speakers are well located. Mix the outputs from your preamp for the sub amp, for example buffering and combining, while leaving stereo for your mains. Make sure you have a way of controlling the level of the bass, and that it is within range. See that you can cross the bass, either speaker level passive low pass, or line level.. possibly active and possibly with some EQ.
The reason
Subwoofers can be better running in parallel with your mains, as the reason for not enough bass can be both main speakers that are small, and also room modes.
Suggestion
Make sure your main speakers are well located. Mix the outputs from your preamp for the sub amp, for example buffering and combining, while leaving stereo for your mains. Make sure you have a way of controlling the level of the bass, and that it is within range. See that you can cross the bass, either speaker level passive low pass, or line level.. possibly active and possibly with some EQ.
You make a very good point there about are the speakers getting enough power while we have been chatting I have stripped down my Amp and found a mass of salt corrosion (the previous owner was a surfer and left it in his garage! The SAP15 Transistors look ok only 1 had corrosion around it so I will have to test them but have found a blown ceramic cap and blown resistor I cant believe the amp was working at all!
When you say mix the signals and buffer and combine how would I do this? With an op amp and summoning circuit? or is there something out there that does this?
When you say mix the signals and buffer and combine how would I do this? With an op amp and summoning circuit? or is there something out there that does this?
Sure, I mean you could tap off a mono signal with a couple of resistors but in order to maintain the stereo signal you might need to buffer it. You can use op amps or something else. The board you linked to above appears to be doing at least this (I haven't looked closely at it), then we got onto the question of filters.
Filters... I take it this is where the fun begins! 😱
The one I linked says its a Linkwitz-Riley with default crossover frequency is 125 Hz
The one I linked says its a Linkwitz-Riley with default crossover frequency is 125 Hz
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I've been trying to maintain suggestions for these. For the mains... at the least, nothing. At the most, trim the low end to increase power handling. For the subs... at the least for a bandpass box, nothing. At the most, variable low pass frequency, variable low pass slope, level, polarity and parametric EQ(s).