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Audiotechnical conundrum

Hello sir/madam,

I have 2 speakers with 2 cables coming out and 1 subwoofer Alpine SWE1243E. I though I could attach them to my Douk Audio Pre-amplifier Well it seems like that I can’t because there is no space for the sub woofer so I thought about buying a https://www.aliexpress.com/item/4000169356588.html?spm=a2g0o.cart.0.0.77413c00NXQdQl&mp=1 Thought about having it under my existing dac so I can also have audio from my computer being played to the speakers.

But the subwoofer also just has 2 cables out and I really don’t know anything about Audiotech so, please help.

Can you post a picture of the connections on the back of your subwoofer? Some subwoofers will have input and output connections with the intention of running audio to the sub first, then from the sub to the speakers/speaker amplifier.

https://linksharing.samsungcloud.com/UbIlcw3jyZoN

There is now one of the speakers and the subwoofer

Hmm, have you tried driving those [passive] speakers with your preamp? Looking at the product page, I’m not exactly sure what the douk will do, but typically a preamp would only have enough power to supply headphones or active speakers. Is your subwoofer active (powered)? When working with passive systems you need to pay attention to overall power/wattage delivered at what impedance/resistance, and what the speaker is designed to handle/require.

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Okay, that answers some questions.

Next, do you have a cabinet of some sort for the sub? You’ll need one if you want any bass out of it.

Second, I would actually suggest a 2.1 amplifier to power everything. What you have are passive speakers and a passive subwoofer, meaning none of them have built in amplifier. Like @astra said, pre-amps don’t have anywhere near enough power for speakers/subwoofers, so you’ll need something extra.

That second item you linked in the OP looks like it would power your speakers (via the two sets of binding posts), but not the subwoofer. I’d recommend looking for something like a Lepai LP-168HA or similar. Searching “Douk 2.1 amplifier” on Aliexpress seems to be returning stuff that would work.

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To better understand what you are looking at, it would help to know where the music is coming from (as in: Computer with 1/8 jack and optical, phone via bluetooth, TV with SPDIF and optical, etc).

Like @astra mentioned, you need to pay attention to the power ratings.
The sub is 4 Ohm, 250W RMS, 800W peak

I take the speakers do not have a watt or impedance rating on them?
If you have a multimeter on hand, hold that accross the wires coming out the speakers. Should be somewhere between 2 and 8 Ohms (± 2 Ohm)


From the pictures of the speaker and sub, you need an amplifier (or two). One for the speakers, one for the subwoofer.

Suggestion

One easy option would be the SMSL AD18 for the speakers and feeding the amplifier for the subwoofer from the sub-out.
Make sure to get the version with the port marked “coax opti1 SW” as shown in this image:


In that you plug in a 1/8 to RCA cable, the red one going to the amplifier for the subwoofer.

To power the subwoofer, something like a Crown XLi800 or Behringer A500 will do the job.

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Most Home Audio subs have a crossover and passthrough so that a stereo signal can be sent into a sub and then split out to the L/R channels.

This would entail having a powered sub with the appropriate connections.

For example, it would look like this: https://cdn.thewirecutter.com/wp-content/uploads/2019/06/subwoofers-2019-lowres-7331-630x420.jpg

More advanced ones will have a SPDIF input for LFE, but then you’re getting into multi channel setups.

To the topic at hand, to do what you want with what, you have you’ll need a separate amp, with cross over for the sub, and possibly a separate amp for the L/R speakers. This can be a PITA for various reasons, and can get expensive quickly. You’ll also need a box/tube for the sub, and boxes for the speakers if they are not already mounted/enclosed.

So the usage would be Home audio setup like the one which Wendell in one of his podcasts mentions a diy such one. The sub woofer will get somewhat like a configuration of the Genelec subwoofer.

For now I don’t have a tv so the setup would be connected to my pc with rca to aux 3.5 I would have the the dac that I have would be used for headphones and desktop speakers. (Connected with usb)

I saw that the douk(the one linked) could do 300w, I don’t know the specs of the speakers but they work with my fathers radio thingy which also had the vinylplayer coupled to it.

Well the problem here is, I bought some rca cables so I’d have to cap the heads and try to fit them onto one of the cables hanging. Then hope for the right cable?

I could buy a suggested 2.1 amp but I’m looking to do 7.1 when I get more speakers and a TV.

Unless you’re really into the electronics of making different things work together it is generally cheaper and easier to get a 2.1 system for a PC. The higher end ones are around $200 US. Admittedly the Audio Gear side of things can be fun.

If you know that 7.1 is your goal you can get a 7.1, or greater, AVR and run your signal out via HDMI and then the video back to any source with HDMI from any of the outs on the AVR. The system can be configured to do anything from stereo/2.1 to as much as 14.2, 9.4.2, depending on how much you’re willing to spend or how much you’re into audio. SPDIF/Optical also works, but you can run into problems when it comes to bitstreaming multichannel sound, in my experience.

A cheap but good 5.1 set of speakers, like from Polk Audio, is generally around $200 ish (you can obviously spend more or buy piece by piece which does add up it’s all preference) and includes a sub and all your satellite monitors; you’ll just need speaker wire and an AVR obvsiouly.

The biggest challenge of doing the AVR system setup is learning how to config media players to bitstream multi channel sources.

I have the Douk audio pre amp already for my desk, I don’t need a subwoofer here, so it is fine. But wondering what I need to get the speakers and subwoofer to work.

I’m going probably to get some cheap used speakers later for 5.1 but this first.

Don’t. Surround sound is fun … for an hour or so. But if you have a limited budget better invest in a solid stereo setup than into cheapo surround.

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I already have solid speakers and a subwoofer…

You need something like this: https://www.amazon.com/gp/aw/d/B07PJVM79X/ref=psdcmw_537344_t1_B077QPTPVW

That’s an (actual) amplifier.

The way you wire the whole thing is: PC/source -> preamp (your Douk) -> amplifier -> 2 speakers and the subwoofer.

The link does not work.

but then again, what cables do I need to use, how do I wire the subwoofer and the speakers?

Is this amplifier enough? https://www.aliexpress.com/item/4000242289184.html?spm=a2g0o.productlist.0.0.4219f761sfnX1H&algo_pvid=3245039c-df85-4906-99fd-2dca69e1247a&algo_expid=3245039c-df85-4906-99fd-2dca69e1247a-0&btsid=0b0a0ae215938884355921898e5d2e&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_

Some useful info on pairing amps and speakers here: https://www.qacoustics.co.uk/blog/2017/08/14/beginners-guide-matching-speakers-amplifiers/

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Yeah, that one would work, too. You’d even have spare channels for the future (or you could hack a more powerful stereo output for fun). They’re all basic amps on some TI or Phillips chips.

Wiring… It’s really not complicated but how do I explain it. You can find a lot of good articles/videos online.

Your basic 3.5mm output/jack has three wires - left channel, right channel and ground. That’s what you’re working with.

You basically connect those to the preamp, to the amp, to the speakers, using 3.5mm->RCA adapters or custom made cables.

Not exactly sure why you would choose to try and power a 5.1 system from that ?

You need a creditable full on 5.1 receiver.

Something to expand the info base.

Correction…surround is great when done well. Which is not most things.

Do more research ! Something things are way easier than that and other things are far more complicated than you can imagine. Politics , DRM, bit rate and bit depth. There exists in this day and age 2.1 systems that can do a fairly decent job of giving you a much fuller surround like sound stage. Even give you depth…

Investing in a powered subwoofer can and does save effort and headaches.