Reddit reviews PAC LC-1 Remote Amplifier Level Controller

The tone knob has to be the most useless adjustment in the history of electronics. No matter where you turn it, the music still sounds like crap.

The closest thing available today would be a bass knob, which some subwoofer users prefer to adjust bass levels on the fly. A bass knob is mounted on the dash of the vehicle separate from the head unit. https://www.amazon.ca/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O

Honestly, a properly designed and tuned system and clean audio sources will be far more enjoyable than constantly fiddling with settings.

Look for a passive volume controller. They can be as cheap as around $10 if you do not care for aesthetics or Schiit SYS if you want something nicer.

If you have the space for it a 5.1/7.1 home theater receiver will actually provided the easiest, cheapest, and best subwoofer integration since it's guaranteed to implement a proper crossover that high-passes the C-Notes (improving their power handling and clarity about the xover point) and low-passes the subwoofer. Accessories4Less is reliable and has great refurb deals. They'll also put out more clean power than your typical compact Class D amp.

Of course, there's not always space for something like that.

Compact amps with subwoofer out are annoyingly hard to find. The SMSL AD18 and Q5Pro have subwoofer output, but are a bit pricy. They don't get super super loud, but should be plenty loud enough for practice or as monitors I guess! Keep in mind that their sub outs aren't high-passed so the C-Notes will still play full-range.

Alternately you could choose any old amp, and simply control the volume upstream from the amp. Then you won't need a subwoofer out on the amp.

(RCA splitter) --> (inline volume control) --> (piano)

The amp would go into one set of RCA outputs and the sub into another.

You could of course skip the inline volume control if you can simply do it on the piano!

> Main goal is to get distortion free power that won't starve the speakers, so I'm thinking it should probably put out 40 watts per channel at a minimum? I could be wrong there, parts express has the cnotes rated at 60 watts RMS.

If you're going with a class D amps in the $100 range, look for amps rated at around 100W per channel -- typically based on the TDA7498E like the SMSL SA98 and Topping PA3. That "100W" rating is at 10% distortion. However, they'll do 50W at nice low distortion levels, giving the C-Notes about as much clean power as they can take.

However, if you're just using these for practice from a distance of several feet you don't need to go that big. A "50W" class D amp will give you around 25W of actual clean power, which is pretty damn loud at close range and is only ~3dB less than a 50W amp and 6dB less than a 100W monster.

If you don't want to constantly be reaching behind the monitors to adjust the level knob, you will need a passive volume control (attenuator) like this:

http://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O/

This is what you want to get audio to your speakers, it's called a DAC, (better, more expensive options are available, but that's the best you're gonna do for under $100 lol) and this is the cable to connect the two devices (you'll also need RCA cables)

This will get you video to your projector.

Unfortunately since it looks like you're using powered monitors, you'll need a pre-amp to control the volume.

You may be thinking wow that's a lot of stuff, and it doesn't even come with a remote! And you're absolutely right. Unfortunately, the only thing that does all that is a full blow receiver, which get quite expensive and are usually aimed at surround sound systems. Most receivers don't like powered monitors though, so you'd have to get a very special one.

This is where you realize that passive speakers are what you really want, and you blow hundreds of dollars on speakers and equipment and you become an audiophile. Luckily there's a bunch of guides to get you started over on /r/zeos. But the stuff I listed earlier should let you jerry-rig a working set up while you save up :P

This will adjust the voltage of the pre amp.

You almost definitely don't need an external DAC. If the one built-in to your PC or laptop doesn't have audible noise or other issues, it's essentially a waste of money. And cheap integrated DACs, as long as the implementation isn't screwed up, can be transparent to big dollar ones... it's the absolute last place to spend money when trying to improve audio quality - far behind speakers, room treatments, and source file quality.

I personally am wary of the LSR 308s. Noaudiophile (/u/strategicdeceiver) is working on their review and has mentioned many times now that the large enclosure is too paper-thin and makes it sound worse than the 305s.

You could spend the extra money on an analog potentiometer for proper and convenient volume control. Something like this, or an Emotiva control freak, or Schiit sys.

Some put it on the front of the cab below the control deck. You will have to find a way to mount it so it stays. I put a shelf in mine. Doing that you could easily set it on the shelf as a way to mount it.

Another option is to do the volume mod and use the existing volume control to do mute/low/high (https://github.com/dmanlfc/arcade1up/tree/master/Raspberry%20Pi) *I'm posting how to do this with ODROID/Retro Arena soon.

Finally, what I'm doing is I ordered this: PAC LC-1 Remote Amplifier Level Controller https://www.amazon.com/dp/B0002J226O/ref=cm_sw_r_cp_apa_i_cHdYCbJ5BCF0J and either going to replace the volume switch with this or put it under the control deck.

Hope this helps :)

Sounds like you're looking for PAC LC-1 Remote Amplifier Level Controller https://www.amazon.com/dp/B0002J226O/ref=cm_sw_r_awd_3ohNub1FXEMV3

I had one in my old car and keep meaning to buy it for my new setup.

Just use a RCA Level Controller on the Sub RCA's. and you effectively have sub remote on any amp you want.

You could get something like the Alpine Power Pack and an universal bass knob that has RCA cables in and out to use as volume control. Then use an RCA to AUX cable for your phone/tablet.

PAC LC-1 Remote Knob - $10.84

http://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O

Works with every amplifier, possibly the best purchase I've made in my setup. Simply controls the signal running from the head unit to the amplifier, therefore controlling the volume of the amp.

Conventional "bass" knobs could possibly blow your subs like my sister did. She had a system installed and the installers mounted the "bass" (gain) knob on the dash and told her to control it for how much bass she wanted. She blew them within a year to the point the one seized and I couldn't punch it free...

I think he meant a headphone amp/dac, which often have preouts to control the volume of your speakers. Schitt Fulla 2 is one example.

This things $10 and should work fine, albeit being a bit small.

Something like this, link courtesy of another poster upthread a ways. Put it after the preamp.

A kludgey solution for a bad situation ... I suspect those speakers are only intended for use with that DVD player which did have a volume control (and Coby stuff, sorry to say, is all crap).

Will adding this level adjuster after my phono preamp and in front of my powered speakers affect quality? I plan on adding it to my chain because each powered speaker (KRK Rokits) have their own volume control on the back of each unit which is a nuisance.

Thanks

clinometer

Removed the radio and capped it with abs plastic, fit it with a usb charger and [four of these switches in different colors] (https://www.amazon.com/gp/product/B001GH1PU0/ref=oh_aui_search_detailpage?ie=UTF8&psc=1) using these housings

the switches got to [relays] (https://www.amazon.com/gp/product/B017VDI0GY/ref=oh_aui_search_detailpage?ie=UTF8&psc=1) that are powered [by this fuse box] (https://www.amazon.com/gp/product/B00QMTAZ1W/ref=oh_aui_search_detailpage?ie=UTF8&psc=1) that is mounted to the top of the OEM fuse box under the hood.

Those power my OBHS and OBA. Other two switches not in use yet, hoping for rock lights/light bar some day maybe?

Removed the old fog light switch panel, replaced with abs plastic and volume control that goes to an amp that goes to a stereo jack that i just plug into my phone for music.

Get a bass knob. I put mine in and love the ability to change it depending on the song or music type

(Man, this turned out a long longer than I thought it would, for relatively little content. I guess I just have a lot of feelings about audio equipment.)

I'd really recommend reading a bunch of reviews and auditioning what you can (I know that's not always practical, I sure bought mine without listening to many alternatives).

I really like the noaudiophile.com guy's reviews, though I know there are people that disagree with some of his conclusions and methods.

/r/Zeos also has a shortlist and some mini-reviews of both powered monitors and bookshelf speakers + amps, and where our experience overlaps I agree with them, so I imagine my advice in that price range would match theirs. (Though after a quick look, it seems some of them are a little out of date, with links to discontinued equipment.)

If you're willing to spend that much, I can't recommend enough making sure your speakers are properly positioned with stands (you don't have to spend much though: the noaudiophile guy uses soup cans to prop up speakers he reviews at his computer!). You may also consider rubber isolation mats.

I personally use—and very much enjoy—the JBL LSR305s, which I got for 280$ a pair, but they're usually 300$ (typically sold by the each at 150$). When I searched for that price, I found out they've just been replaced with the "305p MkII", but changes are minor and all improvements.

Studio monitors are popular for audiophile grade computer speakers because they're designed for near-field, critical listening, unlike typical bookshelf speakers.

On the other hand, they're designed for a very linear, uncolored sound. Speakers can essentially be thought of as a musical instrument, and while there are plenty of wrong ways to make them, there's no one right way. Precision is just one basis for judgment (though the one I find most soothing to go by, since it's easiest to measure).

The LSR305s specifically have been very popular on /r/audiophile, but there's also a lot of praise for the ~400$/pair Yamaha HS5s and AudioEngine A5s. I personally wouldn't bet a lot of money that I'd be able to tell a big difference between my speakers and those higher priced ones.

**

The rest of this post is just advice for if you do get a Studio Monitor. Many (including the JBLs and the Yamahas I mentioned) aren't terribly user friendly. I ran into some stumbling blocks, so I'll mention them here. They're designed to be stand-alone, giving flexibility to your recording engineer, so to run them in stereo, you'll need a way to control the volume of them together (not to mention some unusual cables/adapters, and space to plug in two things on your power strip).

Zeos recommends this line level control, which is only 10$. There's also a "passive preamp" by Nobsound on Amazon for 40$. I don't think you can do too much to mess up a stereo potentiometer with modern manufacturing, so the extra money for the nobsound one is probably just for the nice box and connectors (admittedly, I built my own passive pre-amp and spent probably too much on a stepped attenuator for it).

Obviously, you could instead control volume directly from your computer's volume control, but there's a hidden hazard there, so this is secretly the more expensive option. On nearly every computer, the built in digital-to-analog-converter (DAC) is 16-bits; turning down the volume digitally fundamentally means cutting the audio resolution your computer outputs. The way around this is a 24-bit DAC: almost all audio is recorded/produced at 16-bit resolution (it's the CD standard; but also, about the limit of detail a human can hear), so you can go to .25% volume on the computer before you touch the real data. My recommendation is the Objective Labs DAC (99$).

Some people recommend a dedicated, high quality DAC anyways for a sound system around a price point like 500$. I do own the ODAC (predecessor to the OL DAC), but for me it's almost just for peace of mind.

As a cable example: if you get JBLs and a volume control, you'll need this for computer to volume control and a pair of these for control to speakers. (Not recommendations, just top results on amazon for those types.)

PS: One thing you don't* have to worry about at all is "balanced". Most studio monitors can be run balanced, but they'll also run unbalanced just fine. You'd need a very expensive balanced DAC to make use of it, and assuming your home is not the maelstrom of EM interference a recording studio is, it just isn't necessary (it's not even "overkill", if you don't need it, balanced equipment just adds more components that could produce interference).

^(edited to correct first cable link)

Get an inline rca controller like this one : PAC LC-1 Remote Amplifier Level Controller https://www.amazon.com/dp/B0002J226O/ref=cm_sw_r_awd_iFqcvb00B2SD3

The simplest way is to get a passive volume control, like this one, or a higher end one, like the mackie big knob passive. I have that one and like it a lot.

A better way is a dac/amp combo like the fiio k3, schiit fulla 2, etc.

You plug the speakers into the dac output using the correct cable, set the physical volume on your speakers (I usually go around 75%) and use the volume knob on the dac/amp to adjust while listening. And being that you're using the dac instead of onboard sound, you'll probably get less noise and interference.

http://www.amazon.com/dp/B0002J226O

so between the denon and the emotiva

If you are missing an optical optical cable those can be had for like 6$

https://www.amazon.com/gp/product/B00NH11H38

RCA Volume control:
https://www.amazon.com/dp/B0002J226O
(made to be mounted under desk or car dash, lable upside down on top of desk)
 
If talking purely SPDIF/Optical vs USB, optical cannot have noise caused by electrical interference of other circuits. However the DAC chip used and the circuit design on the DAC plays a factor as well. If a device has poor circuit design the power delivery could be degrading, or interference between its own left and right channels could happen.

I have no experience or knowledge of the Fiio D3, it would work but I can't tell you how well, but I would say I personally would put more down on something that feeds into a pair of 305.
 
A Micca Origen+ would work but its just the same as a DAC X6 basically.

https://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O/ref=sr_1_2?ie=UTF8&qid=1520984402&sr=8-2&keywords=stereo+volume+control

You'll need a headphone amp with preouts, a more traditional preamp, or a level controller. Schiit Magni 2 Uber or Audioengine D1, for the former. Control Freak or something like this for the latter. Or the Schiit Sys.

In my garage, I run a chromecast hooked up to this guy running a pair of 8" speakers from the 80s. :https://www.amazon.com/gp/product/B077Z7DBRT It's 20w and powers them just fine for the whole 2-car garage. I'm not recommending that for high volume, but it does the job. A used receiver would work really well too, they're just much larger.

​

You can get a pretty simple RCA pot volume control knob on amazon that you could use for the sub. https://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O/

You have several options:

1. Easy, cheapest, move on with your life
   Buy the cable sociojeje linked (or whatever one you want as long as it goes from one 3.5mm to dual mono 1/4 inch). Plug 3.5mm into soundcard/onboard audio and 1/4 inch into the inputs on each speaker. Since you want to leave the volume control on the back of the monitors in one position and never touch it again, with this setup you will be using your PC for volume control, which usually sucks.
   
   2)I want to control volume outside of windows approach
   Get an inline volume control (https://www.amazon.ca/dp/B0002J226O/?coliid=I21HE0GYZHPUID&colid=1VYF10R99G2UC&psc=0&ref_=lv_ov_lig_dp_it is the cheapest one I can find). You get a 3.5mm to dual rca cable from your pc to the input on the volume control, then two rca to 1/4" from the control to the monitors. Leave windows at like 75-100% volume (you are going to have to experiment) and use the volume knob on the inline to control volume. This is also the ideal solution if you have an external DAC or buy one at some point (which you should)
   
   3)I want all the things, but dont want to spend a lot of money
   Buy this: https://www.amazon.ca/Micca-OriGen-G2-Resolution-Preamplifier/dp/B01N14SY65/ref=sr_1_2?ie=UTF8&qid=1540965426&sr=8-2&keywords=micca+origen+g2
   
   This an external DAC AND headphone amplifier in one. What makes this one special, is that you can switch between headphone out and line out (speaker) with the toggle switch at the front. This will replace your soundcard once its plugged in by USB and will also serve as your volume control. If you have headphones, it would be plugged into this as well. Cable wise, it would be USB from PC to the Dac (included with unit), then two RCA to 1/4" mono cables from the dac/headphone amp to the speakers

What you're looking for is an audio interface. Like /u/ANeedForUsername said, the 2i2 is very popular. I use a 2i4 myself to drive my JBL LSR305's and the sound is amazing. The scarlett has a high quality DAC, so it will deliver a better sound to both your headphones, as the JBL's.
It also enables you to use balanced cables for your 305P's, which should eliminate electrical interference. Highly recommended but it can be expensive.

If this is too expensive right now, you could go with a simple inline control for the volume control of your monitors and any 3.5mm extension cable for your headphones, plugged into the audio output of the back of your computer and attached to your desk/whatever suits you. But you'll have to switch between manually between output on your computer. This is what I did to connect my headphones before I got my Focusrite.

EDIT: The Behringer U-Phoria UMC202HD Could also be a cheap alternative, although it will be of a noticeable worse quality compared to the Focus rite.

I bought this to do volume control PAC LC-1 Remote Amplifier Level Controller https://www.amazon.com/dp/B0002J226O/ref=cm_sw_r_cp_api_Iy0ZBbXAAZ5JG I actually attached it to the back so my kids wouldn't mess with the volume but it's great i turned it to the max then adjusted the amp to a level I thought was the threshold of loudness.

Looks cheap because it is. It'll work just fine.

I think one of the issues I ran into was when I had speakers connected to the subwoofer - I had no way to control the volume. besides the tiny knob on the back - which is very annoying to have to reach for every time the mood strike. It does not seem like I have an option for one of these either. Would one of these fix that? Would this control the sub and any speakers running through the sub?

The way it is now - when i turn down the volume on the receive all the speakers turn down with it - but the sub is on its own control

I wish I could use something this somehow?

Any headphone amp can do the job if you have one. Otherwise the Schiit sys has nice aesthetics: https://www.amazon.com/Schiit-Audio-SCH-13-Passive-Preamp/dp/B00K6Q2A4C/ref=sr_1_1?ie=UTF8&qid=1474215582&sr=8-1&keywords=passive+volume+control but a passive volume control such as this will work: https://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O/ref=sr_1_3?ie=UTF8&qid=1474215582&sr=8-3&keywords=passive+volume+control

Sound quality with monitors is going to be leaps and bounds better than the other two, even if they're close together.

like this?
http://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O

I have L,R coming out of the amp, into a female 3.5mm jack.. Then I have Male 3.5mm to L,R Male going into the cable box.. Where would this plug in with my setup?

also, what about this? http://www.earphonesolutions.com/leatwivoco.html Any other cheap things like that around?

Found these two as well: not sure witch one i should go with though :/

http://www.volutone.com/CALRAD-10-105-STEREO-INLINE-LINE-LEVEL-AUDIO-ATTENUATOR-P8778.aspx

http://www.calradstore.com/10-105.html

There are two good ways to do this:
Option 1:
Grab yourself a set of these. https://www.amazon.com/CableWholesales-Audio-Piggyback-Cable-Female/dp/B000I94FAE/
Plug the double sided end into your source, and then feed the other end to your speakers. You'll then plug another set of RCA into the open ends on the source and send them to your Sub.
Option 2: If you don't like using the windows volume control, then you'll get one of these: https://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O/
Also this: https://www.amazon.com/Link-BM105-Male-Barrel-Connectors/dp/B001NCDBEQ
The Barrel connectors will go into your source. Then plus the controller into the barrel connectors, then the piggyback cable into the other end of the controller. Then plug your RCA into backside of the Piggyback and put one set into the speakers, and one set into the sub.
Once you've chosen from the two options, you'll need to set up the speaker and the sub so the volume matches.
To do that I would turn the computer audio up to maximum. Then, turn your speakers up as loud as you would ever comfortably listen to them. Then get your subwoofer gain and crossover where you want it. You will then use your PC volume/or the control nob to control the volume of both of them. If you use the control nob, your PC volume will always be at max.
EDIT: You might also need this to get the sound from your motherboard audio out to RCA: https://www.amazon.com/Monoprice-105597-3-Feet-Premium-Stereo/dp/B0094A1F3S/

Something like this would work https://amzn.com/B0002J226O

There are a bunch that look like this. MCM Electronics also sells a version on their site for under $40 that has an IR remote, so you can add it to any living room setup no matter if they are powered monitors, integrated amp, power amp, anything.

So when I bought mine I ordered one of these amplifier controller thingies. I have it connected between my DAC and the 305's. It works well enough but I've found it more convenient just to adjust the volume in Windows. I have the actual volume on the back of each monitor set to "5" to prevent me from easily maxing out the volume in windows. With the volume at 5 these are plenty loud enough for a desk.

You had the right idea with the line level controller. I personally don't hear a difference between in sound quality with using the line level controller and having it disconnected but I know some people are much more critical than I am.

Good luck with your setup!

I don't understand the exact way your speakers are connected but you can buy RCA with bass control (this is actually made for car audio but should work) https://www.amazon.com/gp/aw/d/B0002J226O/ref=mp_s_a_1_1?ie=UTF8&qid=1501485062&sr=8-1&pi=AC_SX236_SY340_FMwebp_QL65&keywords=rca+with+knob&dpPl=1&dpID=41ZmLlVIp0L&ref=plSrch

Thank you for the comments. The second one shows the installation of a potentiometer using one of the speaker leads, which seems to be a good way to externally mount the Pandora Box 6 volume control (instead of having to open the cabinet to adjust the wheel on the actual device). However, I think the leads to the potentiometer would need to be extended to allow it to cleanly mount to the outside of the cabinet.

The first video shows a solution designed to work with something more customizable, like a Raspberry Pi. I just like how professional it looks. The downside is that you have to drill the holes perfectly since at least two of the holes won't be covered by any trim (the amp controls go right through the holes).

The fact that the speaker and power switch can connect directly to the Pandora's Box were big pluses for me. However, from what I read, it seems like different games have different volume levels so I do think having an external volume control is a good idea. The more I read, the more I think I may go with a Raspberry Pi according to ETA Prime's tutorial, deal with the script edits necessary to get the power button to work semi-correctly (seems to just allow the RP to shut down but the amp stays on) and use some of the ideas from the first video I posted. It just seems to allow for the cleanest design with most flexibility going forward.

I guess the ideal solution would be Raspberry Pi + a cheap amp that has a clean externally mounted volume control. Maybe something like this https://www.amazon.com/d/Car-Audio-Video-Remote-Controls/PAC-LC-1-Remote-Amplifier-Controller/B0002J226O/ref=sr_1_3?ie=UTF8&qid=1550113401&sr=8-3&keywords=amp+volume+control ?

Worst case you can go old school and patch in a line level attenuator. Both fixed and variable are available. Here is a variable one https://www.amazon.com/gp/aw/d/B0002J226O/ref=pd_aw_sim_23_3?ie=UTF8&psc=1&refRID=EA44EP0EKJSY5YT72D5G&dpPl=1&dpID=51Nlba1-fGL

Fellow Airmotiv user, why no Sys or Control Freak?

The Schiit Magni 2 Uber can be used as a headphone amp and passive preamp for speakers.

Otherwise there is not that much on the market for cheap. You would be looking at something like this

http://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O.

OP didn't respond yet so I'll help out with my setup. Scarlett 2i4 as interface between PC and speakers. Looks like OP is using a PAC LC-2 to merge the sub with the powered speakers.

Set speaker volumes to 6.5 to cut some of the hiss as this is a very near-field setup for me. Others have had success at different volumes on the speakers but most do turn them down from wide open...

I’ll try that out in a few minutes when I get home!

this is the current level controller I bought

but I bought this one today to work with the chrome cast audio I bought as well

I believe the green rimmed ones are at Amazon for the same price: https://www.amazon.com/gp/product/B00KVEIY4E/

If I can recommend, get a line level controller so you can turn the volume up and down independent of your computer (https://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O/)

Nah, you just split your rcas or 3.5mm but then you have to rely on pc volume control OR add a line level controller.

Can do Cheapo like

https://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O

https://www.amazon.com/dp/B0002J226O/ (cheap)

https://www.amazon.com/dp/B0058B1T4M/ (med)

https://www.amazon.com/dp/B00WT4DJN0/ (expensive, what I use to have)

Ooh even better! Would something dirt cheap like this little guy or this tiny thing be alright? I'm a broke college kid with JBL LSR305s and a cheap JBL sub. I would get two: one for the 305s and one for the sub.

I'll probably have to get them to install a new one anyways guess I'll have to drive without bass for little while. :/ This is the knob itself http://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O

That looks good, but what about this for a budget solution?

PAC LC-1 Remote Amplifier Level Controller https://www.amazon.com/dp/B0002J226O/ref=cm_sw_r_cp_api_I7U3ybWM3XDYZ

Yes.

https://www.amazon.com/MCM-CUSTOM-50-8394-CONTROL-REMOTE/dp/B01CX82KH2

Although a knob on wires is cheaper:

https://www.amazon.com/gp/aw/d/B0002J226O/

There's also the DIY case option:

http://m.ebay.com/itm/9V-Infrared-Remote-Control-Volume-Control-Board-ALPS-Pre-AMP-Motor-Potentiometer-/322328825653

Yes, any decent amp should come with the remote gain knob (shitty amps come with bass boost knob, which you absolutely do not want to use), if it doesn't just pick up a PAC-LC1 for $10-15. Lots of people running very high end gear run those, it's especially helpful for controlling multiple amps at once since it attenuates the input signal.

Remote RCA Level Controller https://www.amazon.com/dp/B003FPD3IS/ or
PAC LC-1 Remote Amplifier Level Controller https://www.amazon.com/dp/B0002J226O/

You will also probably need another short male to male RCA cable. Or Male to Male Barrel Connectors https://www.amazon.com/dp/B001NCDBEQ/

If you don't have measuring equipment or some resistors handy, an easy way to confirm too much output signal is by putting the Kenwood (or another pre-amp or pre-amp section of an integrated amplifier) between the new pre-amp and the computer, via the Kenwood's line-in instead of its phono in.

Or borrow a passive volume knob (or "bass control knob" in car audio) such as:

https://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O/

I have one of these for an old subwoofer setup, something like this should work well for your needs :)

https://www.amazon.com/dp/B0002J226O/ref=cm_sw_r_cp_apa_cTEYBb803GKAW

cool, thanks for the link!.. That appears to be the only thing of its kind available on the web.. Do you know what would be the appropriate configuration (mono/stereo, pot value) for something like the Kemper? And is that knob not the same thing as, say, this?

You got a great deal on that amp then.

Without a gain adjustment, I would be very cautious to do this. Even with something like the Fulla it would be easy to blow out your speakers if you turn the dial too high. You could use this to limit it https://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O but you need to be very careful.

Personally, I would sell that amp and pick up an SMSL SA-60. The amplifier you have is meant for a very different purpose than you are using it for and the chances of you blowing up your speakers is too high.

sorry miss read. thought you I read r1850db.

It is a bit complicated. What you need to do is split the input signal that you are getting form the RCA, One set to the R1280DB master, and one set will go to the sub. If you want simpler volume control for the sub. Get a RCA gain knob, and put it inline to the sub.

https://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O/ref=sr_1_1?keywords=Bass+Remote+Level+Volume+Control+Knob+Stereo+RCA+Input%26Output&qid=1568415904&s=gateway&sr=8-1

But this will not work for optical. With optical. You have the issue of stereo bass. You would run the speaker cable to the a sub that has high level input. The run the speaker wire form the high level output to the slave speaker. But you wont get bass in stereo. Only bass form the slave will be played.

That turntable has a pre-amp. Why did you buy a separate one?

For controlling volume, I think you would need an inline volume control in between your pre-amp and the amp. Something like this: https://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O/ref=sr_1_1?ie=UTF8&qid=1474060319&sr=8-1&keywords=line+level+volume+control

However, note that those can only REDUCE the volume...so if the amp isn't loud enough to begin with, I'm not sure what your options are.

It has 2x 10a fuses. Following ohms laws: Amps volts = Watts. So 20 14.4 = 288 watts. So the absolute max your amp could put out is 288 watts. The fuses are there to protect something from getting to many amps and fire/melting/over powering. The amp I linked will give your subs the power they need whether you have D2 or D4 version. Also remote bass knobs are not universal. But would you could do is get one of [these] (http://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O) which is the best type of knob you can get because it control RCA voltage instead of Bass boost (which the Hifonics is). And you wire this one but just putting it in between your RCA from your amp. It has a input (from headunit RCA) and output (to amp RCA).

Maybe something like this? http://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O

That does seem like quite a mismatch! I'm hoping that's what the problem is. Do you reckon something like this would effectively attenuate the signal for what I'm trying to do?
https://www.amazon.com/dp/B0002J226O/ref=cm_sw_r_cp_apa_htUqxbXK3BKYZ

My powerful yet stealthy touch screen sound system for about $500: An Amazon kindle running the Pandora app sits in a kitchen cabinet. Plugged into the audio out is a headphone to RCA adapter. That's plugged into a passive volume control mounted beneath the cabinet. The output drops down to the basement, where I have a signal detecting power amplifier. That amp drives four Polk in-ceiling speakers mounted in our open concept first floor.

you need gain control.

https://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O/

https://www.amazon.com/Axxess-AALC-Controller-Discontinued-Manufacturer/dp/B003FPD3IS/

between the player and the amp.

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you can add attention between the amp and the speakers too.

I have the 793II, headphones and powered monitors and one thing you will want to have is a line level controller like this [one] (https://www.amazon.com/PAC-LC-1-Remote-Amplifier-Controller/dp/B0002J226O?ie=UTF8&keywords=line%20level%20controller&linkCode=sl1&linkId=a51154bf02562557a1228b2f373428ac&qid=1444319538&ref_=as_li_ss_tl&sr=8-2&tag=wwwpuresimula-20) as the 793II has a line out not a pre out. This way you don't have to change your computer's volume when you want to change your powered monitors volume.
I am still an audio Padawan, but the SMSL Sanskrit DAC with a FiiO K5 AMP seem to fit what you need, others will have to comment on sound quality as I don't have any experience with them.

Yes, avoid +db on any part of your signal path, be it a head unit setting or bass boost knob.

Set gains to maximize clean output, then use something like an RCA cable volume knob to dial down your sub to taste.