What did you set your gain at?

 

next time I pull the outer I'll check...how do you measure voltage? I have a basic meter.

 

The Kappas can (and will) handle most any voltage a sane person can throw at them as long as the power is clean. If you're going to start with DMM tuning, you can safely set the voltage to 23.71v using a clean 1kHz .wav test tone (I get mine from JL and drop it onto a USB drive). That yields 225W, which also happens to be the peak RMS rating of those speakers. All music is dynamic to one extent or another, source amplification, bit rate, signal to noise ratio and even EQ settings all come into play at some point. The most I can tell your from 4 years of experience with Kappas and the CV 2-channel stealth AMPs is that mine have been set at 23.71V as a starting point and then fine tuned from there. I have blown exactly Zero kappas in that time and going on 25K between my 2015 and 2018 RGS bikes. My radio is always turned up just loud enough to hear it depending on the riding environment / conditions.

 

This is all fine and good but there's no way I'd recommend this to a novice that is unsure of what he's doing to begin with. This will cause magic smoke to occur quick, fast, and in a hurry.

 

In my OP I mention setting the gain by ear then checking the voltage which turned out to be 25. I got scared and turned it down to 18. I did find a post where someone with the same setup was running 25 volts though. I still need to turn up the volume past 2/3 to hear clearly at highway speeds so I may try 20 volts at 2/3 instead of 18. Don't know what the difference is between a novice and a pro when using a DMM to set gains with a 1Khz test tone? Seems pretty straight forward to me. My confusion started with the sticky which says use amp output and speaker impedance to calculate gain and people who said to use speaker rms rating and impedance instead (and peak power handling now in the latest reply) https://m.youtube.com/watch?feature=...n0llYqM8w#menu If the latter is true then the sticky needs to be corrected, wouldn't you think?

Jim

 

I'll just throw in that Ohms law is just that, law. If you can detect voltage and you know your resistance you can calculate your wattage dissipated by squaring voltage and dividing by the resistance (P=V³xR).

Also if you know what the amp is truly capable of at your resistive load (speaker impedance) then you can multiply the wattage times the resistance and then take the square root of that to see what your voltage should be set at. I think this is what a lot of folks do when setting with a volt meter. It does however hinge on having the true wattage capability of the amp available. If your amp came with a test sheet like Rockfords do or if you know someone has benchmarked your amp in one of the stickies you might could use that value. If it seems too loud too quick you could back it off a volt or two but folks here have had good results with the square root of P x R calculation.

 

 

Jim, I didn't get involved in bike audio until I got my first Road Glide back in 2015. Before that I was on a wide glide, and before that I was on various KW sport bikes. So while I've been around this particular forum since '11, I've only been interested in bike audio since mid '15. In those three years, the knowledge about audio as it applies to the touring bikes has grown exponentially around here. Prior to this my only other audio experiences came from home and automotive (co-owner of an car audio shop back in the early '80s). I state all that as a disclaimer "I'm not a bike audio pro". No one pays me to do it, I'm not a distributor, reviewer or reseller for anyone etc. There are others around here who have been at it a lot longer either professionally or in practice, so I'm always the first to defer to their expertise.

All I can tell you is based on my own experience. And in this case I've got personal experience with the exact same audio gear you're running. When I initially installed a B2 + Kappa 62.11 speakers in my 2015 I set the gain using the max rated output of the AMP. That was OK, but I was definitely getting some distortion on certain music genres at maximum volume. So I tuned "downward" by ear, put everything together and left it like that............... for a while. While we were selling off some older equipment at our business I came across a couple of o-scopes that we had in our lab. I couldn't resist the temptation, so I toted one home, pulled my fairing back apart and started measuring everything I could (voltages, sine waves and the likes) everything from PAC LOC, BT355, head units 4.3 and later 6.5 and of course the CV B2 and later the B52 AMPS. Later on we bought a hand held o-scope for our lab guys and I got a chance to play with it as well. I've measured the sine wave and power output of one B2 and two B52 AMPs. All three of those were capable of outputting a clean sine wave using a 1kHz test tone up to an average of 27.6v, albeit with no resistors to provide a simulated load on the lines.

However, don't get too hung up on the math and scientific observations. Because as you know, there is signal to noise ratio, RMS rating, speaker sensitivity, frequency range, speaker impedance, quality of components, type of components, distortion etc. that all have an impact on how loud your system sounds and how well your system sounds. In the same time I've been around here I've read about ruined gear, blown speakers, magic smoke and all manner of catastrophic consequences from "inexperienced" installers. And while I'm 100% sure that those horror stories are true, all I can tell you is that (again in my own experience only), I've yet to ruin a set of Kappas except for a single one that I ruined when I forgot to disconnect the leads and turned on the bike with a 1kHz test tone playing at 3/4 radio volume and my AMP outputting about 27v to the speaker. The voice coil melted almost immediately. Yes, I smelled the magic smoke (even saw a puff of it) before I got things turned off. Word of advice..... don't make that mistake

To a person, about everyone experienced with any audio around here will tell you to tune by ear. And that is solid advice. Pick a starting point, whether that is 14v, 18v, 20v or 23.71v and fine tune from there. Setup parameters are important so make sure you've got those down square. There are a couple folks here and over at RG.org who have heard my own personal installation on either my 2015 or 2018. They will tell you that their systems sound a lot better than mine (and they are right), but I don't have a grand or more tied up in mine either. And I'm not knocking anyone that has the passion or resources to spend tons of money on their bike audio. But if I do that, then I have to justify why I won't spend that on the audio in my truck, car or boat All of which my wife spends a lot more time in or on than on the back of my bike.

 

Great post,thank you. By the way I have no idea how that Deuce Bigalow clip ended up in the middle of my post LoL, I did click on it in another thread though...

 

+1 on using an oscilloscope to see what is really going on as wevsspot has said. That will give you a true understanding of what is really happening. If he has tuned similar equipment in that manner then I would count that as a good goal for the OP to work towards.

This week I dug out my old Tenma scope and tuned a line driver for my TM400x4ad that just couldn't keep up with the PN4.1000d under the fairing and got a lot more clean sound out of that amp.