I seriously love my K1600GTL. But I have never loved the audio system. I refused to spend $2200 to get the full Bluetooth experience from BMW including two helmets that didn't fit. I've struggled with the Cardo G4 (pretty bad) and the Sena SMH10 (much better) but I was always annoyed that my passenger was prevented from listening to the audio system and that the wonder wheel didn't control the volume if I wanted to use Bluetooth. I was also annoyed by the lack of input level control that caused distortion on FM and Sat Radio and a barely audible Nav when using Bluetooth.
I did install a couple of 3.5mm jacks so I could connect the SMH10s via wire. That works well and solves all of the above issues. Well it doesn't give individual input level control, but the default levels to the speakers are much better than the Bluetooth, so isn't nearly the same issue.
The problem is the wires. I really wanted to go Bluetooth the way I felt BMW should have given me from the start. Now I've got it!
The new SM10 from Sena gives me exactly what I was looking for from the beginning. My total investment to make things the way they should be is right around $500 including the two SMH10's and the SM10, a power source, a ground loop isolator and all cables and connectors.
I should mention that I am no audiophile. Bluetooth compression definitely flattens out music, but that is true regardless of the headset. I can live without wired quality at highway speeds. My ears can't tell the difference anyway. And if I wanted to get the highest quality I could out of the Bluetooth, I'd go with ear buds on the SMH10's instead of helmet speakers. In any event, the sound quality from the SM10 sounds as good as or better than the K1600 Bluetooth to me, so I've lost nothing there.
Most of this has been covered elsewhere, but for those new to the forum who want to get a Bluetooth system going that works for both the rider and the pillion and is fully controllable from the wonder wheel, here is what I did.
The idea is to tap into the bike's speaker wires to get the audio to the SM10. If you've already installed a 3.5mm jack, the SM10 is pretty much just plug and play. But I'm assuming starting from scratch. With that in mind here is what you need:
1. 2 X Sena SMH10 headsets. Sena says you can use most any headset with the SM10, but the SMH10s are as good as it gets, IMHO and we know they work great with the SM10.
2. 1 X Sena SM10
If you don't power the SM10 off the bike and you intend to only use it powered by its own battery that you will have to charge, you can skip the isolator in #3. Otherwise:
3. You will need a way to block ground loops since you will be powering the SM10 and the Alpine stereo from different sources. Many here have used either the Autocom 3.5mm Stereo Isolation Lead, or the Autocom Factory-type Stereo Music Lead with Toggle Switch . You will likely want a switch in this application, more on that shortly.
My problem with the Autocom choices is that they are way too expensive and the level reduction is not adjustable. You need to reduce the power level coming off the speaker wires you are going to tap as the level is too hot for anything other than speakers. The Autocom isolators will reduce the level, but they aren't adjustable so you are stuck with whatever level they give you. Also, the switch on the 2275 is a cheap piece of..., well it just ain't much. Particularly given how much extra it costs.
I went with the PAC SNI-35 Adjustable 2 channel line out converter For $14.35 on Amazon you get the ground loop block you need and adjustable levels for each channel. I get zero engine noise through this, which is the goal.
Whatever you use, this is the device that you will tap into the speaker wires. The SM10 goes on the output side of this device.
4. Assuming you didn't get the Autocom 2275, you probably want a toggle switch to shut off the speakers while you are using Bluetooth. Bluetooth requires compression and decompression, which takes time. The result is the speakers will be out of synch with your headsets. That won't sound too great. You will need a DPST switch if you want a simple on/off for both speakers, or DPDT if you want a center "mute" position. I picked up a black nylon rocker switch at the Shack for about $3 that I mounted above the audio system buttons on the left panel. It matches perfectly and looks like it belongs there to me. An alternative is to just cut the wires going to the speakers and be done with them if you don't think you will ever use them.
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5. You need to power the SM10 if you don't want to take it out to charge. I found it easiest to just get a powerlet adapter to go from the powerlet outlet under the passenger with 24" of cable ending in a cigarette lighter adapter I put under the seat. The SM10 power cable can plug into that. Simple switched power. 24" Powerlet To Cigarette Socket Cable
6. You will need to get the appropriate cables to get from your ground loop block/isolator to the 3.5mm female input on the SM10. The Autocom isolators include a 3.5mm male. I used an RCA to 3.5mm adapter for my PAC SN-35.
![Image]()
![Image]()
Stereo 3.5mm Male to RCA cable
7. You will be tapping into the speaker wires to get your signal. Posi-taps are very popular. I'm a solder and shrink tube guy myself, but posi-taps and posi-twists will work just fine.
![Image]()
Posi-tap Connectors.
This post gives you photos of the wires you will be tapping and this one gives you the color coding.
I found that with two helmets connected I was getting some drop outs on the SMH10s. That problem was solved by disabling "High Quality A2DP" using the SMH10 manager software. My ears cannot detect any difference in the sound quality but the drop outs are gone.
Also, you should reset your SMH10's to factory default settings prior to syncing up to the SM10 if you previously were paired to the K1600. It's probably a good idea to delete all the pairings on the K1600 since you won't be using them anymore. I didn't do either at first and it caused me some initial pairing problems and resulted in my SMH10 turning itself off when I inadvertently turned on the bike's Bluetooth.
With all of that assembled, you will have what we all should have gotten from the start, IMHO. That is an easy to use Bluetooth connection to rider and passenger for all of the audio system with full control from the wonder wheel, and without any requirement for a specific helmet or the need for turning things on in a specific order, saying magic words, swinging a dead chicken over your head or anything like that. It just works.
I did install a couple of 3.5mm jacks so I could connect the SMH10s via wire. That works well and solves all of the above issues. Well it doesn't give individual input level control, but the default levels to the speakers are much better than the Bluetooth, so isn't nearly the same issue.
The problem is the wires. I really wanted to go Bluetooth the way I felt BMW should have given me from the start. Now I've got it!
The new SM10 from Sena gives me exactly what I was looking for from the beginning. My total investment to make things the way they should be is right around $500 including the two SMH10's and the SM10, a power source, a ground loop isolator and all cables and connectors.
I should mention that I am no audiophile. Bluetooth compression definitely flattens out music, but that is true regardless of the headset. I can live without wired quality at highway speeds. My ears can't tell the difference anyway. And if I wanted to get the highest quality I could out of the Bluetooth, I'd go with ear buds on the SMH10's instead of helmet speakers. In any event, the sound quality from the SM10 sounds as good as or better than the K1600 Bluetooth to me, so I've lost nothing there.
Most of this has been covered elsewhere, but for those new to the forum who want to get a Bluetooth system going that works for both the rider and the pillion and is fully controllable from the wonder wheel, here is what I did.
The idea is to tap into the bike's speaker wires to get the audio to the SM10. If you've already installed a 3.5mm jack, the SM10 is pretty much just plug and play. But I'm assuming starting from scratch. With that in mind here is what you need:
1. 2 X Sena SMH10 headsets. Sena says you can use most any headset with the SM10, but the SMH10s are as good as it gets, IMHO and we know they work great with the SM10.
2. 1 X Sena SM10
If you don't power the SM10 off the bike and you intend to only use it powered by its own battery that you will have to charge, you can skip the isolator in #3. Otherwise:
3. You will need a way to block ground loops since you will be powering the SM10 and the Alpine stereo from different sources. Many here have used either the Autocom 3.5mm Stereo Isolation Lead, or the Autocom Factory-type Stereo Music Lead with Toggle Switch . You will likely want a switch in this application, more on that shortly.
My problem with the Autocom choices is that they are way too expensive and the level reduction is not adjustable. You need to reduce the power level coming off the speaker wires you are going to tap as the level is too hot for anything other than speakers. The Autocom isolators will reduce the level, but they aren't adjustable so you are stuck with whatever level they give you. Also, the switch on the 2275 is a cheap piece of..., well it just ain't much. Particularly given how much extra it costs.
I went with the PAC SNI-35 Adjustable 2 channel line out converter For $14.35 on Amazon you get the ground loop block you need and adjustable levels for each channel. I get zero engine noise through this, which is the goal.
Whatever you use, this is the device that you will tap into the speaker wires. The SM10 goes on the output side of this device.
4. Assuming you didn't get the Autocom 2275, you probably want a toggle switch to shut off the speakers while you are using Bluetooth. Bluetooth requires compression and decompression, which takes time. The result is the speakers will be out of synch with your headsets. That won't sound too great. You will need a DPST switch if you want a simple on/off for both speakers, or DPDT if you want a center "mute" position. I picked up a black nylon rocker switch at the Shack for about $3 that I mounted above the audio system buttons on the left panel. It matches perfectly and looks like it belongs there to me. An alternative is to just cut the wires going to the speakers and be done with them if you don't think you will ever use them.
5. You need to power the SM10 if you don't want to take it out to charge. I found it easiest to just get a powerlet adapter to go from the powerlet outlet under the passenger with 24" of cable ending in a cigarette lighter adapter I put under the seat. The SM10 power cable can plug into that. Simple switched power. 24" Powerlet To Cigarette Socket Cable
6. You will need to get the appropriate cables to get from your ground loop block/isolator to the 3.5mm female input on the SM10. The Autocom isolators include a 3.5mm male. I used an RCA to 3.5mm adapter for my PAC SN-35.
7. You will be tapping into the speaker wires to get your signal. Posi-taps are very popular. I'm a solder and shrink tube guy myself, but posi-taps and posi-twists will work just fine.
This post gives you photos of the wires you will be tapping and this one gives you the color coding.
I found that with two helmets connected I was getting some drop outs on the SMH10s. That problem was solved by disabling "High Quality A2DP" using the SMH10 manager software. My ears cannot detect any difference in the sound quality but the drop outs are gone.
Also, you should reset your SMH10's to factory default settings prior to syncing up to the SM10 if you previously were paired to the K1600. It's probably a good idea to delete all the pairings on the K1600 since you won't be using them anymore. I didn't do either at first and it caused me some initial pairing problems and resulted in my SMH10 turning itself off when I inadvertently turned on the bike's Bluetooth.
With all of that assembled, you will have what we all should have gotten from the start, IMHO. That is an easy to use Bluetooth connection to rider and passenger for all of the audio system with full control from the wonder wheel, and without any requirement for a specific helmet or the need for turning things on in a specific order, saying magic words, swinging a dead chicken over your head or anything like that. It just works.
