JBL 308P and 708P

[tokenbrit]

Maybe Spannko has a screw loose... :? :D

[Spannko]

Maybe Spannko has a screw loose... :? :D

This is the most likely explanation!

[Lego]

Maybe Spannko has a screw loose... :? :D

This is the most likely explanation!

Don't worry Spannko ,it's treatable 😃

[Lego]

Have you checked settings at the back or could your KDS be a bit ropey ?

[Spannko]

Have you checked settings at the back or could your KDS be a bit ropey ?

There’s a small gain switch. Not sure what it should be on though. I’d have to plug them back in to experiment.

I think the KDS is OK because it makes the LS5/9’s sound pretty musical. I thought it might have a fault after it was thoroughly demolished by a Källa at David Neel’s, but now I’ve got used to the lower performance again it’s OK.

[lejonklou]

Something worth knowing about JBL 308 is that they tie signal ground to mains ground. This can be problematic in some systems, causing hum, radio frequency noise and/or degradation of the music.

For instance, I have Källa - Sagatun Mono - JBL 308 at home. All powered from the same grounded strip with SM first, Källa in the middle and 308 last. Sounds great!

If I would add either my Panasonic TV, a HAKAI or a KDS to this system, I get problems.

The simplest solution to the problems is often to remove the mains ground from both JBL 308's.

[Discodave]

I have my 308s on a completely different power socket and power strip due to necessity. The only other thing on the power strip is a Crosstrainer exercise machine(don't ask!).

It seems grand to me and it is pointless even testing as it won't work in the room and only infuriate me if better. Ignorance is bliss here.

[Spannko]

Something worth knowing about JBL 308 is that they tie signal ground to mains ground. This can be problematic in some systems, causing hum, radio frequency noise and/or degradation of the music.

For instance, I have Källa - Sagatun Mono - JBL 308 at home. All powered from the same grounded strip with SM first, Källa in the middle and 308 last. Sounds great!

If I would add either my Panasonic TV, a HAKAI or a KDS to this system, I get problems.

The simplest solution to the problems is often to remove the mains ground from both JBL 308's.

Ah, maybe the combination with the KDS is not a good one. I’ll try the KDS on another circuit later.

[lejonklou]

On another circuit is not necessarily a good idea. It could be much worse as you would then have a massive ground loop instead of a small one.

What is needed is to remove the mains ground from the JBL 308's.

[Discodave]

On another circuit is not necessarily a good idea. It could be much worse as you would then have a massive ground loop instead of a small one.

What is needed is to remove the mains ground from the JBL 308's.

Would I need to do this and if so how does one go about removing mains grounds from 308s? Thanks

[Discodave]

Forgive my naivety, haven't a clue about this stuff.

[lejonklou]

You need a power cord without ground.

[Spannko]

On another circuit is not necessarily a good idea. It could be much worse as you would then have a massive ground loop instead of a small one.

What is needed is to remove the mains ground from the JBL 308's.

Ah, yes. I didn’t think about that!

[John]

You need a power cord without ground.

Sounds dangerous if the device is intended to be used with the ground.

[Discodave]

You need a power cord without ground.

Thanks

[tokenbrit]

You need a power cord without ground.

Sounds dangerous if the device is intended to be used with the ground.

Potentially...

[lejonklou]

You need a power cord without ground.

Sounds dangerous if the device is intended to be used with the ground.

Yes, having a mains ground is safer. In modern installations it will make a central fuse trip really fast when anything malfunctions. Without a mains ground it will take a little longer.

But I don't have any mains ground in my apartment and I didn't have any in my previous one either. So the mains ground of JBL 308 and other units has no safety function where I live. All they do is connect to each other through the power strip and this is good for the music, as it keeps all chassis potentials the same, but problematic when some units tie the signal ground to it and others don't.

[Defender]

dangerous? on a plastic/wooden housing
@Spannko: settings are -10dB and the rest HF at 0dB and LF at 0dB but can vary in your room
especcially the LF setting

yes for sure saver with but low risk in this case the only metal you can touch is the line in and line out xlrs

[John]

dangerous? on a plastic/wooden housing
@Spannko: settings are -10dB and the rest HF at 0dB and LF at 0dB but can vary in your room
especcially the LF setting

Dangerous for any other device connected to them?

[Defender]

is the construction of the stands key for performance or more the hight?

[jajo]

is the construction of the stands key for performance or more the hight?

Hard to say what is most important but clearly both are important.

We have limited experience from using different stands with these speakers but Kan and Katan are known to work well.

[Discodave]

You need a power cord without ground.

Sounds dangerous if the device is intended to be used with the ground.

Yes, having a mains ground is safer. In modern installations it will make a central fuse trip really fast when anything malfunctions. Without a mains ground it will take a little longer.

But I don't have any mains ground in my apartment and I didn't have any in my previous one either. So the mains ground of JBL 308 and other units has no safety function where I live. All they do is connect to each other through the power strip and this is good for the music, as it keeps all chassis potentials the same, but problematic when some units tie the signal ground to it and others don't.

Aha, think I'll leave it!!

[Discodave]

is the construction of the stands key for performance or more the hight?

Hard to say what is most important but clearly both are important.

We have limited experience from using different stands with these speakers but Kan and Katan are known to work well.

For interest sakes.... I have placed my 308s on 109 stands with Skeets. Top to bottom = 60cm. I'm quite content with this.

[FairPlayMotty]

Atacama Nexus 6 with my 308s. 60.5cm.

305s arrived, working perfectly and making me smile :)

[Azazello]

You need a power cord without ground.

Sounds dangerous if the device is intended to be used with the ground.

Yes, having a mains ground is safer. In modern installations it will make a central fuse trip really fast when anything malfunctions. Without a mains ground it will take a little longer.

But I don't have any mains ground in my apartment and I didn't have any in my previous one either. So the mains ground of JBL 308 and other units has no safety function where I live. All they do is connect to each other through the power strip and this is good for the music, as it keeps all chassis potentials the same, but problematic when some units tie the signal ground to it and others don't.

Would it be generally beneficial to cut the ground cord in the power strip..?