Panasonic ub820 player audio issues

Drooch

Active Member
I have a ub820 connected to a chunky old amp - the Denon AVC-A1SE - via analogue cables. My speakers are the reasonably big KEF THX Reference range.

I was watching my Jurassic Park UHD and found the audio less meaty than another 5.1 system I have which is newer, all HDMI, but with a cheaper amp and much smaller speakers.

As an experiment, I hooked up an optical cable from the ub820 to the AVC-A1SE and the sound was much bigger with more bass all round. For example, there‘s a moment when the raptor pokes its head under the kitchen surface and knocks over some plastic tupperware with its snout - when it quickly retracts its head there is a ’whoosh’ sound, and it always sounded ’big’ and bassy on my small system. Not so when I use the analogue cables, but through the optical it sounded great.

This baffled me because I understood that analogue gave almost HDMI levels of HD-audio, and optical was lossy and to be avoided. The optical also allows me to transform stereo into Pro-Logic and Neo, which the AVC-A1SE can’t do through its analogue inputs.

Does anyone know why I’m getting much better audio through optical than analogue?

An additional point that might be relevant - when I do a speaker channel test on the ub820, it skips the subwoofer test (when I do this on the amp, the subwoofer is present). I wonder if this is related to the weak bass I’m getting through the analogues? When I feel the subwoofer during a movie it is rumbling away, but its not nearly as active as when I go optical.

Any help would be much appreciated, thanks.
 

atmoscinema

Active Member
Yes, i've had the exact same issue on my Panasonic UB900.

I'm sure my Samsung 7500 was the same.

And two different Subwoofers.

I had to take a subwoofer out cable feed from my Yamaha E800 decoder amp into the subwoofer along with the UB900 subwoofer out cable feed too, using a phono splitter.
 
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goingoingong

Distinguished Member
I have a ub820 connected to a chunky old amp - the Denon AVC-A1SE - via analogue cables. My speakers are the reasonably big KEF THX Reference range.

I was watching my Jurassic Park UHD and found the audio less meaty than another 5.1 system I have which is newer, all HDMI, but with a cheaper amp and much smaller speakers.

As an experiment, I hooked up an optical cable from the ub820 to the AVC-A1SE and the sound was much bigger with more bass all round. For example, there‘s a moment when the raptor pokes its head under the kitchen surface and knocks over some plastic tupperware with its snout - when it quickly retracts its head there is a ’whoosh’ sound, and it always sounded ’big’ and bassy on my small system. Not so when I use the analogue cables, but through the optical it sounded great.

This baffled me because I understood that analogue gave almost HDMI levels of HD-audio, and optical was lossy and to be avoided. The optical also allows me to transform stereo into Pro-Logic and Neo, which the AVC-A1SE can’t do through its analogue inputs.

Does anyone know why I’m getting much better audio through optical than analogue?

An additional point that might be relevant - when I do a speaker channel test on the ub820, it skips the subwoofer test (when I do this on the amp, the subwoofer is present). I wonder if this is related to the weak bass I’m getting through the analogues? When I feel the subwoofer during a movie it is rumbling away, but its not nearly as active as when I go optical.

Any help would be much appreciated, thanks.
  1. Is it only bass from the subwoofer that you feel is lacking?
  2. What crossover frequency are you using?
  3. Is the subwoofer set to LFE or LFE+main?
  4. Front L/R speakers set to small or large?
  5. What happens if you turn the gain/volume up on the subwoofer?
 

Drooch

Active Member
  1. Is it only bass from the subwoofer that you feel is lacking?
  2. What crossover frequency are you using?
  3. Is the subwoofer set to LFE or LFE+main?
  4. Front L/R speakers set to small or large?
  5. What happens if you turn the gain/volume up on the subwoofer?
1. Difficult to tell but the lack of bass feels quite ‘generalised’.
2. The amp is set to ‘THX fixed’ and the sub is dialled to 90hz and the evel dial is 50%.
3. It‘s set to LFE - the only option available when your speakers are set to ‘small’.
4. Even though they’re physically big I was advised to set them to ‘small’.
5. It helps but I still don’t get that bassy ‘whoosh’ from the raptor, and when I crank it up the sub starts to ‘hum’. With optical I’m on 50%, big bass, no hum.

Thanks for your help.
 
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Graso

Novice Member
Hi did you ever sort the problem having same issues with my Pioneer AX5i bought the 820 especially for the analog outputs
 

ashenfie

Well-known Member
Don't believe everything you read. The analogue outputs are not the best unless you get something like the UB9000. A more modern AV amp with HDMI is needed to get the best out of your system.
 

Graso

Novice Member
Yes I’m sure you’re right just wondering if I’m overlooking anything obvious the 7 channels are fine it’s just the sub signal it seems the amps old but well built was considering one of the new Onkyos when available
 

Jase

Distinguished Member
Yes I’m sure you’re right just wondering if I’m overlooking anything obvious the 7 channels are fine it’s just the sub signal it seems the amps old but well built was considering one of the new Onkyos when available

If you're using the 7.1 analog outputs then you'll be restricted by whatever bass management options are available on the UB820. They look to be fairly limited going by what's in the manual.

Most AVR's don't have DSP Processing on their 7.1 External Decoder/Multichannel Inputs so all of their bass management settings are bypassed (which is why the original posters Denon A1SE was lacking bass etc).

If your AVR doesn't have DSP Processing on it's 7.1 Multichannel Inputs then you'll better off using an optical input.
 

Kapkirk

Active Member
I have similar situation to you, I can use analog but decide to use optical from the dvd to amp, the amp can handle 6.1 ch over optical and the amp does the decoding instead of the dvd player, the internal decoding in your your Denon would probably better than using analog from that dvd player in any case.
 

Graso

Novice Member
If you're using the 7.1 analog outputs then you'll be restricted by whatever bass management options are available on the UB820. They look to be fairly limited going by what's in the manual.

Most AVR's don't have DSP Processing on their 7.1 External Decoder/Multichannel Inputs so all of their bass management settings are bypassed (which is why the original posters Denon A1SE was lacking bass etc).

If your AVR doesn't have DSP Processing on it's 7.1 Multichannel Inputs then you'll better off using an optical input.
 

Graso

Novice Member
Thanks for the info I take it the optical won’t pass the newest sound formats (bearing in mind my old receiver) I’ll give it a go though.
 

Jase

Distinguished Member
Thanks for the info I take it the optical won’t pass the newest sound formats (bearing in mind my old receiver) I’ll give it a go though.

No, you'll be limited to Dolby Digital and DTS.
 

Graso

Novice Member
Do you think by passing amp and taking the bass straight to Sub could work ?I know I’d have to adjust volume on sub manually each time.
 

Jase

Distinguished Member
Do you think by passing amp and taking the bass straight to Sub could work ?I know I’d have to adjust volume on sub manually each time.
I wouldn't do that personally as you won't know the correct levels or if what you're getting is just LFE or LFE and redirected bass (depending on the UB820 settings).

I'd rather go via optical and know it's all working correctly.
 

goingoingong

Distinguished Member
Do you think by passing amp and taking the bass straight to Sub could work ?I know I’d have to adjust volume on sub manually each time.
This may be useful especially section 4.) Scotty, We Need More Bass!
How To Set up a Blu-ray Player Using Multi-Channel Analog Outputs... And Why
I'd advise you to read the entire article though.

....the subwoofer level actually needs to be boosted by about 15db in the receiver in order to get it to the "correct" output levels.

Many (if not most) receivers and preamp/processors have a special setting to boost the subwoofer for the multi-channel analog inputs. This may be called "subwoofer sensitivity" or "subwoofer level" (and it's different from the level controls for the digital inputs). Some receivers even apply this boost by default. But, other processors don't make this level adjustment so easy. If your receiver doesn't have a way for you do the required LFE boost and you think the bass sounds a little weak, you still have a couple of options.

You can simply turn up the sub
. Most powered subwoofers have a level or volume knob on the back or bottom which raises the overall output level of the subwoofer. Of course, that will give your digital sources too much bass. So, if you take this approach, you will need to recalibrate your receiver by reducing the sub output for the digital inputs. If you ran an auto-calibration routine such as Audyssey or MCACC, then you'll need to run it again with the subwoofer at its new, higher volume so that proper balance is restored to your digital sources.

The other choice is lowering the output of the non-LFE channels in the player, which has the same effect as boosting the sub. Of course, now your overall volume will end up too low and you will need to crank it up in your receiver. While this approach will get the proper bass balance, it raises the noise floor, which may not be the ideal solution


You may find a combination of the two works best for you: both turning up the sub and lowering the levels of the non LFE channels. The percentage mix though is probably something you'll have to decide for yourself. From the article you need to make a 15dB boost to the sub relative to the other channels. So, for example: a +8dB/+9dB on sub volume and -7dB/-6dB cut on the levels of other channels on the UB820.

I'd guess the main thing is not to reduce the other channels so much that you run out of amplifcation on the AVR, better to use the additional amplication on the sub and so do a more modest cut to the other channels on the player.

If going this route you'd need a dB meter for total accuracy (or a phone app) but you should be able to do it by ear which at the end of the day is telling you whether there is enough bass for your tastes.
 
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Graso

Novice Member
Thank you for your replies/guidance after much hair pulling I’ve finally sorted it!
I ended up having no bass on anything out of my AX5i tested everything by changing cables feed ect and sub was ok
Tried direct feed from sub out on 820 via analog to sub worked fine loads of bass but as mentioned could easily blow up sub I’d imagine.
Did a auto set up on amp and registered sub and set.
Still hardly any bass in the end I reset the bass setting on menu (expert I think) and it all came back bass wise and appears to be working fine on everything which I’m very pleased about I know the system is ancient but I’m fond of it!
Thank you all for advice:)
 

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