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Labarum
2008-11-01, 05:25
Just installed SB3. Twas easy and quick. I had Squeezecentre installed on the study PC already, and had been reviewing the product using Softsqueeze on an old Shuttle PC behind the TV in the lounge.

Of course SB3 is clearer and cleaner - and silent!

I do notice a very big difference in volume between streamed radio and the FLAC files on my hard dive.

I run SB3 at or close to max volume - its nice to have a remote volume to hush the adverts and other speech. For Radio the Beresford variable output potentiometer needs to be at about 9 o'clock, but when streaming FLAC it needs 12 o'clock.

Is this to be expected, or am I missing some buttons somewhere?

jeffmeh
2008-11-01, 06:32
This is common, in my experience. I use replaygain through SC, and I find most SN streams to be louder.

Labarum
2008-11-01, 06:43
This is common, in my experience. I use replaygain through SC, and I find most SN streams to be louder.


Thanks. And is there a quality issue using replaygain?


(Just a few minutes ago I tried the analogue out from the Squeezebox - ouch - is that rough compared even to my Beresford DAC?

I look at the price of the Transporter and baulk - a 24/96 "Receiver-Audiophile" is all I need - just the streaming hardware with a good digital output.

The research and development work has bee done - what do you think the chances are?)

Phil Leigh
2008-11-02, 00:25
Brian - I've been following this thread with a view to hopefully offering some helpful opinion, so here goes:

1) the SB3 is 24-bit internally. It's volume control works as well as any other 24-bit implementation I'm familiar with - ie very well indeed. You have to get the volume down below -20 or so(which in hearing terms is quite a lot) before there is any possibility of audible impacts to the quality.

2) You mention squeezenetwork which serves low-medium quality compressed formats. I'm not 100% sure about this but it is possible that in addition to the lossy compression, the files may be normalised/compressed/limited in an attempt to make them seem louder - just like the commercial FM stations used to do... if so this is really bad and would explain why SN is louder than your flacs.

3) I use replaygain extensively and have never heard any deleterious impact. Bear in mind that even a very compressed/clipped "loudness wars" CD will probably only take -10 dB of RG so quality should not be impaired.

4) the 405 amp has a sensitivity of 500mV for full output. Unless you have had this modded, this is too sensitive for the output of a (non-Quad) Pre-amp, CD or DAC which can easily put out 1-2 volts!. IF the volume control on your dac is basically a passive pot right at the output, I'd want to keep it at no more than 50% (unless your 405 sensitivity has been modified).


5) Why do you need 24/96? - do you have any flacs in that format? Your SB can do 24/44.1 and 24/48 which is more than adequate for normal CD's... are you looking to get hi-res downloads (eg Naim, Linn etc)?

In summary, I think you should:

1) realise that squeezenetwork is a quality-compromised that doesn't really compare with the FLAC world - but then it's not supposed to.

2) use replaygain and the SB volume control (digital level adjust) for adjusting general listening level and making those SN stations quieter

3) set the vol on your DAC to max 50% or...

4) think about adding inline attenuators between dac and amp which will expand the useful operating range of the dac vol control and protect the amp from being overloaded - unless the amp has been modded already to reduce its sensitivity to 2V.


Best regards
Phil

Labarum
2008-11-02, 01:13
1) realise that squeezenetwork is a quality-compromised that doesn't really compare with the FLAC world - but then it's not supposed to.

This I do realise, but I am surprised how good the Squeezenetwork, internet radio and Virgin Media cable Box outputs are at 128Kb/s - as I said as good as my Quad FM tuner; though I will admit I was not in a position to make a fair comparison because in my present house I can get no Band II reception and had to pull the FM signal of the cable - even that has now been turned off.



2) use replaygain and the SB volume control (digital level adjust) for adjusting general listening level and making those SN stations quieter

That I will try, although it is not too difficult to use the analogue volume control, which is, in the Beresford, a pot near the end of the electronics. It is nice to know that I can go down to 20% on the digital volume.



3) set the vol on your DAC to max 50% or...

4) think about adding inline attenuators between dac and amp which will expand the useful operating range of the dac vol control and protect the amp from being overloaded - unless the amp has been modded already to reduce its sensitivity to 2V.


The 405 was modified to decrease it's input sensitivity as I knew this was an issue when I sent it off.

Thank you for your interest. I am not "busting a gut" to go 24/96 because, as you say, there is not much out there yet and I have an extensive collection at 16/44.1. I do not mind spending 120 on a box that limits me to CD quality, but at this stage in the game I would not spend much more, especially since SB3 seems to be doing the biz.

Phil Leigh
2008-11-02, 04:15
Brian - just to clarify the SB volume/quality issue, what I meant was you can safely go down to -20dB (of attenuation) - as shown on the SB3 volume display. Actually if you try it in all probability you will find that you can go down more than that without noticing any difference. However, as you do this, bear in mind that any noise from the output stage of your DAC is not being reduced, so your signal to noise ratio is worsening...
regards
Phil

Labarum
2008-11-02, 04:31
Brian - just to clarify the SB volume/quality issue, what I meant was you can safely go down to -20dB (of attenuation)

Thanks. Still early days for me.

I will use the digital volume control sparingly - it really comes into its own for winding down adverts and even commentary. The balance between speech and music is usually set to suit a portable radio and not a competent HiFi, although I do miss the Quad 77 remote with its old fashion rotary control. I have heard it said that, in a good system, a volume control is really a "Focus control" - I think I agree. I could put the Quad 77 amp back in circuit and use it as an analogue pre-amp, but that's an extra stage of analogue degradation.

Interestingly, the modded 405-2 is slightly better than the Quad 77 Integrated Amp. I bought the 405 on eBay for 135 and the upgrade cost 80 - all new capacitors (signal and power), new central op-amp and various other mods to bring it closer to the latest 909. Nominally 100w instead of 80, but gives much firmer bass, more clarity in the mid-range and more top-tingle but without any roughness.

Next job is to try the Beresford with Mod 21 which is supposed to be a big improvement. Members on other forums tell me that.

And for all of this I ain't spending a fortune.