AV9 & P7 with Rothwell Attenuators.....Anyone tried it?

texasboy

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Hi all,

Has anyone tried the above?

Attenuators

Keep hearing good things about them.

My system is as follows

Sonos ZP80 feeding FLAC files into a MF KW DAC
AV9
P7 with 4 channels biamped on Spendor S9e
with a Audyssey MultEQ between the AV9 & P7

I obviously would need to buy 7 of them (centre and rears as well) and EQ everything again I guess?

I suppose with the relatively low cost I could try them and sell them on eBay if they don't offer any improvement.

Anyone tried??

Thanks :)
 
I don't know anything about theses attenuators, but I am very interested, like you, to see if someone has ever use them and the impact they have. My wife will also be happy!
 
£39 for a pair of resistors that probably cost 2p each is daylight robbery. If you really want to do this, go to your local branch of Maplin, buy two resistors of the relevant size, a couple of phono plugs and some phono line sockets. Total cost will be about a fiver...

Or just build them into your existing phono cables - desolder the wire from the centre pin at one end, solder resistor into the gap. Total cost for 7 channels will be 14p plus the solder.
 
"Although potentiometers work reasonably well over most of their operating range, they are notoriously problematic at extreme settings. The most obvious problem is channel imbalance - one channel will fade out (or fade in) quicker than the other, causing the stereo image to shift to one side - but on a more subtle level, the music may sound veiled and indistinct with the volume control turned down to the point where it is nearly off."

Since Arcam products use precision electronic volume controls rather than potentiometers, this argument is invalid.
 
Go to page 18 of your Arcam AV9 manual and you will see that you have the option to set the input sensitivity of any analogue input to either 1 2 4 or 8 volts. If your MF dac is outputing more than 8V rms then you have a problem that might be fixed by these attenuators.

I seriously doubt that that is the case and would suggest you don't waste your money as has been previously stated.

Ask yourself this... At what point on the dB scale is the volume too loud? If you are looking at 30 - 40 db then you need to increase the input ref.. If it's 70 -80 db then you system's doing just fine.. If you can't get it loud enough then attenuator aren't going to do you any good at all and you need to buy a bigger amp..

You have a fantastic DAC but you are driving it from such a poor source... My advice would be to buy an MF A1008 CD if you really want to hear the music as it should be, or any player with a Philips Pro 2 drive.

You might also want to consider a bigger amp....
 
You have a fantastic DAC but you are driving it from such a poor source... My advice would be to buy an MF A1008 CD if you really want to hear the music as it should be, or any player with a Philips Pro 2 drive.

Do you have any evidence at all to support your claim that a Sonos ZonePlayer is a "poor" digital source? I'm using one into my AVR350, and I can detect no difference at all between it and the same CD played back on my DV137. Even if one accepts that jitter makes a big different to sound quality, do you have any evidence to suggest that jitter is higher from a Sonos than from a CD player? Because there is no other reason why there would be a difference. Lossless files from a media streamer feed exactly the same bits into the DAC as the original CD does.
 
I compared the Sonos ZP80/KW DAC against numerous different CD players/transports and differences were not apparent to my ears until I got close to the 3k mark.

This I could not justify, that money went on buying my ex-demo Audyssey for £1,000 and having a nice holiday.

I've also got a DV139 which is connected to the AV9 for DVD and also the KW DAC for the odd time I want to listen to CD - I cannot tell the difference between this and the Sonos. I have 230GB of music all FLAC on a NAS drive, like I said above until I got up to 3k on a dedicated transport differences were few and far between, the convenience of the Sonos swung it as much as anything.

I'm more than happy with the sound I have I was just intrigued as to what the Rothwell things would do and whether they'd be worth a punt. I'll buy some more BD movies instead.

FWIW, the best upgrade I have ever, ever made (by like a million miles) was the Audyssey, stunning, both for music and movies.
 
I auditioned the Sonos ZP80 about a year ago, it was hooked via digital to a Denon AVC A11 and B&W 805S. I took along my CD36 and hooked it up via the analogue outputs and ran them side by side. I didn't try the digital connection from my CD36 because I don't use it that way at home. The shop claimed to have demo music ripped apple lossless so it was as good as could have been expected. Re the Sonos, I thought the image was narrow and it sounded flat, compared to the CD36 which had a much wider sound field and sounded more lively. The test didn't last more than 15 mins. I wasn't impressed.

I was still determined to find out more about music streamers so a month later I got a good deal on a Transporter.. Humm.. same as the Sonos.. Not up to the same wide sound field as the CD36.. perhaps a bit better than the Sonos but it wasn't the same music in the same system so perhaps not a fair comparison... I sold the Transporter after 6 weeks.

Going back to 'attenuators'. Their claims about improving signal to noise are somewhat disturbing. If you put an attenuator in the line you are introducing noise. It's a resistor that naturally generates thermal noise, no matter how much they might claim it's low noise, metal film etc. Also, you are reducing the signal at the input to the amplifier which in turn means it's closer to the noise in the amplifier input stage. Because you then have to turn up the gain of the amplifier to reclaim the attenuated signalyou are also amplifiying the noise from your input stage and the noise from the attenuator.

Try setting your ref voltage to 4 or 8V and see what that does. Each step is like putting a 6dB attenuator at the input.. and it's free :thumbsup:
 
I auditioned the Sonos ZP80 about a year ago, it was hooked via digital to a Denon AVC A11 and B&W 805S. I took along my CD36 and hooked it up via the analogue outputs and ran them side by side. I didn't try the digital connection from my CD36 because I don't use it that way at home. The shop claimed to have demo music ripped apple lossless so it was as good as could have been expected. Re the Sonos, I thought the image was narrow and it sounded flat, compared to the CD36 which had a much wider sound field and sounded more lively. The test didn't last more than 15 mins. I wasn't impressed.

But that wasn't a fair test - in the main, all you were doing was comparing the DAC in the Denon to the DAC and analogue output stages in your CD36. This introduces enough variation that you can't claim to have compared the quality of the Sonos as a digital source to any other digital source. For all you know, what you didn't like was the sound of the Denon's DAC, or you just preferred the tonal character of the CD36's analogue output stage. Unless you have actually compared the digital outputs of the two products, any judgement as to whether or not the Sonos is a poor source is meaningless.
 
Hi,

Cjohson6, just a quick post to tell that, if you have not been impressed by the Sonos under the circumstances you described, my suggestion is to try to arrange anew demo but in a shop that knows what it's talking about.
For some reason that I can't explain technically, the so called "ALAC" format (Apple Lossles Audio Codec) delivers really weird results.
You should try the same with .wav or .aiff files or, provided they have some files o that kind, ones that are compressed into FLAC.
And the "ripping" of the CD should not be made with iTunes, or if it is, the "CD error correction" option should at least be activated. But there are other programs that re-red the CD when the detect an error correction from the drive.
the difference between files correctly ripped and not correctly ripped is simply stunning !

Regards.

Gallows Pole
 
whats the advantage of a Sonos vs say an ION based micro PC ?
 
For some reason that I can't explain technically, the so called "ALAC" format (Apple Lossles Audio Codec) delivers really weird results.
You should try the same with .wav or .aiff files or, provided they have some files o that kind, ones that are compressed into FLAC.

Do you have any more information on this? I find it very difficult to believe that there are any such problems with the ALAC codec.

If you rip a CD with HDCD encoding and compress it using ALAC, the bitstream from a ZP80 is detected as HDCD-encoded when the file is played back through an HDCD-compatible DAC. (I know this for a fact, as I've tested it myself.) HDCD is an encoding stored as specific patterns in the least-significant bits of the PCM audio data - if HDCD flags are still being detected, it proves that you are getting exactly the same bitstream after lossless compression that you had from the original CD.

I agree that iTunes is not a good ripper, and that may lead to problems with scratched or poorly-mastered discs, but if there was a problem with the Apple Lossless codec, someone would have noticed by now! (Testing a lossless codec is easy and completely non-subjective - did I get the same bits out as I put in? If so, it works; if not, it's broken.)
 
Hi SPL23,

No more information than my own experience... that has afterwards been confirmed in 2 different high-end magazines here in France.
When I got my AppleTV, I ripped some CD's i knew really well using iTunes and the Apple Lossless format. Then I listened to the tunes and thought : "OMG, is this the "digital wonder" everyone's speaking of ?" There was no dynamic, the frequency ranges seemed to be shortened, the music was not accurate... It wasn't "bad" for a 300£ device, but definitely not what I was expecting.
Then I tried to ripp to .AIFF or to .wav (the latter isn't convenient as it won't store CD covers...) and even to FLAC (had to tweak my iTunes AND my AppleTV to read the .flac files). All the sudden, the music was almost on par with my Arcam CD23T CD player. All it lacked was a deeper soundstage and a little more of the "vivid sound" from the CD23T.
Why this did happen ? Please, don ot ask... I don not know. But this is what I experienced. I will of course say that, in between the 2 testing sessions, nothing has been changed to my system :)

Regards.

PenguinHiFi
 
No more information than my own experience... that has afterwards been confirmed in 2 different high-end magazines here in France.
When I got my AppleTV, I ripped some CD's i knew really well using iTunes and the Apple Lossless format. Then I listened to the tunes and thought : "OMG, is this the "digital wonder" everyone's speaking of ?" There was no dynamic, the frequency ranges seemed to be shortened, the music was not accurate... It wasn't "bad" for a 300£ device, but definitely not what I was expecting.
Then I tried to ripp to .AIFF or to .wav (the latter isn't convenient as it won't store CD covers...) and even to FLAC (had to tweak my iTunes AND my AppleTV to read the .flac files). All the sudden, the music was almost on par with my Arcam CD23T CD player. All it lacked was a deeper soundstage and a little more of the "vivid sound" from the CD23T.
Why this did happen ? Please, don ot ask... I don not know. But this is what I experienced. I will of course say that, in between the 2 testing sessions, nothing has been changed to my system :)

So you didn't actually back-to-back test them - there was some period of time between you listening to the ALACs and you listening to the AIFFs? It would be interesting if you tried it again - store the same track in both ALAC and AIFF/WAV on your AppleTV, play it back and see if you can tell them apart. To eliminate the possibility of iTunes having done the rip badly (which is entirely possible, but is nothing to do with the ALAC codec itself), use iTunes just to convert your AIFF/WAV (which you know sound good) directly to ALAC.

There is no difference at all in the output bitstream between ALAC and AIFF/WAV - that's a fact, and can easily be proved. You are also less likely to get corruption in the ALAC file than in AIFF or WAV, as it uses half the bandwidth in transmission, and is sanity-checked when it is unpacked. It can't be that Sonos have made a mess of their ALAC decoder implementation, as otherwise my tests with HDCD streams would have shown problems. (Although if you are using an AppleTV rather than a Sonos, I suppose it is possible that there is a problem in the ALAC decoder in the ATV. Seems very unlikely though - as Apple designed the format, they ought to be able to implement it!)

As your listening to ALAC and AIFF/WAV was not in the same session, I can only conclude that *something* else had changed between the two listening sessions, as there is no technical reason for a difference between ALAC and AIFF/WAV. It wasn't that you used the digital output of the ATV for one session and the analogue outputs for the other, was it? I can well believe that the DAC and analogue output stages in the ATV aren't great, and that might account for a difference.

I'd be interested to see what the French magazines said - do either of them have the articles about their testing online anywhere?

Edit - actually, on browsing threads on this topic elsewhere, it does seem possible that some playback devices may have problems with properly reconstructing the original WAV from the Apple Lossless file, and I guess it is possible that the comparatively puny processor in the Apple TV may fall into this category. I'd be interested to see if HDCD data gets out of an ATV correctly from an ALAC file.
 
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Hi Penguin, I gave up on music streamers and now just use my Electrocompaniet EMC-1UP. I don't even like the streamer in the Denon AVC-A1HD much.. In many ways it's like the Transporter I used to have.. quirky...

The Electrocompaniet has such a smooth and relaxing sound, and I still like the idea of handling the disk and reading the cover notes ( all adds the to listening experiance ). :)

Understand this has nothing whatsoever to do with attenuators.. Sorry Mods..
 
Hi SPL23,

Just read your post.
I'll try to do what you're asking and will transfer the files in both formats.
I'll even do more :
- I'll try both formats to be read into the standard "iTunes" implemented into the AppleTV ;
- I'll then try the same files but read with another application that I have added to my "tweaked" Apple TV ;

So far, what I have to tell is that music downloaded from "Linn Records" in .flac and played on the AppleTV (using ATVFlash to make the AppleTV accept .flac files) are without any doubt highly superior to the ALAC files read by the original app.

I'll post the results as soon as I can.

Regards.

Gallows Pole

P.S. : I'll do this with a friend of mine to be sure I'm not fooled ;-)
 
So far, what I have to tell is that music downloaded from "Linn Records" in .flac and played on the AppleTV (using ATVFlash to make the AppleTV accept .flac files) are without any doubt highly superior to the ALAC files read by the original app.

Now that's very interesting. FLAC and ALAC are actually quite similar codecs, and they are certainly similar in terms of processing power required to unpack to uncompressed audio. If it is indeed true that ALAC sounds worse than FLAC on the ATV, it can't be a simple processing power issue - it must be a problem with the implementation of the ALAC codec.

One thought - are the Linn FLAC files standard 16-bit 44.1kHz? I had an idea that Linn were selling higher-res files - 24-bit 96kHz? That would explain a difference - plus anything Linn are selling is likely to have had a lot of care taken in the recording. Although a higher-res file is going to need more processing power to decode than a standard ALAC anyway - very odd.

It might be interesting to convert one of the Linn FLACs to a 16-bit 48kHz WAV, and encode that WAV as ALAC, and then compare the three files?
 
I have the ATV going into the avp into the p7 and outputting to my kef xq40s

There is no difference between ALAC and WAV file output and actually CD output from my ARcam DV137. So, I think something must be faulty with either the ripping or the setup on your itunes.

I would check the settings on itunes again
 

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