Marantz cd5001 plus beresford tc7510 advice

[jflee]

Hello, I'm a newbie to dacs and, on a whim, purchased a used Beresford TC7510.

Although I am fairly happy with marantz, I thought there would be an improvement if used it with a dac. But instead find the sound less appealing, more bright and metallic sounding. I listen mostly to jazz and blues, use tube pre and power amps, and single driver speakers.

With this combination, is a degrade not surprising?

 

Thanks for any advice,

John

 

[lovejoy]

Hi John,

I've used the 7510 on the end of a number of pieces of kit ranging from cheap DVD-players, to good CD players, to computers and it's a great piece of kit, and is hugely tweakable.

 

I have experienced the same problems as you and my first question is - How are you connecting the Marantz to the 7510? When I started out, I was using an old IXOS optical cable I'd had lying around for some time and I found the sound just as you describe - metallic, harsh and thin, not in the least musically enjoyable. All this was transformed with the aid of one of Stan Beresford's own optical cables. It cost me about half the price of the IXOS but the improvement was incredible - the difference between an enjoyable and a fatiguing sound. There's also a coax digital availble.

 

If you still find things aren't what you think they should be then it could be that the transport in the Marantz isn't really allowing the 7510 to give of its best. If you have a PC/Mac with an optical output then it's really worth doing the comparison.

 

The Beresford is capable of some quite amazing sounds - as an example I took mine and my Macbook Pro to a friend's house this weekend to compare with his Naim CDS2. Now I know my 7510 has been 'breathed on' a fair bit (linear power supply, Wolfson DAC chip, op-amps bypassed with audio caps) but the whole thing still cost about 1/10th of what the Naim initially cost and the difference between the two was scarily small.

 

[jflee]

Hi Rich,

 

Thanks for the feedback - its appreciated. I'm using a toslink cable from the cdp to the dac and vanilla (but solid) analogue audio cables to a Bottlehead FPIII preamp. Although I plan to try the computer route at some point, I currently only have a weak laptop.

 

I will look at some better cabling but modifications will probably be the best route. Did you do yours? Would some basic mods be too difficult for a electronically-challenged newbie?

 

Probably wrong but I believe the marantz cd5001 is quality enough to use as a transport. If I get the dac sent out for mods, I'll ask re the cdp at the same time.

 

I have been using some supertweeters. Removing these did help with the sound; or maybe the dac is warming up a bit with some breakin (although it is a used piece). I did connect the dac/cdp to a newly acquired Melos SHA-1 preamp/headphone amp - this set-up does sounds very nice with my mid-fi cans.

 

The dac (or its power supply) is causing ground loop speaker hum - when I remove the dac the hum disappears. Have you encountered this? Any ideas on a fix for this - I think all the outlets in the vicinity of the stereo are on the same circuit so I don't think using a different outlet will take care of the hum - but I'll try this.

 

thanks muchly,

John

 

[lovejoy]

Hi John,

The ground loop hum is concerning. I've never experienced this myself and it shouldn't really happen seeing as the Beresford in stock form uses a switch mode power supply. It would be worth dropping an E-mail to Stan Beresford. He's always incredibly helpful and if anyone has an answer it will be him.

 

If you're not handy with a soldering iron then I'd recommend against trying to perform any mods yourself. Some of the jobs are quite fiddly and I've almost ruined my own DAC a couple of times trying various things.

 

I'm not sure about the quality of the cd5001 as a transport. All of the CD players at that level I've ever played with the digital output from I would rate "competent", but generally outclassed by even the lowest specced PC with a digital output.

 

There are a handful of tweaks you can perform on the cd5001 to improve it considerably. A quick Google has turned up a few pages of info over on diyaudio, but again these jobs are best left to people who know their way around a circuit board.

 

Rich

 

[jflee]

Hi Rich, thanks for the info and help.

I'll do some more cable re-organization before contacting Stan Beresford, but its nice to know he's approachable.

 

I think I need more practice with the iron before doing any dac mods and also need to get a much smaller iron tip - the soldering connections points look very tiny.

 

Interesting - so a basic cd-dvd tray/transport is generally better than

the transport in a mid-hi standalone cdplayer? Then, when looking for a computer system, a super quiet model is one to keep in mind - then it can also be used as the cd-player and housed with the in the main living area.

 

Rich, regarding modding the tc7510, which change do you think would

make the biggest improvement?

 

thanks,

John

 

 

[lovejoy]

Hi John,

To my ears, the biggest difference came from getting rid of the standard wall-wart power supply and replacing it with a linear 12V supply. I guess this is the easiest mod to perform as it doesn't involve taking the lid off the DAC. I use a "TeddyReg" connected to a transformer outputting 18V. The TeddyReg then supplies the DAC with nice clean 12V.

http://www.teddypardo.com/

A further improvement to this can be had by removing the reservoir capacitor inside the case, but only if you're not likely to go back to the switch mode supply.

 

The second biggest improvement came from swapping out the PCM1716 DAC chip for a Wolfson8716. They are pin for pin compatible and apart from soldering an SMD chip (which is not for the fainthearted) there are only a couple of wire mods to perform.

 

The third big change then comes from bypassing the op-amps in the output stage and having nothing but DC blocking caps between the DAC chip's output and the phono sockets. I think this one is more system dependent though. You could alternatively swap the op-amps for higher quality components. There is a company called Tirna Electronics that will perform this upgrade for you, amongst others.

 

[rooob]

Cut your loses, don't mess around with the Beresford sell it and get something a bit better.

Something like this

http://cgi.ebay.co.uk/Valab-TDA1543-NOS-USB-Re-Clock-DAC-Independent-Power_W0QQitemZ270524904234QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3efc8a732a

The 7510 has been totally overhyped by some esp in the UK, it is a budget product with a budget sound, something like the product I have linked or its cheaper brother that comes without the external power supply should suit your musical tastes.

http://cgi.ebay.co.uk/Valab-NOS-USB-Re-Clock-DAC-Low-Jitter-Dual-1ppm-TCXO_W0QQitemZ290391486905QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item439cae71b9#ht_5957wt_941

 

[jflee]

Thanks for the suggestions, I always keep an eye for product - and my wife's ready to take me out behind the shed...

 

I'll stick with the beresford for a bit - and maybe try to learn something about using the computer as a good source. and Rich, I'll try updating the power supply, but with something around here - Toronto - there's a couple of audio parts vendors nearby that I'll inquire with.

 

thanks again,

John