View Full Version : modded 7510 vs 7520

09-03-2009, 11:57
I know there is a plethora of topics already but I couldn't decide which one to put this in. So I've started another one.

I had the 7510 with a Mod21 for 5 or 6 months before getting the 7520. The 7520 certainly was an improvement over the 7510. As the 7510 was now "redundant" I decided to experiment with some of the further mods mentioned on here. The ones I went for consisted of the 4 x 47uF 16V Black Gates, an LM4562MA Op-Amp and a Wolfson WM8716 DAC chip.

After getting the modded 7510 back and burnt in for a few days I'll try to give a summary of what I have heard so far.

Firstly, the Wolfson DAC isn't exactly a drop in replacement for the original. It needs some extra analogue filtering. This means that when the DAC isn't being fed a signal you get some extra noise which is heard as hiss. When the input becomes live however the hiss disappears. A bit annoying at high volumes but no excessively so during normal listening volumes.

This is the set up I have been using:

Streamed Apple Lossless files from iTunes via an AppleTV: Chord Optichord: 7510/7520 (Maplin PSU at 12v): Chord Cobra 3 Phono to DIN: NAC 202 (HiCap & NAPSC): NAP250.2 : NACA5 : B&W 804s

I played a few different tracks (Kate Bush : The Architects Dream off Aerial, Kraftwerk : Radio Activity off The Mix and Porcupine Tree : Even Less off Stupid Dream) this morning switching four or five times between the two DAC's.

Here's a quick summary of some notes I wrote:

7520: Airy presentation, good detail but not as big a soundstage.

7510: Fuller & bigger soundstage. Smoother sound although occasionally more slight sibilance on some vocals. Definitely more bass presence but a less pronounced mid range. Less "digital". For instance, the initial drum build up on the Kate Bush track is more realistic to my ears with the 7510 and her voice seems fuller. I found myself tapping my foot along more with the 7510.

Now I prefer a more bass driven sound whereas others may not so I'm speaking out of a personal preference plus the mods to the 7510 have now brought it to a higher cost than a standard 7520. The mods have certainly changed the character of the 7510 and I guess I am just getting used to this too although I can say I preferred the 7520 over the 7510 with the Mod21 I am leaving the 7520 plugged in for now! I'll go back in a few days time to re-assess.

Roll on the mods for the 7520!

09-03-2009, 22:02
Both DACs are miles ahead of the CD5x I must add.

09-03-2009, 22:19
Both DACs are miles ahead of the CD5x I must add.

Thats not a hard task:lol: (just pulling your leg)

I've seen a pic of inside the 7520, well at least the op-amps will be easier to do a spot of rolling

A few other bits and pieces worth playing with too:eyebrows:

Poor old Stan, its not been out two minutes and already folks are wanting to mod it