Beresford 7510 (revisited)

[Puffin]

I have recently got hold of a mint 7510 for very little money. It has not been modded (AFAIK).

I have read the mods that can be done on Stan's site and I have read all of the thread devoted to the 7510. However I cannot see what the Mod 21 Pts 1 & 2 are designed to address. I have read lots of people who said that it was an improvement, but I cannot tell in what way it was an improvement. Before I get the soldering iron out I just wondered if someone could enlighten me?

Rob.

[Labarum]

Unless you are dissatisfied with the sound I would use it as you have it.

In my judgement the effect of the mods is so subtle as to make no practical difference.

The big jump is from the 7510 to the Caiman, though I have not heard the 7520.

I have a 7510 which had Mod 21 after a few months of my ownership; and I have a Caiman.

So my advice is leave the 7510 alone and save up for a Caiman.

[Puffin]

Brian. Thanks for your reply. I think it sounds great as it is. I have a Dacmagic, and other dacs, and the Beresford is very good up against them. I get the impression from what I read on the 7520 mods thread that some modders meet themselves coming back, if you know what I mean.

[Labarum]

I get the impression from what I read on the 7520 mods thread that some modders meet themselves coming back, if you know what I mean.

I posted something to that effect recently and said I just used my Caiman as Stan sent it to me.

I was told I didn't know what I was missing!

Well, maybe, but folk do hear what they want to hear.

Perhaps the different op-amps do sound slightly different, but what counts as better?

Save your money. Flog the DacMagic and buy a Caiman.

[Puffin]

"The Spectacled Caiman is an extremely adaptable species found in virtually all lowland wetland and riverine habitats ..." (Wikipedia)

Ooeerrr?

[lovejoy]

Hi Puffin,
If you're handy with a soldering iron I'd say there are 2 BIG mods apart from Mod21 which really do make a big difference to the sound.
I changed my DAC chip to the Wolfson that the Caiman uses. That brought real improvements in terms of really tightening up the bass, sweetening the treble and improving the flow of the music. The DAC chips are pin for pin compatible, although there is a wire mod that goes with this. The details are on the Beresford website.

The other one was to bypass the op-amps and run the outputs from the DAC via 47uf/16V caps directly to the phono sockets, thus removing any sonic signature imparted by the op-amps. This one I think is a must do to get the best from the 7510 with the caveat that you have an amp which is happy working with the lower output and higher impedance of the DACs analogue output.

[StanleyB]

"The Spectacled Caiman is an extremely adaptable species found in virtually all lowland wetland and riverine habitats ..."

That's my Caiman+, which has been adapted from the Caiman and has two optical inputs. As is well known, the Caiman is extremely adaptable with a wide range of mods .

[Puffin]

Thanks Lovejoy and StanB. I wanted to make sure what the passive mod was like before I tried it. I did this to my LiTe Dac Ah and it was worthwhile.

Rob.

[Puffin]

It has occurred to me that you could cut the variable output and attach the caps there, so that you could then swap between the two.

[Puffin]

I bought some GD Discrete Op-Amps (Earth - £17 each) in order to try one of these with the B/Ford. In the 7510 the op-amp is a tiny surface mount job. Have worked with SMD a long time ago and are a real PITA!

Anyway as the GD’s need a DIL socket, it had to go. I just cut through the legs with a sharp Stanley knife. Next job was to solder on a BrownDog adaptor. The pictures make it look enormous, the footprint is about 3mm x 4mm and the pins are closer than a gnats gnat. After about an hour, got it soldered, sort of….not pretty. Put in an old op-amp and switch on. No right channel, put a bit of finger pressure on it and got R ch, but heavily distorted. Great, perhaps I should have left it alone. The pads left after removal of the original SMD component normally only give you ONE chance before they lift.


Checked all soldering for continuity, it all seemed ok, still no R channel. Problem was that the solder tip I have was way too big and was a real headache to start with. I have some other tips, two smaller ones but they would not “tin” and just gave me balls of solder.

I decide to remove the op-amp to check it is seated properly, even though I got “beeps” on all connections. I thought I would try another op-amp whilst I was at it. By now it is 9.00pm, started at 9.00am. Yes, got the R ch and the L and it sounded good.

I had to remove a 47uf cap near the phono sockets to get the soldering iron where I needed it. To fit the GD I would also have to remove the two 2200uf smoothing caps. Others have said that if you use a linear supply you don’t need them. Some have replaced them with 10uf Tanatalum, or small value Polycaps. It is also said that the diode near the PS socket is only needed in case you reverse the + & - on the input jack. It had to go as I couldn’t fit the GD with it there. I removed it and put a wire link in it’s place.


So…B/Dog in place, 47uf replaced with a Nichicon Muse, smoothing caps with 10uf tants, diode removed, GD inserted. It is now 11.00pm. Switch on…..Music, both channels! Sounds very good. Listen to a few tracks through h/phones. Go to bed.

This morning put it into main system. Initial impressions are really good. Leave to play for an hour. OMG this has got to be the best result from a tweak I have ever had. The sound is improved in EVERY way possible. The amount of low level detail is just astounding, Mids and Bass are superb, Treble really sweet. The music just flows, no one area is exaggerated over another, it is a world away from the original op-amp sound. These GD’s are I would say very analogue sounding, but not dull or woolly.

The Red caps in the pic are Black Gate 10uf used for the passive mod. I need to see what removal of the smoothing caps and diode has done to the passive mod.