Mod your Beresford TC-7510

[leo]

Op-amp rolling is obviously the easy stuff to try, should also bring noticeable differences to the sound.

LM4562 are very good but need care to get the best out of them, their also not much good at driving capacitive loads

Did you ever try the NE5532 instead of the JRC4558 Stan? I know the 5532 is frowned upon by a lot of people and classed as old tat but they are actually capable of decent results

Of course they don't have the speed,bandwidth, ultra low noise as some of the newer types but they are cheap, DC offset can be higher but used on a single rail with DC blocking caps it shouldn't be a problem

For the more expensive so called Audiophile grade theres AD8620, AD8065, LM4562, OPA2132,OPA2134
All of those should work on a single rail, theres lots more that could be tried too

[Stratmangler]

Starting with the simple upgrades that do not require opening the DAC:


One of the first things people ask me is what they can do to upgrade the power supply. The one I ship with the TC-7510 is a regulated version that works on anything between 90V to 260V. However, a regulated linear power supply of at least 300mA and not more than 15V off load gives better bass handling ability and a fuller sound.
The Maplin unit at POWER SUPPLY
is also a good upgrade, and frequently mentioned. It is also on offer right now.

I've been using one of the Maplin PSU units for the last year, and it is a very good, inexpensive upgrade.

Would a stiff linear PSU be an improvement over the Maplin unit ?

Thanks for the Mod 21 pdf Stan.

Chris

[NRG]

I've been running a 12v ALW on the Beresford DAC for a while and IMO it's made a huge difference to the sound, I bypassed the in-line diode as well. I also replaced the o/p 'lytics with some 100uF BlackGates and junked the bypass ceramics and replaced them with MKS Wima. The input 'lytic to the opamp I replaced with some Nichion Fine Gold caps and I've also replaced the 4558 with an OPA2134. They are little blighters to desolder but I managed it without destroying the PCB tracks.

Not sure if the opamp is an 'improvement' but it does sound different, much more like my Naim CD player which may not be all that surprising as it also used the OPA2134...there are better opamps available but I like the 'tone'.

I've also implemented part of Stan's MOD21 by bypassing R11/R14.

I next want to bypass the 10v reg feeding the opamp and take the ALW 12v straight into it. I also think there may be a benefit by adding a second ALW regulator to feed the critical DAC circuit...

[Ali Tait]

Well I've done part of the mod21 in that I've replaced the caps with Black Gates (Only 20 or so quid from Hificollective) and making solder bridges across the resistors.Has made a big improvement.I also have some opamps to change but haven't got round to doing them yet.I'm still using the stock wall wart so I'll have to get one of the Maplin ones.I'm a bit loath to do much more coz the new ones coming out soon! Look forward to reports on how much of an improvement it is on the current one.

[leo]

Are the ALW's stable driving those big caps on the 7510's DC input Neal?

Good idea supplying the dac and op-amp with better regs, just a shame the ALW's are so big

[StanleyB]

Op-amp rolling is obviously the easy stuff to try, should also bring noticeable differences to the sound.

LM4562 are very good but need care to get the best out of them, their also not much good at driving capacitive loads

Did you ever try the NE5532 instead of the JRC4558 Stan? I know the 5532 is frowned upon by a lot of people and classed as old tat but they are actually capable of decent results

Of course they don't have the speed,bandwidth, ultra low noise as some of the newer types but they are cheap, DC offset can be higher but used on a single rail with DC blocking caps it shouldn't be a problem

For the more expensive so called Audiophile grade theres AD8620, AD8065, LM4562, OPA2132,OPA2134
All of those should work on a single rail, theres lots more that could be tried too

I am using the 5532 in the 7510+. I got little time for people who work out the theory but don't try out a component in the circuit it is intended for. Decades of fault finding and circuit modification has taught me a lot about when to abandon theory and use one's ears instead. A bumble bee can't fly after all according to the theory.

The LM4562 is being used by quite a few people in their modification of the TC-7510. I also know of one guy who uses a double OPA627 on a Brown Dog adapter.

The PCM1716 can also be replaced by the WM8716, but there are two extra track mods that are required in order to get it to work properly. The WM8716 hasn't got the analogue filter built in like the PCM1716.

[StanleyB]

Would a stiff linear PSU be an improvement over the Maplin unit ?

Linear sounds better, and battery sounds best. I used to ship them with a linear PSU, before switching to a switched mode PSU. But I still use the linear PSU on mine.

[StanleyB]

The input 'lytic to the opamp I replaced with some Nichion Fine Gold caps and I've also replaced the 4558 with an OPA2134. They are little blighters to desolder but I managed it without destroying the PCB tracks.

I shall now teach you guys the best way to desolder a suface mount IC.
1. Get a Stanley knife with an absolute spanking new blade.
2. Press down gentle on each IC leg of the IC with the sharp tip of the blade till the blade has cut through the leg. It is important that you press down on the leg! Don't try it any other way.
3. Once you have cut out all the legs, whip the IC out.
4. Use a soldering iron with a flat end on the tip.
5. Rest the tip on each of the cut out leg that is still soldered to the PCB for about 2 to 3 seconds.
6. Now move the solder tip in the direction of where the IC body used to be. This will dislodge the soldered leg. Because there is no soldered component in the area where you just swiped the iron tip towards, the leg will not stick to any adjacent part.
7. If you lift the tip up now, in most cases the leg will still be stuck to the iron and you can then clean it off on a wet sponge.
8. The area from which you just removed the IC should now be cleaned with something like meths or so. Then you can just put the new IC in the same space.
9. Press down on each leg with the flat end of the solder iron tip for about 3 seconds. When you lift the soldering iron tip up the IC leg should now be soldered onto the PCB as if by magic.

Notice that at no time did I mention to use solder to solder anything. All donations are most welcome.

[Covenant]

I take it Stan that all these mods are totally eclipsed by the 7510+?

[StanleyB]

The 7510+ is not a replacement, but an addition in my line up. Not everyone wants USB or the addition of a more expensive headphone amp section, or wants to do opamp rolling for that matter. And fewer still are using their DAC as a digital preamp. So I don't expect it to be selling just as well as the TC-7510.
I see the 7510+ as a specialized product that would be more of interest to people who want something close to Chord64 like performance at less than £200. The TC-7510 is more aimed at the high-end CDP substitution market, as many a Naim, Linn, and Wadia CDP owner who got a TC-7510 can testify to.