Mod your Beresford 7520

[Shanedudddy2]

Thanks, finding the resistor value would be great
Sound quality is most important ^_^, im suprised that u hadnt tried 4562 however

[lemon]

...
Due, to lower Vrms output...1Vrms, you need to give more power to have the same level of sound...

Forgive me the ≈1Vrms output is for Wolfson 8716 DAC not for 1716DAC.

Some technical about outputs for yours info (note= the DAC has changed with Wolfson 8716).

Direct Output L = VACrms 1.11 (1KHz sinus, 0 Dbfs)
Direct Output R = VACrms 1.11 (1KHz sinus, 0 Dbfs)
Fixed Output L = VACrms 2.32 (1KHz sinus, 0 Dbfs)
Fixed Output R = VACrms 2.34 (1KHz sinus, 0 Dbfs)
Variable Output (max) L = VACrms 2.32 (1KHz sinus, 0 Dbfs)
Variable Output (max) R = VACrms 2.33 (1KHz sinus, 0 Dbfs)
(measure has done with Fluke 45)

1 KHz sinus (the two signal has adapted (Volts), for comparison reasons)


20 KHz sinus (the two signal has adapted (Volts), for comparison reasons)


From ≥5KHz the two signals begin and different stages. The signal of direct output precedence over the label fixed (I do not know if I wrote correctly).

Can someone explain to us, for what reason happening?

[Cubeman]

Sweet Mary, nobody told me op-amps and the Wolfson chip where so small
Just received a bunch of op-amps like the Tirna "modified" THS4032CD, one LME49720HA and two LM4562NA's along with an Wolfson WM8716 DAC chip.
But to small for my fat fingers I have to admit, at least the DAC chip is

And thinking I thought about doing the Wolfson DAC chip myself, no way in the next 2000 years
Better just send my 7520 to Tirna to get this done...

Martijn

[Covenant]

Sweet Mary, nobody told me op-amps and the Wolfson chip where so small
Just received a bunch of op-amps like the Tirna "modified" THS4032CD, one LME49720HA and two LM4562NA's along with an Wolfson WM8716 DAC chip.
But to small for my fat fingers I have to admit, at least the DAC chip is

And thinking A thought about doing the Wolfson DAC chip myself, no way in the next 2000 years
Better just send my 7520 to Tirna to get this done...

Martijn

You wont be sorry-they know what they are doing.

[Puffin]

Covenant. You have PM.

[Cubeman]

You wont be sorry-they know what they are doing.

Sweet! Today I changed my fixed/variable op-amp with Tirna supplied THS4032CD model.
Man, what a difference! I could never have expected it to be so obvious
Deeper and more controlled bass, overall crisper sound, various instruments can now be distinguished from one anther and everything sounds more controlled.
Better sound stage, blablabla

Fed my 7520 with some 24-bits 96KHz Vinyl Flac tune from my Macbook straight through optical from the output.
Put on some tunes from Tool, albums Undertow and Saliva.
Man what a sound, my system never sounded so good.
The music of both albums is filled with roaring bass, tiny little details, hauling guitars and at time sensitive and fragile vocals.
I really believe I now hear more of the details in the music, nice one!
The monster came allive today

Wonder what a Wolfson DAC upgrade would do

Martijn

[ZebuTheOxen]

Very nice Cubeman!

Today I popped down to Maplin and picked up some replacement capacitors (note: Do not use Tantalum caps for MCL 5 / 6, they sound awful) and picked up a 6-pin DIL socket.

6-pin DIL? Ohhhhh yes!
I chopped it in half with some wire cutter pliers, popped out the middle pin on both halves, trimmed the nasty bits, shortened the legs a tiny bit and soldered the remaining two legs into the MCL 5 + 6 positions.
I can now swap caps / resistors in these positions much more easily

Sound is unaffected, and significantly improved having swapped out the Tantalum caps.

I got the suggestion for the socket from another thread, thanks to whoever mentioned it - great idea!

I've got a bottle of Glenfiddich 18 y/o and my CD collection, a good kind of saturday night

[Cubeman]

Very nice Cubeman!

Today I popped down to Maplin and picked up some replacement capacitors (note: Do not use Tantalum caps for MCL 5 / 6, they sound awful) and picked up a 6-pin DIL socket.

6-pin DIL? Ohhhhh yes!
I chopped it in half with some wire cutter pliers, popped out the middle pin on both halves, trimmed the nasty bits, shortened the legs a tiny bit and soldered the remaining two legs into the MCL 5 + 6 positions.
I can now swap caps / resistors in these positions much more easily

Sound is unaffected, and significantly improved having swapped out the Tantalum caps.

I got the suggestion for the socket from another thread, thanks to whoever mentioned it - great idea!

I've got a bottle of Glenfiddich 18 y/o and my CD collection, a good kind of saturday night

Nice one ZebuTheOxen!

Been enjoying myself last saturday night with some great music, some Endradour 10y/o and Laphroaig Quarter Cask

Martijn

[jcgrant]

hi first post here

just purchased a beresford 7520 of ebay a few weeks ago . What a bit of kit!!!

it came with an uprated op amp which had never been installed . First impressions 'out of the box ' was good, it brigthened up my old marantnz cd52 mkii .

Being a bit of a tinkerer the lid was quickly removed and the new op amp installed (its the one with cap connected between pins 4-8) . To be fair this did take a bit to burn in but over all i think the bass and depth of the music has increased a good deal.

Today I changed alll the 100uF caps with better ones (nichon audio spec i think low esr etc.)and there has been a noticable difference straight away . All other caps will eventually be changed, even the 10000uf power cap , when time/funds/delivery permits.

next on the agenda will be installation of the wolfson dac chip, I ve got one on the way but with the xmas post crisis that could be a week or too!

eventually i hope to change the voltage regulators with some quieter versions, and either buy a new power supply or design one .

a little word on my system

my amp is a bob latino st70 valve amp

http://bob01605.50webs.com/

very nice the detail is amazing, bass response good too for a valve amp

the speakers are audio nirvana super 8's which I put in their 2.8mkii enclosure , these are about a 1m tall and have a effieceny of about 106dB/W, very clear very detailed VERY LOUD lowther replicas.

my cd player at the mo is a marantz cd52mkii but this will be upgraded very shortly to a phillips 950, which will get the lampizator treatment, and be used solely as a transport thanks to my beresford .

all my leads are home made using shielded satelite co-axial (well it has a bandwidth of 300MHz so audio or sp/dif should have no problems(it wipes the floor with some of my other 'dedicated audio ' leads which i payed a bit of money for) ,it also cuts down any magnetic interference).

All in all I can say although the beresford is the cheapest bit of kit in my setup it really really has brought the best out of the other elements and the ability to tinker with it really really has brought a smile to my face !!WOW

thanks
James

[Covenant]

You obvoiusly know what your doing James......
Are you planning to upgrade the power supply? Please keep us informed. With regard to the replacement parts you have fitted what sort of cost for components are you talking about?