The *NOT BORING!* Hi-Fi faff chat and sales

[apache]

ah, so having those fancy magnets of the expences cable really won't do a thing......just more rip off stuff :?

They ain't magnets. Have a read of the link in my post.

The player is an old CD63, which simply sounds almost analogue and silky smooth these days. It's surprising what you can do with some attention to the clock, some studio quality op-amps, a whole load of signal path reduction and decent ultra-low noise PSU design.

 

[greenstiles]

i'd like to learn more about this stuff...i've just bought an old Rotel RCD 965BX to modify as i believe lots modify these players.....i've changed opamps in my headphone amp to older style Burr brown's with great effect...........but i'm a novice when it comes to the guts/internals.....but i know a good sound when i here one..........and a bad sound.....


I used to love turn tables, but some very well reviews tables sound poo, and yet a bit of tweeking to moderate ones made them sing......ie changing tone arm cable etc........

Any tips on tweeking the 965BX to my ears it's sounds a tad bright at the top end standard.

 

[legrandefromage]

Heres a pic of the inside of one the pre-production TAG McLaren Audio AV32R processors. These got better every software release and made for excellent 2 channel pre-amps.

Cost to manufacture was around £937, retail was £2300 to £3000 depending on options.

DSP was from Analog Devices 32bit SHARC 21065L chipset.

Most expensive part was the Siemens microcontroller for controlling other units and integrating into multiroom systems. You could also update the software to allow for the addition of new surround formats. These units could be upgraded from Dolby Pro-Logic to Pro-Logic II - this added stereo surround for analog inputs - a very important upgrade back in 2002.

The PCB was assembled at the same facilities as the Formula 1 teams' electronics so was at a very high standard.

Ferrite is located under the heatshrink just before the mains plug.

I was led to believe that this particular unit has a different DAC to production models but I cannot be sure. It does have BNC connections which (from memory!) are the 'proper' way of connecting S/PDIF 75 Ohm.

More info: http://www.iaguk.co.uk/tag/av32r_main.htm

Upgraded model:

 

[apache]

I find most lower priced CD players sound a little bright / harsh. This can be down to a number of things, but is a definite symptom of a jittery / noisy clock. This is often because manufacturing costs and ease of assembly dictate compromises in board layout and simplicity of power supplies.

You'll often find the clock PSU is simply the digital circuitry PSU, which on cheap CD players is also derived from the same source as the analogue PSU. A separate regulated supply with its own rectification and reservoir caps can improve things, as can re-jigging the layout of the clock and its components - usually just a crystal and a few resistors / low value caps. On the Marantz, these are spread across around 2" of board, meaning noise induced into the traces from nearby noisy tracks, and even the inductance of the fine tracks connecting the clock components coming into the equation. With care it's possible to bring these components to within mm of the DAC and then encapsulate them. These are the sorts of things I've been experimenting with.

Tell you something though, jitter is a bugger to measure accurately. Even with the eye-wateringly expensive test kit I have at my disposal!

That TAG kit does look nicely made. I like the addition of the PCB ground plane on the analogue circuitry - though all that digital gubbins must have made for a noisy RF environment inside the box...

 

[legrandefromage]

The AV32R and DVD32R had the pretty unique two cable connection, one sent the digital and the other the clocking information. That and a lead loaded transport led to very, very low jitter.

The only other company at the time to use this, from memory, was DCS.

 

[apache]

The AV32R and DVD32R had the pretty unique two cable connection, one sent the digital and the other the clocking information. That and a lead loaded transport led to very, very low jitter.

The only other company at the time to use this, from memory, was DCS.

Mmmm, always a good idea to use a single master clock and reclock it in the slave components rather than trying to sync multiple ones - bound to end in tears.

 

[legrandefromage]

The AV32R and DVD32R had the pretty unique two cable connection, one sent the digital and the other the clocking information. That and a lead loaded transport led to very, very low jitter.

The only other company at the time to use this, from memory, was DCS.

Mmmm, always a good idea to use a single master clock and reclock it in the slave components rather than trying to sync multiple ones - bound to end in tears.

Dont forget expense - The DCS transport and DAC were very expensive even when compared to TMA's products.

 

[apache]

If anyone fancies a crack at turning a sows ear into a silk purse...

http://www.ebay.co.uk/itm/marantz-cd-pl ... 500wt_1414

Well, thats not fair really. The original CD63 isn't a sows ear. It's pretty decent straight out of the box. A CD53 will do as well, in fact is probably a better base to build from, because some of the mods involve removing stuff before improvement, and a 53 already has some of that stuff not fitted. Less is more in this instance!

Holy crap!!! Just found this. Seems people are already charging stoooopid money to do stuff that's not beyond someone handy with a soldering iron!

http://www.ebay.co.uk/itm/Marantz-CD-63 ... _940wt_906

 

[hamster]

Any thoughts on a CD 50? I had always understood that it was worth it as it has the fabled TDA1541 in it...

 

[apache]

As it 'appens, I have a PDF of the schematics for that. It's quite similar to the CD53 I was talking about, so yes, it will respond well to mods.

The filter and O/P op amps are relatively low grade by todays standards, the regulators are relatively noisy 78 / 79 series fixed voltage types, there are mute circuits which could be removed etc.

Have you got one, as you could go to town on it!?