Modding/tweaking my system


Hi all

I thought I would start this thread almost like a diary.

After living with my system for 12 years, purchased 2nd hand, i find myself wanting to see if i can improve on the sound.

I tried modding a Marantz cd67 player years ago with some success then went too far and wrecked it.

The system is 

Rotel RCD02 cd

Cambridge Audio Dacmagic

RC03pre amp

2 RB03 power amps running as mono blocks

PBC FB1

The first thing I wanted to do was tame the overly bright high end by modding the PMCs to + after years of searching I finally found the crossover layout bought the parts and set about the mods.

1st impressions are the highs are tamed however I have 1 speaker that "sounds" louder than the other, more on that later.

I bought the Dacmagic el-cheapo without the box or instructions. I recently downloaded the instructions and realised the Spdif requires the use of a 75ohm digital cable, I've been using a standard RCA all these years.

The room, HiFi and speaker placement are far from optimal but it is was it is and cannot be changed.

I noted I can feel the CD chassis vibrating with music at reasonable levels so that needs a change.

The overall voicing of the system I would describe as slightly forward with a muddy mid range.

It's the highs and mids I'm looking to resolve.

 

notdeadyet

All good advice thus far. You're going to learn a lot about different damping properties with some of these experiments. Far too many materials over damp, using damping is not the way to tame brightness, Brightness is symptom of something wrong upstream, usually inherent to components and/or parts within components. Need to fix this prior to damping experiments.

 

You're ideas about modding cd player are more on right track. Re-clocking may be problematic, likely present clock circuit won't support clock upgrade. Op amp upgrade may be beneficial, research your op amps, make sure its compatible op amp. Coupling caps good place to start. Discrete voltage regulators can be another nice upgrade. Keep in mind if you're novice, may damage cd player beyond repair if you make mistakes.

 

Not sure you're in position for upgrades in equipment, but that would be of greater benefit than mods. However, if you're intent on mods and learning what they can offer, you're on right track.

The trick with Nobsound, most components will only need 2 to 4 springs per footer, and some only 3 not 4. This leaves you with enough springs to do 2 components per set of 4. Springs fit perfectly into. 1/4" hole. So with a 1/4" drill bit and some wood, MDF, acrylic or whatever you can make your own.

Easily the bargain tweak of the century.

Yes it is very easy to over damp and dull the sound. All these things go a little at a time. Evaluate each step. When something sounds better, listen for what it made worse. Because usually there is a tradeoff with a lot of this stuff. Somewhere. The trick is to avoid using so much that the negatives don't start to outweigh the positives.

After a bit of an extended listen I can't say sorborthane hemispheres have changed anything at all.

I don't know a great deal about internal workings of cd players but it struck me the idea of swapping op-amps and caps is a non starter.

As I'm using an external dac surely the signal for sprig is being taken prior to those components within the player itself?

If correct that makes me think the op-amp and cap mod would need to be the DacMagic and the clock on the player? I'm also guessing the dac also utilises a clock? Would they both need to be done to have a significant gain?

Maybe I should focus on power supplies with the aim of cleaning everything up prior to the clock signal?

I am not in a position to fork out for separate linear supplies as they appear to be quite pricy.

Has anyone hear of gains being made by replacing a wall wart for say a larger amperage laptop type supply or diy shielded  power cables? Both of those can be achieved with relatively low outlay.

I can live with (for the moment) the slightly bright presentation, its the the midrange clarity I'm after which is still a bit muddy on some recordings?

After a bit of messing around with toe in I feel the system is getting there.

I'm now leaning towards the room/placement is likely the main cause for the issues I experience, that combined with the greater detail afforded by the new crossover, tweeter and using the correct cable for S/Pdif.

It seems moving around and messing with placement the sweet spot is just out of reach, something always has to give, overly bright, muddy mids or lack of bass extension. 

I also pulled the networks and checked resistance values which are pretty much even across both.

I did however swap the networks which with a short listen seems to have brought about a bit more balance, I've been finding the right channel much more forward than left despite a rough check with phone db meter app telling me the opposite.

I'll have an extended listen later to see if its just an immediate feeling rather than an actual change

Just a caution that mics in phones can't pick up low frequencies, so those sound meter apps are just measuring mids/highs with some very high notes also cutoff. Still handy, but just take it with a grain of salt. Cheers,

Spencer