CD23 Modifications...

Hififella

Standard Member
Any opinions on the modifications to the cD23 on Ebay by Audiocom which are supposed to improve the "lean upper bass" ? Any views on this supposed problem - is it as pronounced as in the CD72?
 

mcguiganp

Active Member
Any opinions on the modifications to the cD23 on Ebay by Audiocom which are supposed to improve the "lean upper bass" ? Any views on this supposed problem - is it as pronounced as in the CD72?

Hi,

I haven't seen the mods, what do they include? One quick and relatively inexpensive way of improving the your 23 would be to replace the last 2 caps in the output stage with 5uf Auricaps. Apart from that the 23 as you can imagine is a very well built machine. I have the cd72 and have replaced the last 2 caps. Gave better separation all round. To my ears anyway the bass is well in balance.
 

Hififella

Standard Member
Hi the mods are as follows:

"The CD23 is essentially made up of two PCB’s, the main power supply & digital PCB, then the audio circuitry PCB is fixed to an aluminium plate and held upside down on top of the main PCB. Phase 1 of the modifications upgrades the main PCB digital & analogue power supplies, employing Black Gate NX for the analogue power supply. Regulator bypass & local digital de-coupling capacitors are also replaced for Rubycon ZA types.

The OEM master clock is a single transistor discrete design, evidently better than the poor quality CMOS inverter based clocks seen in other CD players regardless of price. We were keen to hear how the Superclock 4 (SC4) would perform in the CD23 and made this upgrade in isolation and listened.

We were keen to hear how the Superclock 4 (SC4) would perform in the CD23 and made this upgrade in isolation and listened. We can report that this new clock improves significantly upon OEM oscillator. Most notable is the increase in sound-stage depth and projection, a more flowing, organic, relaxing sense of the music. There's more detail, truth of pitch & timbre, bass delineation.

Tonally the CD23 looses that degree of hardness, leanness heard in the OEM player, with SC4 the tonal balance has a natural warmth and organic flow which makes listening for longer periods fatigue free. Bass is more sure footed, with added energy and power to ensure that the lower registers are more convincing.

Next we turned our hands to the audio board; regulator bypass & de-coupling bulk electrolytic capacitors are replaced with Black Gate FK & N types. Selected polyester film capacitors in the post DAC analogue stage are replaced with Black Gate NX Hi-Q. The OEM selected op-amps for filter are OP275 and the buffer uses the Burr Brown OPA2134, a 7 year old op-amp designed specifically for audio. The OPA2134 offers mediocre performance, with a laid back, lacklustre sound which tends to soften and veil the sound.

In this final part of the Phase 1 modification we replace the buffer op-amps with the new LM4562 from National Semiconductor. The LM4562 is op-amp to love, if reading spec sheets gets you going then check the excellent 120db PSRR or the vanishing low 0.00003% THD, the 4562 is the closest to no op-amp we have heard in a long time."


I have a CD72 at the moment, not a CD23, and like the big weighty sound, but cant get away from the lean mid - high bass. I note that you have also have a DAC - do you use the CD72 for transport only or also as a stand alone player...?
 

mcguiganp

Active Member
Interesting mods. To be honest if you're handy with a soldering iron you could carry out the mods yourself and probably save a fortune. Be wary of the black gate caps, they have a sound you either love or hate, personally I'm not a fan. To me they are too thin and nasal, exactly the sound you are wanting away from. The op amp replacements are fine but again probably only cost a couple of quid each from RS. If you are going to have a bash yourself consider replacing the power caps with Panasonic FC caps and bypassing with wima cerafines 1uf. Im ny opinion it's the caps and opamps that give a component it's sound flavour. The superclock mod will increase the soundstage and separation. How much are the mods? Burr brown opamps tend toward the warm side if that's what your looking for.

I use my cd72 as a transport going into a modded musical fidelity xdacv3. I am very happy with the sound. Separation, bass and soundstage all improved dramatically through the dac. I had the chance to compare with a friend's cd36 and it was a whisker away from being as good, not as much as the cost difference however.

A dac can be a very cost effective solution but they are difficult to audition. Try and get a listen to a MFxdacv3, it is a very good dac for the money.
 

Timmy C

Distinguished Member
I spotted these mods on ebay too. I'm hoping someone on here will give it a go at some point soon as I'm very interested but have no spare cash at the moment.

I think it was Avondale (or something like that) that used to mod the Alpha 5 player and people used to rave about them so I'm tempted to give it a go sometime.
 

ajhavf

Standard Member
I have these and some further modifications being done at the moment by Audiocom. I'd be happy to relay my experience for others considering sending in their unit.

I decided to go ahead with this as I'm not going to sell the unit and I think it could perform better. Audiocom seem to have a superb reputation concerning complex modification and in particular their upgrade parts.

My main concern is the new stresses the modifications place on the system, also the failure of the transport system. The unit gets warm as it is in stock form.

As to the opamp replacement, perhaps the discrete opamps from Burson are the best choice ?
 

mcguiganp

Active Member
I have these and some further modifications being done at the moment by Audiocom. I'd be happy to relay my experience for others considering sending in their unit.

I decided to go ahead with this as I'm not going to sell the unit and I think it could perform better. Audiocom seem to have a superb reputation concerning complex modification and in particular their upgrade parts.

My main concern is the new stresses the modifications place on the system, also the failure of the transport system. The unit gets warm as it is in stock form.

As to the opamp replacement, perhaps the discrete opamps from Burson are the best choice ?

The burson op-amps are supposedly superb. I considered using them in a recent mod job but thought they were a tad pricey. Settled for BB op2604's instead :smashin:
 

ajhavf

Standard Member
The burson op-amps are supposedly superb. I considered using them in a recent mod job but thought they were a tad pricey. Settled for BB op2604's instead :smashin:

They are indeed not cheap, must be used wisely.

A situation where both the Burson voltage super regulators and the discrete opamps were purchased, unfortunately the opamp failed to work properly, the discrete opamps required a little too much power for the unit to cope with (this is a fairly confident diagnosis, but not certain). The project remains in limbo.

I thought as Audiocom specify the new LM4562 opamp, which looks to have mighty impressive spec's, maybe discrete opamps ala Burson are too power hungry for the implementation in the CD23T or, not worthwhile given the new opamp's performance. Both opamps in the stock CD23T are candidates for replacement by the Burson discrete opamp unit, disregarding the specific implementation in a CD23T. I'm not sure as to the exact situation, but if I could choose without problems, I'd have the Burson discrete opamps installed. I can't find a discrete opamp made by Audiocom.
 

vistisen

Active Member
I found the following on a certain auction place:

http://cgi.ebay.co.uk/ARCAM-FMJ-CD2...40QQihZ020QQcategoryZ3272QQrdZ1QQcmdZViewItem

I hope I'm not breaking any rules by including the link.

Does anyone have any experience with this modification? I love my CD23T's sound. But if it can get even better...

I have had a look at their website and can not find modifications of ARCAM on it. This auction description is quite detailed, is there someone from Arcam who would care to comment? are the new components not in the CD23 because of price considerations, or are they newer?
 

Dankeech

Member
I found the following on a certain auction place:

http://cgi.ebay.co.uk/ARCAM-FMJ-CD2...40QQihZ020QQcategoryZ3272QQrdZ1QQcmdZViewItem

I hope I'm not breaking any rules by including the link.

Does anyone have any experience with this modification? I love my CD23T's sound. But if it can get even better...

I have had a look at their website and can not find modifications of ARCAM on it. This auction description is quite detailed, is there someone from Arcam who would care to comment? are the new components not in the CD23 because of price considerations, or are they newer?

Hi Vistisen,
If it had been your own auction -no, but the link's there for a good reason on this thread so all is fine:)
I'm also interested in what difference mods can make.

Dan.
 

mikex

Standard Member
Modifications can improve the CD players audio output by more accurately tracking the bitstream (better clock accuracy) and improving smoothness of power supplies (noisy AC is the worst supply possible).

Another option is to use an external higher quality DAC. For instance the DAC within an FMJ A22 + DAVE processor board is very high quality and improves greatly on the detail available from the CD23 dCS ring DAC. To make the most of this try biamping to really bring out the detail provided by the superior DAC.

IMHO

Mikex
 

Dankeech

Member
All,
As Ajhavf rightly pointed out, there's already a thread covering vistisen's query, so I've merged the 2 threads together to make things easier and tidier. So the same subject can be discussed on one thread:lesson:

Enjoy the rest of Sunday:)

Dan.
 

ajhavf

Standard Member
My player has arrived back, I'm listening and so far I'm impressed.

I'll try and give a detailed description of the new sound soon.
 

ajhavf

Standard Member
As the burn in continues subtle changes are occurring. At 120 hours of playtime the major burn in changes ought to have settled, I'm at about 75 hours.

My unit has undergone Phase 2 modification. Not yet listed online, so you will have to estimate the Phase 1 value.

Audiocom Ultraclock installed.
DCT of Ultraclock and RingDAC pcb. These were carried out by Frozen Solid Audio.
Some further power supply refinements.

I can say the sound coming from this machine is awesome. Very smooth, highly detailed subtle nuances and very musical sounding. The flow of the sound is brilliant, it's liquid smooth and absolutely no harshness to it. In essence the stock sound of CD23T undergoes extensive refinement.

This kind of modification is not for everyone, you will need a high resolution system to put this machine into, otherwise be assured you will not gain the maximum benefit that is on offer. Note also I think that this modification pushes the transport device to the maximum.

I hope this helps people considering modifying their original equipment.
 

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