The CEC TL5 upgrade journey...

[SonicArt]

As some in SNA would know, I have been involved with CEC products since the late 90's, and imported quite a lot of transports and dacs through the 2000's... Modifications have always been something I enjoy looking into, and I have done many machines over the years from the original TL1 & TL5100 series right through the TL51 series and now the TL5.

 

I had a customer from NZ wanting to upgrade his TL5, there was the option of removing the power supply and servo board, antistatic bagging them and sending them over, but he was not comfortable pulling the boards so chose to send the whole machine. While I have had a few TL5's I had not upgraded any yet, so this one was going to be the first.

 

The TL5 is quite bare bones inside, comparing some of its sections to the TL51 series we can see things like the power supply have been minimised somewhat, my guess is with the moving of production back to Japan, they need to be careful with costs in the building of the machines, whilst maintaining reasonable performance.

 

The Servo board in the TL5 is more populated, caps and some regulation appears to have been put on the servo board rather than the separate pwr supply board. They are using a standard rubycon cap throughout, its a decent model of cap but nothing special, very cheap to purchase in bulk. The initial rectification in the TL5 is two simple diode bridges, no snubber caps across the diodes unlike the TL51 series which has snubbers across all diodes.

 

The sound of the CEC TL5 is good, its quite balanced top to bottom, but it does lack some fine detail, and the midrange is a little digital, glassy compared to other hi-end transports, detracting from its otherwise excellent performance. Having improved on this in other machines in the past, I felt these shortcomings could be improved upon.

 

First up the power supply board. it runs two main rectifier circuits feeding a single cap each, there are surface mount bypass caps across the main caps. Comparing the TL5 to the TL2N power supply we can see the boards appear to be the same design, just different print in order to add more caps into the TL2N circuit.

 

I chose to increase capacitance size for the primary caps, and my choice is Panasonic FC, a very good quality low ESR hi ripple current cap (for its size), I also added snubbers across the rectifiers underneath the board, and removed the bypass caps from the circuit as I dont feel the pana caps benefit from these.

After the regulators I like to use a more audio grade capacitor, Nichicon Fine Gold Audio caps are used, I have had good success with these caps after regulation, they seem to reduce the noise floor where you end up with a blacker background, allowing more of the micro detail to emerge, this makes instruments sound more realistic, more natural decay.

 

Once the supply is done its refitted and the machine run for a few hours to settle the caps in, then I put it in the rack and ran it against a stock standard TL5. Improvements were noticed in the blackness of the background, instruments had a more natural sound, more detail in their reproduction. Midrange was improved slightly.

Next up was the servo board, it runs the same basic rubycon caps, I replaced all except one non essential cap with Fine Gold Audio caps, higher voltage as thats what I keep bulk of in the most popular values. I know there is talk across DIY forums about the benefits of using higher voltage caps, larger can/internals, less stressed in circuit, as the cost difference between 25v and 50v is minimal I choose to bulk stock the 50v.

 

Servo board caps were replaced and the pressed brass RCA socket was removed from the board, a Cardas silver rhodium plated copper RCA was fitted with silver link wires. Back into the machine and it was again run for a few hours and then compared to the stock out of the box machine.

The midrange was improved, more natural, it wasnt super warm or forward, but the glassiness was gone, and there is more micro detail thanks to a much blacker background. Sound stage is wider and a little more 3D. Instruments sound more 'real' with better micro detail in the notes, more natural decay, its that feeling you get inside when the music sounds more relaxed and realistic. Bass is more detailed, you feel the instrument more and not just the noise its making.

 

Last thing to do, optional but I think with a machine of this level its a nice addition, is decent legs! The plastic molded feet on the TL5 are basically the same as the ones that came with the TL51 series and TL5100 series!  Not really in keeping with the hi-end pretensions of this transport, luckily I had already designed replacements for the TL51 series, they use the same thread and sizing, so I machined up a set of my Alloy & delrin feet and popped 4mm bolts into the holes from the inside of the machine, they stick out about half an inch giving enough thread for the alloy foot and delrin footer to be screwed on.

The Delrin provides a hi frequency mechanical filter, while the solid alloy feet couple to the chassis. You can also level the drive with the footers, as they should not be screwed in tight anyway.

 

The machine looks quite nice on its new legs, and sounds very good, the owner received it back last week and has been running it in more, his reports are positive, it is more musical and detailed than his Naim transport, the midrange on the Naim appears slightly warmer, but I feel the CEC is flatter across the frequency range and doesn't accentuate any specific areas. he commented that "you feel more of the musical performance, one of those subtleties that makes a big difference".

 

Hopefully he will come onto the forum and share his thoughts with us all!

 

Edited April 26 by SonicArt