Chevron Audio

Active Speaker Crossovers

Most Speakers with passive crossovers can be upgraded by converting them to an active system where the preamp feeds active crossover boards which then feed individual amplifier boards for each driver. This makes life easier for the amplifiers which only handle part of the audio spectrum but most of all allows the amplifiers to control the drive units much more accurately.

My Apogee Stage speakers are now active using a Trimodal amp for the ribbon and Hypex amp for panel, crossover 500Hz Linkwitz-Riley 2nd order.

Systems have also been sold for Yamaha NS1000 & NS10 speakers and also Lema Xeta speakers.


NS1000 amp cables & backplate 2

Getting the best performance from any HiFi component is very much about optimizing the design & component choice. Often commercial & marketing pressures work against this optimizations. Subsequent technical developments also occur from time to time. For these reasons there are many possibilities to upgrade your existing equipment which are more cost effective than buying something new.

We use our experience and expertise to offer upgrades that give value for money improvements.

There are 4 areas where most CD, DVD & SACD Players can benefit from upgrading, Master Clock, Output Stage, Power Supply & Chassis Resonance control. We offer upgrades for these areas in 3 packages and with 2 Master Clock options, so there should be a combination to suit your needs:-




Tentlabs Shunt Regulators

These are used to replace integrated series regulators fitted in the power supplies of most HiFi equipment. They are an effective way of improving sound quality. Find out more at Tentlabs Shunt


Std Clock

The Tentlabs XO clock is used with a very low noise Chevron power supply. The small size and screened construction of the XO clock allows it to be mounted very close to the players clock input circuit. All this gives a much lower jitter clock than standard players resulting in a all round improvement is sound quality.



As with the Std Clock the Tentlabs XO clock is used but run from an even lower noise Chevron power supply which uses its own mains transformer for maximum isolation of power supplies. This is a development from our previous UltraClock2 for even lower noise. Lower noise in the clock power supply means lower jitter from the clock itself


Output Stage

The opamps in the players audio output stage are replaced with very high performance alternatives and circuitry added to bias them into Class A mode. Additional power supply decoupling is added to ensure they work well. We use various types of opamps as suits the particular player. We don’t use adapters to accommodate the different physical designs of opamps because these can degrade performance.


Power Supply & Chassis Control

Additional selected capacitors are added to ensure low noise over a very wide band of frequencies at key points in the players power supplies. Materials are laminated to the inside of the players case to ensure that vibrations are dissipated in a sympathetic manner. Not available as an upgrade on its own.





























Players suitable for the above upgrades include:- Arcam CD62 CD72, Cambridge Audio, Denon, Linn Karik, Marantz CD17 CD63 CD5400, Meridian 208, Myryad, Naim CD3.5, Pioneer DV565 DV575 DV747, Phillips DVD963, Rega Planet, Roksan Kandy, Rotel 965 991, Sony RCD-W3 XB790, Teac VRDS7 VRDS10, Yamaha CDX396 CDX496.


Trichord Dino Phono Preamplifier Upgrade  - I was given a Dino2 to repair with Burson Opamps fitted in place of the standard output opamps. The problem was just with dip-switch settings. I was impressed with the sound quality using my Denon DL-304 MC cartridge. The Dino2 with burson opamps was not far behind my VacuumState FVP5 phono preamp which is a very high performance valve unit designed by the late Allen Wright.

I was also given a Dino1 to upgrade so evaluated various options for the upgrade. The final upgrade consisted of replacing SSM2019’s for THAT1510’s (as used in Dino2), replacing Output opamps (AD744 with discrete class A stage) with LME49710HA’s with class A bias and DC servo, replacing power supply opamps with LT1128. This Dino now sounds better than the Dino2 with burson opamp.

Cost of upgrade for a Dino1 - 170  or for a Dino2 - 70 (Dino2 is just an output opamp change).

Shanling CDT100 - A very special upgrade package is offered for this CD Player. The unmodified player uses many opamp stages to process the analogue signal after the DAC chips mostly filtering ultrasonics. Following the opamps is a valve buffer stage which does not do anything to improve the signal but some people like the effect it has on sound quality.

We could have done a conventional upgrade and replaced the opamps with good ones but even the best will have some negative effect on sound quality. With those nice glowing valves sitting there not doing much the possibility of eliminating all the opamps and just using a valve output stage came to mind. The first test was to take the DAC analogue output direct through a single high quality opamp, this worked very well and established that little ultrasonic filtering was needed, but some gain required in the output stage. The existing valve stage has a gain of one but the circuit could be reconfigured to get the required gain. Several valve circuits were tried and eventually a 2 stage configuration was settled on, the final stage being cathode follower to give a lowish output impedance. The original dual triode valves are used with an uprated HT supply. Ultrasonic filtering is done passively with negligible phase shift in the audio band. There is only one very high quality coupling capacitor in the direct signal path and of course no opamps.

To complete the CDT100 upgrade our standard very low jitter masterclock using the Tentlabs module is installed. 8 additional selected capacitors are also installed to clean up the digital power supplies. Though not rivaling the best players for neutrality and resolution the upgraded player does make music that is enjoyable to listen to and in out opinion is very much better than the standard player.

The upgraded CDT100 has an audio output which is 7dB below red book cd standard (about 0.9V) just turn the volume up a little to allow for this. Best sound is had with the headphone output disconnected but it can be connected if you wish. Optionally a phase switch can be fitted in place of the headphone socket, this works in the digital domain. Some recordings sound slightly better with phase reversed but there is no standard so you have to decide for yourself which phase is best for each disc.

The cost of upgrading the CDT100 is 240 + 30 for the phase switch + return postage.

Creek T43 & Cambridge Audio T500 - we can upgrade these FM Tuners with a new output stage and low noise power supply for 150.

dpa Digital Ltd (Deltec) - We can repair & upgrade many of these products. We can also convert some CD Transports and CD Players to operate as Deltran clock linked transports with most of the dpa DAC’s for 180.

We guarantee the work done for 12 months but can’t guarantee against faults which develop unrelated to the upgrade or repair.

Return delivery is charged at cost.

No need to send money with the equipment this can be sorted out once we have seen the equipment and agreed the work to be done.

Turnaround is normally within 3 weeks but occasionally its longer, we don’t rush things and that includes the all important listening tests.

To send your equipment we suggest one of these  Interlink   Interparcel   Pharos 


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