Very Important Maintenance/Options

We want to make sure that you get a long service life out of your component. We do a number of ‘unseen’ tasks when we modify your audio component such as:

• Inspect fuses for failure, discoloration indicating near failure(bad resulting sound) …..we replace the offenders
• Check each input jack, switches and volume controls(preamps) …… for signal input/output and noise
• Check non-mod parts that might need replacement …..we inform you and request permission to replace/upgrade
• Check over soldering quality even on original factory builds. We have seen soldering issues such as parts which were crimped but not soldered and wave soldered parts that were not heated fully so you get a ‘cold’ joint that ‘works’ for years but not forever…..these are usually corrected for you without mention

These are just some of the checks. Then there are recommended maintenance items, not included with our standard installation charge. In addition these are priced to install with other modifications such as our PA-XX series - these are not stand-alone charges which are higher.

Thermostat switches - two control the three fan speeds and two control overheat shutdown in your DH-500. These have not aged gracefully. Corrosion in the riveted contact posts is a common problem. We are seeing a high failure rate. Think of their age. Some arrive here looking good externally and some not so good. We worry about every one of them given the age. Replacements(4) installed with new in-rush limiting thermistor included in DH-500 for $110, (2) on DH-200/220/XL-280* for $65(thermistor is not standard part with these amps).  Kit parts are available at $12/ea. In addition we provide a small amount of Silicon thermal grease as shown below. These prices are for installation at the time of another modification.

*XL-280/XL-600s are unlikely to need attention at their lesser age but if you want to insure reliability for the long haul it is the same price as the DH-200/220, but XL-600 would be only $85.

Silicon heatsink compound, that white coating, disgusting to work with, between power mosfets and heatsink dries out to nearly dust on aging amps. We ‘repack’ the power mosfets with new high-performance silicon ‘grease’ to restore efficient heat transfer to the heat sinks allowing each individual mosfet transistor to run cooler which is a good thing. DH-500 service is $100, DH-200/220/XL-280 is $75

<<Geez, you don’t really want to mess with this nasty stuff do you, just let us do it.

>>>>>NEW:(picture soon) We have approved a new silicon transistor insulation/heat-transfer pad that we can install with your mod. These are very effective at transferring heat from the power transistor metal body to your heatsink. They are easy to work with. Individual pads can be purchased at $1.50/ea but you still have to remove each transistor and thoroughly clean the transistor and the heatsink to remove all the old white ‘grease’. Let us install those for $55 DH-200/220/XL-280, for  DH-500/XL-600 for $75 <<<<< These prices are for installation at the time of another modification.

DH-500/XL-600 PACKAGE PRICE: If you do both of the above maintenance items for the DH-500 our price is reduced to $199($169 for XL-600) due to need for disassembly in either case. No labor is saved for the smaller Hafler amps so prices are a la carte.

Power Switches - in the Hafler amps have varied from fairly reliable to incendiary, especially in the DH-500. We have selected a silver-plated switch with 22A capacity. That’s a lot if you aren’t a switch techie. It has high ‘in-rush’ current capability for those first few milliseconds as it handles the current to charge large power supply caps via the power transformer. Reliability has been very high over several years as we have used this switch.  The switch is lighted red when powered on. It has a lamp icon on the ‘lighting’ connector lug for kit installers.

Kit: switch with pre-attached UL-Listed spark arrest capacitor and three(3) fast solder-less crimp connectors, illustrated instructions $22, Installed: with another mod $35, REMINDER: This is part of Ultra mod packages.

These prices are for installation at the time of another modification.

The result of all the above is an amp that is ready for many years of additional service.

POWER SUPPLY OPTIONS

>>>>>>>>>>>>Power supply capacitor options are here!<<<<<<<<<<<<<<

The power supply is the beating heart of your power amplifier. It must provide widely varying current outputs to the speaker load which is very reactive in nature, i.e. difficult to drive properly. Only the finest parts providing instantaneous output current over the whole audio band can hope to offer a truly faithful recreation of the amplifier’s input content.

TP-202 TOROIDAL POWER TRANSFORMER

For Hafler DH-200/220, XL-280 or custom project: 

TP-202 - similar to picture at left*, is a potent toroid power transformer with many important features for an audiophile-grade amplifier.

Technology serves sound:

• Out-powers the original old-style transformer, far more efficient
• High efficiency means quick recharge ability - instantaneous, dynamic sound
• High efficiency - barely runs above room temperature
• PREMIUM FEATURE - External magnetic field is very tightly contained by the external metal shield band - minimizes hum/buzz noise
• PREMIUM FEATURE - Internal electrostatic shield between primary and secondary windings bleeds off higher frequency power line noise to ground via that purple wire

Sound:

• You will notice greater heft or air moving ability, more feeling of bass energy in your chest with capable speakers
• The bass line will be more solid and palpable, a dynamic experience closer to reality
• You will experience a better pitch definition or timbre in the bottom, a smoother overall quality becomes evident
• There will be a ‘blacker’, quieter stage background, a rich unraveling of complex passages emerges
• Instruments will seem to "pop out" of a more silent darker background with greater focus and clarity
• Dynamic range is wider at high power levels, but even guitar, flute and subtle background vocals seem more dynamic and focused

TP-202: $139 kit, $199 installed if installed with other modifications. Necessary hardware is included with kit, transformer appearance may vary The TP-202 is rated for 115/230 VAC ‘wall’ voltage, 50/60Hz operation

How to use it: TP-202 can replace the original transformer for a sonic boost appreciated even with efficient speakers. In addition, TP-202 helps you construct a seriously natural sounding power supply with our new Dual-Mono capable PS-220 board, within the chassis of your Hafler DH-200/220 or XL-280.

Installer Notes: You need a power drill to make the center hole for the transformer bolt (supplied). This will require a 1/4"(or slightly larger) hole. DH-200/220 requires that the fuse holders be moved away from the center of the amp, a tiny bit, if you are going to use the original Hafler boards. Our PA-XX series front-end boards have PCB mounted fuses so that this is not an issue if you are installing or have previously installed these terrific circuit boards in your amp, i.e. you remove the fuse holders completely.

TP-500 TOROIDAL POWER TRANSFORMERS

For Hafler DH-500 or custom project:

TP-500 is a pair of 500 Watt toroid power transformers. These transformers will indeed fit when stacked one atop the other. The original transformer was rated at about 680 Watts, so this upgrade to 1000 Watts is significant. Not only that but you can easily fashion a dual-mono power supply with the PS-220/PS-500V2B circuit.

For sound and technical description refer to TP-200 transformer above.

TP-500(pair of 500 Watt toroids) > $249/kit, $299 installed if installed while performing any other significant modification in DH-500. Necessary hardware is included with kit. Transformer appearance may differ from illustration.

How to use it:

• TP-500 can be used with one pair of filter caps, either the stock ones or the LC-500 caps shown below. Both transformers are paralleled for this purpose.
• You can install the TP-500 with the dual-mono PS-500V2B to make a potent, totally dual-mono power supply. Use the PS-500M for Ultra results. You simply connect each power transformer to the separate rectifier/capacitor system on the dual-mono PS-220/500 single PC board.

Installer Notes: You will need a power drill to make the center hole for the transformer bolt (supplied). This will require a 1/4 - 5/16" hole. 

>>>>>>>>>>>>Power supply capacitor options are here!<<<<<<<<<<<<<<

Dual-Mono Power Supply Conversions: Interested in greater separation of individual instruments on the sound stage and greater ability to "hold together" in loud passages? Want a more effortless sound with new found stability and a "locked on" sound? Dual-Mono will provide these benefits and more! With the advent of our PS-220/PS-500 power supply boards these mods are much easier than the old style which was built up with individual parts. 

We install CARDAS Connectors, CMC GOLD RCA jacks, IEC sockets into any amp whether stock or modified. See our "Connector" page for these hi-quality RCA jacks and binding posts!