Getting Started: Some FAQ

To get started we need to know exactly what you have. What model and what Generation power module is installed? Q: “How can I tell which generation board I have in my subwoofer?” A: One cannot tell by the serial number or just by looking at the assembled subwoofer alone. The power module must be removed to identify whether a Generation 1 or Generation 2 circuit board is installed. Click here to learn how to identify which generation board is installed in your Entec subwoofer. Q: “Can I just get my subwoofer repaired or do I have to do a full overhaul?” A: While we prefer to do full overhauls & refurbishments in order to ensure longevity and performance as well as preserve the unique pedigree of your Entec subwoofer, we understand that not all budgets allow for this level of attention. Entec Subwoofer Service would be happy to evaluate, advise, and then perform only the repair(s) needed; keeping you, the owner, in the loop and in control. Q: “Shipping is expensive. Do I need to send the entire subwoofer?” A: It all depends upon which circuit board is installed in your Entec subwoofer. Original Generation 1 circuit boards require that they be “married” to the driver & servo coil they’ll be working with as mounted in the cabinet. This is not something most folks can do on their own or be talked through. Entec upgraded the SW series subwoofers they repaired by replacing the old manually-adjusted servo board (Generation 1) with a new auto-adjusting one (Generation 2). If your SW has this later Generation 2 board we can work with the power module alone, just like the Generation 2 LF series. However, the drawback is we won’t be able to fully test your subwoofer with only your power module and our test bed. When we receive the entire subwoofer we remove and test each driver for performance as compared to Entec’s original driver response curve. Any deficient drivers are repaired at that time. Once your power module is refurbished, married to your drivers & servo coil, and tested as a unit, it’ll be ready to return home to you. Back to top

Refurbishment / Overhaul:

A description of the work performed on Generation 1 and Generation 2 power modules in for refurbishment: Capacitors: Most power modules that come through the shop have had several of the aluminum lytic capacitors test bad yet the subwoofer was still “working”. Whether they test good or bad, being 20+ years old is reason enough for all of them to be replaced with audiophile grade capacitor replacements and that’s what JRS does. Carbon Resistors: There are several old carbon type resistors on the Gen 1 boards and their age shows physically as well as value-wise. On full refurbishments, all carbon resistors are replaced with 1% non-inductive wirewound types of equivalent or higher wattage value with the idea of low noise, longevity, and performance in mind. Semiconductors: While the Generation 1 series usually doesn’t fall victim to heat damage like the Generation 2 boards, on full refurbishments many of the old transistors, voltage regulators, and integrated circuits may be replaced. New output transistors, matched for gain, may be installed. Also, as an option, the old bridge rectifier block is removed and updated with a new Fast Recovery Epitaxial Diode (FRED) bridge rectifier. When all is said and done, hundreds of non-solder, de-solder and re-solder connections may be performed on your unit. Due to the heat issue on Generation 2 power modules, potentially overstressed integrated circuits and transistors are replaced as a precaution against future failure. As stated elsewhere on this site, all board mounted power supply semiconductors (as well as the other p.s. components) are replaced as well as the JRS heat mod being incorporated. Wiring: Depending on what’s currently installed in your Entec, the original wiring from the power capacitors to the circuit board as well as from the bridge rectifier may be replaced with a higher quality wire. To try to reduce 50/60Hz hum as much as possible, wiring cables are replaced with shielded cabling as needed. Adjustment Pots: Standard for full overhauls or a suggested option for repairs, the four ¾ turn notch filter pots on Gen 1 boards are removed and replaced with high precision, multi-turn, sealed potentiometers, carefully adjusted for their notch filter frequency, and locked in their adjusted position. Please do not…as in NEVER adjust these pots on your own unless you have the proper equipment. Switches: The source selector switch & active crossover selector switch inside the Gen 2 modules along with the high-pass crossover and phase select switches in the external Crossover Module get dirty and intermittent over the years. For example, one set of Entec modules that were in for repair revealed intermittent signal to the left sub with normal signal to the right due to a dirty Phase switch in the Crossover Module. At the same time, the active crossover switch inside the right sub was malfunctioning to the point of making the crossover operate at 180Hz even though 100Hz was selected in both it and its sister subwoofer; no wonder things didn’t sound right! These switches are disassembled, cleaned, reassembled, and checked while your unit is in for refurbishment. Since these switches can be (are) such a problem it is required that both the Crossover Module and 4 pin XLR interconnects be included with your Power Modules when sent. As an additional cost item, these switches can be changed to more reliable components upon customer request. Other Repairs: Besides the normal updating that comprises a JRS refurbishment, it is possible that other systems (servo, amplifier(s), active filter, etc.) might also need repair. These areas are usually discovered upon initial incoming inspection or during the post mod checkout and if necessary, will be quoted for repair over and above your unit’s modification(s). Most of the time though the normal refurbishment process automatically takes care of these issues without incurring additional cost to you. Examples of non-included repairs would be servo coil repair / replacment, driver repair or replacement, IEC connector replacment, broken, wrong type, or missing switches, etc. Back to top

Shipping:

If you live in the Seattle / Tacoma area you can arrange to bring your fully assembled subs to the shop for their refurbishment. However, if you’re further away, depending upon your Generation of power module circuit board (Gen 1 or Gen 2) it might be possible to simply remove the Power Modules from the subs and ship them to JRS. Please make sure you mark the wiring for re-installation as well as note the orientation of the small 2 pin servo connection before you unplug it (open side faces in or open side faces out). This will be very important when it comes time to reassemble your refurbished unit. Click here to learn the differences between Generation 1 and Generation 2 circuit boards. Please do not pack your equipment in Styrofoam peanuts. I jokingly say that we’ll charge $100 for every peanut that delightfully explodes out of the box which I then have to chase around and pick up. But in all seriousness, the Power Modules are too heavy to trust to peanut packing or simple bubble wrapping. If it moves and shifts in the box after you pack it, it’s not acceptable. JRS will not be responsible for any item(s) received that are improperly packed. Shipping guys hate heavy packages that move and shift and they’re more inclined to drop them. Take the time to correctly box and pack your units. If you need instructions on how to do this we can offer some guidance. For power modules alone, UPS or FedEx Ground have both performed just fine when units are properly packed. For planning purposes you’ll be shipping to zip code: 98335. For shipment of the entire speaker an independent shipper is often the best way to go. One suggestion would be R+L Carriers. Please note: All shipping of units and parts are at the owner’s expense. As regards refurbishments and repairs, actual parts shipping costs are charged with zero mark-up and are best-guess estimated during quotation. Unless otherwise requested, parts shipment methods will be 2 or 3 day delivery with tracking. JRS will not be responsible for parts shipment methods that do not include shipment tracking. Back to top

Drivers:

Unfortunately, the manufacturer who offered new drivers in 2017 is no longer providing these and therefore re- foaming and re-coning services are the best and often only way to go. For Generation-1 drivers requiring added foil doped onto the cone, this service can be provided. If you’re on the east coast of the United States your best and fastest source for driver repair is Millersound located in Lansdale, PA. On the west coast of the U.S. we recommend The Loudspeaker Store located in Kent, WA. Entec Subwoofer Service has worked well with both of these shops and can confidently recommend their services. Servo Sense Coils & Brackets: We don’t know why but from time to time an Entec sub will show up with the servo sense coil broken off and missing. This coil is mounted behind the bracket that sits over and in front of the driver whose position and acceleration is being monitored by the circuitry. It is the heart of an Entec and without it your subwoofer will likely be damaged severely. So, if you’re wondering “can I get rid of that coil thing in front of the driver?”, the answer is a resounding “NO!” E.S.S. has these coils on hand but note that you’ll need to send the entire subwoofer to have this replaced as the sense coil and the driver it sits in front of must be “married” for physical and electrical zero. Back to top

Additional Information

Return of old parts: Unless otherwise requested old parts are discarded. If you want your old parts returned please let JRS know at the beginning of your project. Additional packaging and shipping costs may be involved.

Guarantee:

Unless otherwise specified, JRS Engineering warrants the units worked on for a period of one year for parts and 90 days for labor beginning the day your unit(s) are shipped back to you. The warranty covers only the work performed. If a warranty situation arises, JRS Engineering reserves the sole right to determine warranty eligibility and responsibility with consideration given to such causes as abuse / misuse, modification / repair by others, and component failures in areas not related to the original repair, modification, or upgrade. Damage to other external components connected to your Entec system is not covered. Unless otherwise agreed upon, inbound and outbound shipping for warranty items is the owner’s responsibility.

Scheduling:

Refurbishments and repairs are done by appointment only. As these are audiophile level components and often a bit individualized JRS purposely allows only one (maximum two) pair of Entecs in the shop at a time. This allows for undivided attention to your project and a timely completion. This is not an assembly line; individual testing and burn-in takes time and shop space. JRS tests each refurbished power module for a minimum of 24 hours continuous idle and then many hours more with a music source. Know that from start to finish, not including shipping from or to you, a full refurbishment can take as much as six weeks; sometimes less, sometimes more. Be patient, please. Pictures: It would be very helpful to include good quality pictures of your sub’s drivers as well as pictures of the removed power module boards (top and bottom). Tell us if the unit works. Is there hum or oscillation with no music signal applied? Does the sub have a “motor boat” type oscillation when turned on? Are there static or popping noises, etc.? A lot can be answered from a few pictures and emails. See some examples of helpful pictures we’re looking for on the Contact page. To begin the conversation about your Entec repair, refurbishment, or overhaul please contact JRS at: Service@jrseng.com.