| FREQUENTLY ASKED QUESTIONS | ||||||||||||||||||||||
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1. How long do tubes last?
On average, tubes last 3000 to 5000 hours. For power tubes, wear is highly dependent on how loud the music is being played and the speaker's impedance characteristics. 2. When is it time to change a tube? Tubes slowly wear out any time that they are in use. Like a light bulb, they gradually lose their performance until they suddenly fail. If the frequency extension and dynamics that they once had are no longer there, then they have worn out. When preamp tubes fail, they make hissing or crackling noises. If these sounds are coming from one channel, removing the tubes from one channel and installing them the other determines if a tube is bad. If the noise comes out of the other speaker after the tubes are switched, then one or more tubes need to be replaced. If a bad tube is in a power amp, it may become very hot and bright and the fuse will usually blow. 3. How reliable are tube testers? Tube testers, depending on model and within limits, can give a general picture of certain characteristics, however, they are not the be all and end all. Quoting from the RCA Receiving Tube Manual, "The tube tester cannot be looked at as a final authority in determining whether or not a tube is satisfactory. An actual operating test in the application will give the best possible indication of a tube's worth." Even with five various testers including a Tektronix curve tracer on hand, Sonic Frontiers has always tested, matched, and burned in replacement tubes in the SFI or Anthem model that the tubes are destined for. 4. Do the tubes wear out more quickly if they are left in standby mode? In standby mode, only the filaments remain activated to keep the tubes heated. Tubes last longer if they are already hot before the main power supply is applied. The main power switch in a preamp, CD player, or DAC should be turned off when the equipment is not in use for more than one week. Power amps should not be left in standby mode since they wear out at a greater rate than preamp tubes while in operation. Standby in a power amp should be used for approximately five minutes before use. 5. What is the benefit of matching tubes? Four reasons to match power tubes are: one, to increase tube life; two, to lower harmonic distortion; three, to reduce hum; and four, to preserve the life of the output transformer. Matching preamp tubes provides equal gain in both channels. As well, noisy, microphonic, and dead tubes can be rejected at the same time that matching and burn-in is performed. 6. Can the 6N1P be used as a substitute for the 6922? Tube substitutions that can be used for the 6922 are any low-noise, non-microphonic 6DJ8, ECC88, E88CC, and 7308. The 6N1P requires twice the filament current and is not recommended. 7. How is the SFL-2 recalibrated when replacement tubes are installed? When ordering tubes, please specify the equipment that they are for. In the case of an SFL-2, a diagram will be included with the set of tubes for setting the phase balance controls. 8. What happens when a 4 ohm speaker is connected to an amp with 8 ohm outputs? An impedance mismatch results in greater tube wear and more strain on the power supply and output transformer. All Sonic Frontiers and Anthem tube amplifiers can be configured to match various speaker loads. Instructions on how to change the output transformer impedance can be found at owner's manual . 9. What kind of interconnect and speaker cables are recommended? The way a cable sounds depends on the whole system as well as the length, impedance, and capacitance of the cable. Many good cables are available and most dealers can provide samples for home auditioning. Room acoustics also play a role in determining which cable sounds best in a given system. 10. Which connection is better, balanced or single-ended? Balanced operation offers better noise rejection and lower distortion than single-ended, provided that the circuit design is balanced throughout. All Sonic Frontiers components with balanced connections have fully balanced topology from input to output. 11. How does the parts upgrade for the SFCD-1 and Processor 3 improve the sound? The higher quality parts make improvements in clarity and soundstage width and depth with more precise imaging. Dynamics are not affected. The tube choice can affect the liquidity of the sound but better passive components such as resistors, capacitors, wire and connectors keep the signal closer to the original. 12. Is a parts upgrade available for amps and preamps? Over time, as parts combinations are tried and tested, parts upgrades for amps and preamps will appear at upgrades. 13. Why is the CD player no longer reading discs? The most common reason a cd player does not accept a disc is because dust or tobacco smoke has settled on the lens. As a result, the light cannot pass from the laser to the disc and the lens must be cleaned. There are two ways to clean the laser's plastic head. The easier way is to use a CD-type lens cleaner according to the manufacturer's instructions. The more reliable but more delicate way is to clean the lens with a small amount of alcohol or water and a cotton swab. The lens is located directly underneath the magnetic clamp. Contact cleaners should not be used since they are not safe on most plastics, including the lens. |
14. Why is there a loud pop when the preamp is turned off? When the preamp is switched off, it could send a voltage spike to the power amp. If the amp is on, it will amplify the spike and send it to the speakers. The power amp should always be off while the preamp is switched either on or off to prevent damage to the amp or speakers. 15. Is there something wrong if the red LED inside is glowing? There is nothing wrong. Normal operation is indicated if one or more LEDs are glowing inside a Line 1, Line 2, Anthem preamp, or Anthem CD-1. 16. How does the SSP function work? SSP (surround sound processor loop) completely bypasses the preamp circuit by connecting the SSP input directly to the preamp output. If a 2 channel amp is kept in the system, both the surround sound processor and the preamp can be used without having to reconnect anything when switching between music listening and movie watching. The center, rear, and subwoofer channel outputs from the processor go directly to a three channel power amp, but the main left and right outputs from the processor plug into the SSP input on the preamp. 17. Why is there a lot of buzz / hum only in SSP mode? In SSP mode the preamp is completely bypassed. If no problem exists in regular mode, then the hum is originating from another source. In home theater setups, ground loops are a common problem. The loop can be traced by unplugging the components one at a time until the hum disappears. The power cords should not be plugged back into the same outlets. If the buzz disappears only when cable TV is disconnected, the cable company should be contacted. 18. Why does the sound from the main speakers disappear when the subwoofer is connected? Some models of powered subwoofers mute their inputs when not in use by shorting the input jack. If it is connected to a second output of the 2-channel preamp while it is off, the sound that is supposed to go to the 2-channel power amp is also shorted. If this is the case, the subwoofer should either be left on, or disconnected from the preamp when playing 2-channel material such as phono or cd. 19. How is cartridge loading set in the Phono 1, SFP-1, SFP-1 Signature, or Anthem Pre-1 and Pre-1P? The cartridge manufacturer specifies a resistive and a capacitive load impedance. If the recommended resistive load is approximately 47000 ohms, then the Rload socket can be left empty. If the recommended load is less than 47000 ohms, a load-matching resistor can be soldered into the Rload socket. A 1/4 watt metal film resistor with 1% tolerance should be used. The following formula is used to calculate Rload: Rload = Zin * Zrec / (Zin - Zrec) where: Zin = phono preamp input impedance Zrec = recommended load impedance To put it in words, the product of Zin and Zrec is divided by the difference between Zin and Zrec. Note that although it appears similar, this is not the formula used to calculate the total impedance of two parallel impedances. This is because the total impedance (Zin) is already known. The values of Zin are as follows: Phono 1: 47500 ohms SFP-1, SFP-1 Signature: 49900 ohms Pre-1, Pre-1P: 47000 ohms Calculating capacitive loading requires that all capacitances are known. This is rarely the case, since the tonearm wire capacitance plays a significant role. Typically, input capacitance at the phono stage is 100 picofarads. The value of the capacitor in the Cload socket is added to this figure. The value of Cload is best left up to the ear. If the high frequencies are too loud, a capacitor can be soldered into the Cload socket to bring them down. A polystyrene or polypropylene capacitor should be used. Typical values range from 100 to 300 picofarads (pF) with a maximum voltage of 63V. Further details and examples can be found in the owner's manual download section. 20. Can the gain of the Phono 1 be changed? There are three gain settings for the Phono 1: 62dB, 54dB, and 44dB. Most were set at the factory for 62dB or 54dB. 62dB is recommended for cartridges with less than 0.6mV output, and 44dB is recommended for cartridges with greater than 3mV output. The following is a chart of resistors as they correspond to gain settings:
Non-inductive wirewound resistors should be used for R7 and R8. For best sound metal film resistors should be used for R1, R2, R5, and R6. 21. Is the warranty transferable for used equipment? The warranty is not transferable unless the used piece is purchased from an authorized Sonic Frontiers or Anthem dealer. 22. Can a remote control be added to discontinued Sonic Frontiers and Anthem preamps and integrated amp? The remote control cannot be added. To do so, extensive modifications are required and a conversion is not worthwhile. | |||||||||||||||||||||
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