Q: Is this a solid state amp or digital modeling amp or a hybrid tube preamp /solid state power section?
A: Hell NO! This is an all tube 18 watt @ 5% THD guitar amplifier that uses 12ax7's and 6AQ5 power tubes.
Q: What is THD?
A: THD stands Total harmonic distortion. It is a radio standard measurement for volume before distortion. Many amp companies over bias power tubes in order to market wattages. The PAK is an honest and loud 18 watts.
Q: What are 6aQ5 tubes?
A: They are a 7 pin military grade tube equivalent to a 6v6 in design and operation.
Q: How long will my 6AQ5 tubes last? Where do I get replacements?
A: The NOS 6AQ5/6005W’s that are included in the PAK amp will last almost indefinitely. We have seen life of 5-10 years routinely since we started to use and test these tubes in 2008 with the Reason Bambino. Preamp tubes typically do not “wear” out, the can however become microphonic and need replacement. We at KHAN Audio are of the mindset…. If it’s not broke, don’t fix it!
A: NOS 6AQ5’s are plentiful on ebay or other online sources. We use and ecommend the military 6005 version. Matched pairs are available for $12 + shipping
Q: How do I change the tubes?
A: Allow the amp to discharge for 30 minutes before removing the lid. Carefully wiggle the tip of the tube while separating the base using a small insulated handle screwdriver. Move the tool around the perimeter a few times while wiggling and pulling on the tip. See the website video for a full explanation.
Q: My amp is powering up but not working, now what?
A: Check all the rear panel rocker switches. Make sure none are hanging up between settings.
A: Check settings of the gain and master controls along with the channel selector
Q: Why is it important to match the impedance?
A: In the case of a tube amplifier, the tubes need to see the proper load to operate at the optimum conditions. Any variance from the designed load will result in less power and bandwith, possible damage could occur.
A: Imagine a car with the gas pedal floored, this is like a tube amp with no load attached. The engine will probably blow up, or in the case of a tube amp it will flash arc the output tubes. Now imagine you applied the clutch IN THE APPROPRIATE GEAR and then floored it, now some work is being done. This is like a tube amp with the proper load on it. Now imagine you put it in high gear and the engine is lugging at a low RPM, this is like a tube amp with a very low / incorrect load and could cause current to be high and premature wear of tubes and/or output transformer.
Q: What kind of cabinet do you recommend?
A: The 4x12 cabinet is the preferred cabinet we use for testing and performance. It is truly the industry standard and it is a unique instrument in itself! Greenback speakers will have the smoothest upper mid and high end response with a softer bottom end compression. A 2x12 or 1x12 can also be used depending on the gig and situation. Extremely small 1x12 cabinets do not have enough volume to let the speaker breathe and will result in a choked sound.
Q: How do I obtain service or warranty work?
A: Direct customer support is available through email at firstname.lastname@example.org. Once a problem has been identified KHAN will issue a call tag for the unit to be repaired in house.
Q: What fan setting should I use? Can I turn the fan off?
A: The fan has a low and high setting, either setting will adequately cool the unit. There is no “off” setting for a good reason, the amp will run hot with no fan running. Always take care to space clear above AND below the unit. Air is drawn in through the base and flows across tubes and out the top vents.
Q: Footswitch jack and which type to use?
A: Single channel uses a single button ¼” TS cable. Dual channel uses a 2 button ¼” TRS cable. The standard parallel LED can be connected and will light in accordance with channel and mid boost engagement. CE dist has one that works well - P-H470-LED, P-H471-LED
Q: Why are there no indicators on the knobs?
A: There are indicators on the knobs, they are indicated by the location of the chrome setscrew inset in the body of the knob. This provides visual feedback but maintains a smooth feel in appearance and usage.
Q: What is the difference between the single/dual channel versions?
A: The obvious difference is the channel switching, but both amps have a unique voice. The single is more a warmer bassman type bluesy clean base sound, while the dual starts with a tighter crunchier British flavor to the original American circuit adding in the 2nd channel that goes in to modern modded hi gain territory.
Q: How does the FX loop work? Where in the signal chain?
A: The FX loop is a buffered series loop located after the preamp section. Time based effects like delay and reverbs will benefit from being placed later in the preamp. Gain pedals and fuzzes should be placed in front of the amplifier to blend in the best way.
Q: Do I need a cab to use the line out?
A: The PAK amp has an internal 8 ohm load built in to the amp. Disconnecting the speaker jack is perfectly acceptable and will engage the load resistor. The line out is a balanced ¼” TRS line level output for use to a mixer for FOH and studio applications. It is always active whether the amp is connected to a load or the internal resistor. A ¼” unbalanced cable can also be used with no ill affects.
Q: Can I use a ground lift?
A: Never defeat the ground connection. If hums and buzzes occur in a multiple amp setup, ground lifts may be attempted to quiet the hum, but it may make the situation worse. Always check for voltage potential by touching a metal part (tuner) to the microphone first….
Q: Can I use the line out as a headphone out?
A: No not in this case. The level will not be high enough to hear the headphones.
Q: Can I mount the PAK amp on my pedalboard?
A: YES! You can mount the pak amp on a pedalboard as long as you maintain adequate airflow through the unit. We do not promote the amp as a “pedalboard” amp perse, but it certainly can be used on a pedalboard.
Q: Does it takes pedals well?
A: Yes the PAK amp takes pedals quite well. The overdrive characteristics blend well with all different types of drive pedals.
Q: Does it have a negative feedback loop?
A: YES the amp has a negative feedback loop. When properly used in an amplifier, NFB is used to correct distortions and to tighten the sound. The PAK power amp is based upon classic designs that employ NFB, so very similar behavior is achieved.
Q: How loud is it?
A: The PAK amp is about as loud as a deluxe reverb.
BRIGHT SW – Use with humbucker equipped guitars to put some cut and slice to the sound. Single coils
typically do not need the extra brightness, but by all means try it you might like it! Classic guitar sounds
are full of treble and upper mids, when the power amp is cranked up, more brightness can be tolerated
so always PLAY LOUD!
Mid boost – The mid boost can be used to fatten the single coil pickup for a thick punchy attack. It can
also be used with a gainier sound to pop thru the mix for soloing etc. Along with the bright switch can
really focus and change the mid and high end character of the amp.
Gain master settings – 5 second rule – All amplifiers have a voice and tonality. Some are more effective
at delivering a “guitar” sound with minimal tweaking. The PAK amp falls into that category….tone is
almost preset with knobs at 5 – flavoring will only tilt in one direction or the other but the essence of
the amp stays the same. This is our philosophy of tone here at KHAN audio, it’s the 10 second rule.