Mesa/Boogie LoneStar Amplifier owner manual

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DIAGNOSING PRE-AMP TUBE PROBLEMS:

Because your amplifi er is an all tube design, it is quite possible that you will at some point experience minor pre-amp tube noise. Rest assured - this is no cause for alarm and you can take care of the problem yourself in a matter of minutes by simply swapping tubes.

Let us begin by saying; It is a “very good” idea to keep at least a couple of spare pre-amp tubes on hand at all times to insure unin- terrupted performance. These minor pre-amp tube problems can take many forms but can generally be described in two categories: Noise and Microphonics. Noise can be in the form of crackling, sputtering, white noise/hiss and/or hum. Microphonic problems usually appear in the form of a ringing or high pitched squealing that gets worse as the gain or volume is increased thus are more noticeable in the higher gain “HI” modes. Microphonic problems are easily identifi ed because the problem is still present even with the instru- ments’ volume off or unplugged altogether - unlike pick-up feedback which ceases as the instrument is turned down. Microphonic noise is caused by mechanical vibration and shock: think of banging a microphone around and you’ll understand where the word came from.

The best way to approach a pre-amp tube problem is to see if it occurs only in one specifi c mode or channel. This should lead you to the tube needing replacement. Then all that remains is to swap the suspect tube for a known good performer. If you cannot narrow down the trouble to a specifi c mode or channel, the problem may be the small tube that drives the power tubes which is operational in all modes and channels. Though rare, a problem with the driver tube would show up in all aspects of performance - so if you can’t narrow the problem down to being mode or channel specifi c, you may want to try replacing the driver tube. Driver problems generally show themselves in the form of crackling or hum in all modes of performance and/or weak overall output from the amplifi er. Occasion- ally an anemic driver tube will cause the amplifi er to sound fl at and lifeless, but this is somewhat uncommon, as worn power tubes are a more likely suspect for this type of problem.

Sometimes making the diagnosis is more trouble than it’s worth and it’s faster and easier to merely replace the small pre-amp tubes ONE AT A TIME with a replacement known to be good. But MAKE SURE you keep returning the tubes to their original socket until you hit the one that cures the problem.You’ll notice that tubes located nearer to the INPUT jack always sound noisier...but this is because they are at the start of the chain and their noise gets amplifi ed over and over by the tubes that follow. The tube that goes into this “input socket” (usually labeled V1) needs to be the least noisy of the bunch. The tube that goes at the end of the preamp chain - just ahead of the power tubes - can be quite noisy without causing any problem at all. The tubes in your amp have already been located in the most appropriate sockets and this is why you should NEVER pull them all out at once and ALWAYS swap them one at a time. ALWAYS return a perfectly good tube to its original socket. Also it’s a good idea to put the amp on STANDBY when swapping tubes to reduce the heat build up in the tubes themselves and to prevent explosive noises (which can still occur even if you are pulling the tubes away from their sockets gently) from coming through the speaker.

Remember, take your time, be patient and chances are real good that you can fi x your amp yourself by fi nding and replacing the bad tube. It kills us to see someone who has shipped their amp back to us...and all it needed was a simple tube replacement! If you must send back your amp, remove the chassis from the cabinet by unscrewing the four mounting bolts on the bottom top. The chassis then slides back like a drawer and comes out from the back. Remove the big power tubes and mark them according to their location from left to right 1, 2 etc. They need to be wrapped separately with plenty of wadded up newspaper around them and put in a smaller box within the larger carton. Remove the Rectifi er tubes and wrap them also.You can leave the preamp tubes in or remove them and wrap them separately being sure to label their location. (See Tube Task Chart.)

To wrap the chassis, use plenty of tightly wadded up newspaper so there is at least six inches of “crush space” between the chassis and the cardboard box. Bubble wrap also works well, but please DON’T use styrene peanuts - they will shift during transit and get lodged inside your electronics as well as allowing your amp to end up at the bottom of the box unprotected and possibly damaged.

Pre-amp tubes don’t normally wear out as a rule. Therefore, it is not a good idea to change them just for the sake of changing them. If there isn’t a problem - don’t fi x it. If there is no result from your substitutions, it may be possible that you have more than one problematic tube. Though rare, this does happen and though it makes the troubleshooting process a little more intimidating, it is still possible to cure the problem yourself.

NOTE: It is normal to hear a slight metallic ringing sound when tapping on the preamp tubes. As long as the tube does not break into oscillation or start crackling or any other form of bizarre noise, it is considered normal and functional.

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Contents Mesa Boogie Hello from the Tone Farm Front Panel Controls & Features Precautions & Warnings Front View Lone Star Helpful Hints Helpful Hints Front Panel Controls & Features That will be introduced into the circuitDrive / Clean By itself the Gain control has basically three tonal regions Is still passed on to the Middle and Bass controls Become dominantFor further tweaking To dedicate to each of your two channels Lone Star With the Drive bypassed They could be worth their weight in gold someday Rear PanelRear Panel Channel & Solo External Switch Ports Appearance of your Lone Star Stunning resultsRest Area Factory Sample Settings Sample # 6 Barbeque Personal Settings Sheet Setting # Page Page 6L6 More Page Your amp needed biasing Speaker Impedance Matching & HOOK-UP Guide Speaker Impedance Matching & HOOK-UP Guide A resistance on the amplifi erWiring SCHEMES...Amplifier to Speaker Cabinets Wiring SCHEMES...Amplifier to Speaker Cabinets Wiring SCHEMES...Amplifier to Speaker Cabinets 16 Ohm On TRIODES, Pentodes & Irishmen Page Page Rear View Mesa Oogie Spirit of Art in Technology

LoneStar Amplifier specifications

The Mesa/Boogie LoneStar Amplifier is a standout choice for guitarists seeking a high-quality, versatile tube amplifier that excels in both clean and overdriven tones. Designed for performers who require reliability and tonal variety, the LoneStar is a blend of vintage warmth and modern performance, making it ideal for various musical genres, from blues to rock to country.

One of the main features of the LoneStar is its dual-channel configuration, allowing players to toggle between pristine clean tones and rich, dynamic overdrives. Each channel offers independent tone controls, including bass, mid, treble, and presence, enabling precise sound shaping. The amplifier also includes a unique "Boost" feature on the overdrive channel, which provides an additional gain stage for solos or dynamic passages.

The LoneStar is powered by a quartet of EL84 power tubes, which deliver a sweet, harmonically rich output. This choice of tubes contributes to the amp's tonal character; the EL84s are known for their smooth breakup and dynamic response. Additionally, the amplifier can operate in either 30-watt or 15-watt modes, offering flexibility for both stage and studio environments.

A hallmark characteristic of the LoneStar is its use of the "CabClone" technology, which gives players the ability to silently record or practice by sending a speaker-emulated signal directly to a mixing console or recording interface. This innovation means you can achieve high-quality recordings without the need for a mic'd cabinet.

The amplifier also features a rugged design, with a sturdy chassis and durable tolex covering, ensuring it withstands the rigors of touring. Its aesthetic appeal, paired with its functional controls and footswitch capabilities, makes it a favorite among professional musicians.

With its distinctive tone, versatility, and advanced features, the Mesa/Boogie LoneStar Amplifier has established itself as a modern classic in the amplification world. Whether you are seeking lush clean sounds, soaring leads, or earthy mid-range overdrive, the LoneStar provides all the tools you need to shape your signature sound effectively. For players who appreciate quality craftsmanship and performance, this amplifier is an investment that pays dividends in tonal richness and reliability.