How about the warranty?
Meyer Musical instruments (“Meyer-Amps”) warrants its amplifiers to be free from defects in materials and workmanship (subject to the terms set forth below) for a period of five (5) years from the date of purchase. Speakers for a period of one (1) year from the date of purchase.
To obtain Warranty service, please contact Meyer-Amps for repair. Please call Meyer-Amps at +31 24 329 67 39 or email at info@meyer-amps.nl for instructions. You will need to ship this product in either its original packaging or packaging affording an equal degree of protection. Return shipping costs to Meyer-Amps is the responsibility of the purchaser.
Proof of purchase in the form of a bill of sale or receipted invoice, which is evidence that this product is within the Warranty period, must be presented or included to obtain Warranty service.
This Warranty does not cover cosmetic damage or damage due to misuse, abuse, negligence, acts of God, accident, or modification of, or to any part of, the product. This Warranty does not cover damage due to improper operation, maintenance or installation, or attempted repair by anyone other than Meyer-Amps. or a Meyer-Amps dealer which is authorized to do Meyer-Amps warranty work. Any unauthorized repairs will void this Warranty.
Remember, although warranty is a boring legal issue, and the reason to look in to it is never a pleasant one, we strive to help you as much as possible and make you happy again. Contact us !
Should I adjust the bias when changing power tubes
Our amplifiers featuring a class AB power output section (Brighton 20 and 45 & the Blackpool series), need to be re-biased when the power tubes are changed. Take your amplifier to an amp tech and let him/her set the correct bias as specified in the manual.
Amplifiers with cathode biased output power tubes (Brighton 14, Brighton Stereo 30) don’t have to be re-biased. Just make sure that the power tubes are matched.
How about pre-amp tubes
Pre-amp tubes may be changed without any adjustment. All pre-amp tubes within the Brighton and Blackpool series are interchangeable. Combinations of 12AX7 (ECC83 or 7025), 12AT7 (ECC81), 12AU7 (ECC82), 12AY7, 12DW7 (ECC832) and 5751 are allowed. However, keep in mind that we have done the research for you and the suggested types of the pre-amp tubes will give you the best tone and performance.
The following hints may help you when experimenting with pre-amp tubes. The 12AX7/ECC83/7025 tube is the most common used pre-amp tube. It has the highest amount of gain. The 12AT7/ECC81 is pre-amp tube with slightly lower gain compared to the 12AX7/ECC83 and is mostly used to drive effects loops or to drive the power tubes in the phase inverter, the final pre-amp tube before the signal is fed to the power tubes. 12AU7/ECC82 is a low gain pre-amp tube capable in really pushing the signal with low impedance like 6550 or KT88 power output tubes in bass amplifiers, or even a low wattage speaker. No 12AU7/ECC82 are used by us but you are free to experiment with this type of pre-amp tube.
How often should I change my tubes?
Tube life can be anywhere from 6 months to one year if played hard. Preamp tubes can last a very long time. If your amplifier starts to sound differently, i.e., less bass response or lack of power, you probably need to change your tubes. Tubes may become sensitive for mechanical distrubances like to vibrations of the sepaker a a slight touch by your fingernail. This phenomenon is called microphony and your amp has a microphonic tube. The internal structure of the tube is no longer as solid as it should be and the tube needs to be replaced.
Can I use a power attenuator?
Yes. But remember, due to the use of an attenuator you will probably push the amplifier much harder than without the attenuator. This will stress the tubes and internal electronics much more than use without an attenuator. Power tubes will degrade much faster and need to be replaced sooner than use without an attenuator. However, there is no reason why not to use an attenuator.
Are your amplifiers all tube?
All except the Brigthon Stereo 30 and upgraded Brigthon 20+ are all tube amps, including the rectifier, pre- and power-amp.
Why do you use tube rectifiers?
We believe that all components in the amplifier, including the power supply and hence the rectifier, contribute to the overall sound of the amp. Extensive testing and comparing between amps with tube rectifiers and with diode rectifiers made us decide to use rectifier tubes. Designing a proper power supply for your amplifier is much more difficult and expensive but we believe that our customers deserve the best.
How to use the stand-by switch?
First some theory about the use and abuse of stand-by switches. The power supply within tube amplifiers consist of more than one power source. An electronic tube requires a power source to heat up the internal structure by powering its filament. A low voltage, high current power source is used for this purpose. The amplification function of a tube is made possible by a high voltage power source. A tube is stressed out when the high voltage is supplied to the tube but its not heated up sufficiently. You should avoid this situation. Well, here comes the stand-by switch into play. The on-off switch powers up the amp, without putting the high voltage on the tubes, but tube heating is started. About 1 or 2 minutes the tubes are heated sufficiently and the high voltage maybe safely put to the tubes by flipping the stand-by switch to the on position.
There is one other thing that comes in to play. All Meyer Amps feature a tube rectifier. Because a rectifier tube is also a tube, and so it is heated gradually before it operates, the high voltage gradually comes up.
So, we have the following situations.
1. The amp is ‘cold’ and switched on after not operating for more than at least 10 minutes. Use the power switch to engage the amp. Wait 2 minutes and flip the stand-by switch to its on position. As an alternative, you may switch on the stand-by switch immediately after switching the power switch to on because the rectifier tube gradually puts the tubes to the high voltage. Note that this does not apply for other amplifiers solid state (diode) rectifier.
2. You used the amp for some time and you want to take a break, so you want the amp to be stand-by. Switch the amp to stand-by but leave the power switch on. When you return from you break you switch on the stand-by switch and rock.
3. When you are finished using the amplifier you put the amp down by first switching the stand-by switch to off and than putting the power down. It is important to wait a few minutes before moving the amp because the tubes are sensitive for moving when still hot.
One more thing. The naming of both positions of a stand-by switch is somewhat confusing. Although the literal meaning a standby switch in the on-position does mean that the amp is stand-by, so not operating. In practice however we consider an amplifier with its standby-switch in the on position as an engaged device. The standby switch in the off position is considered as being standby and hence not engaged. To handle this confusion we named the positions of the standby-switch on Meyer Amplifiers as standby (its standing by, so not operational) and on (engage, we may rock) , so no confusing here.
What about the impedance switch?
On the back side of your amplifier a rotary switch sets the impedance of the power output of the amplifier. This setting should match the impedance of your speaker cabinet. Most common values for impedances of amplifiers and speaker cabinets are 4, 8 and 16 Ω.
Impedance mismatch, now what?
From a technical point of view a mismatch of impedance between amplifier output and speaker cabinet causes the power amp tubes to overload. Our amplifiers are build extremely sturdy so a small mismatch (4Ω-8Ω, 8Ω-16Ω) will not damage the electronics, however we do not encourage to operate your amplifier this way.
Three situations should always be avoided:
- a large mismatch (4Ω-16Ω),
- operating the amplifier over 50% of its maximum power with an impedance mismatch and
- operating your amplifier without a speaker cabinet connected.
These situations could damage the power tubes or even worse, damage the output transformer and need replacement.
Contrary to solid state amplifiers, tube amplifiers are more resistant to a situation when the amplifier impedance is selected to a higher value than the speaker(s) impedance, i.e. amplifier impedance selector at 16Ω and a speaker impedance of 8Ω (or 8Ω and 4Ω respectively) But again, we do not encourage this situation nor we are liable for damage caused by a mismatch of impedance.
Remember: Never ever operate your amplifier without a speaker cabinet connected.
Impedance of combined speakers
When 2 or more speakers are combined the impedance of the speaker combination differs from the impedance of a single speaker. We need to do some calculations to get the impedance of the speaker combination.
Combining two speakers can be done by connecting the speakers parallel or in series. Combining more than two speakers give you more options than only in series or in parallel. Lets start with combining two speakers.
Combining two speakers
A speaker combination of two speakers my be operated mono or stereo. In a mono set-up both speakers may be put in series or parallel. When operated stereo, the speaker combination may be treated as two individual speakers or speaker cabinets.
Combining two speakers in parallel
When two speakers are combined in parallel, the + of both speakers are connected and the – of both speakers are connected. The amplifier signal is fed to the combined + of the speakers and the – of the combined speakers. Combining two speakers this way should only be done with speakers with equal individual speaker impedance and will give you an combined impedance which is half that of the single speaker impedance. The maximum power handling of the speaker combination is twice the maximum power handling of the speaker with the lowest maximum power handling.
Note that when a parallel speaker combination is overloaded most probably one of both speakers will burn out before the other. When a speaker is burned out, there is no power consumption by this speaker any more, so the other speaker must eat all the power of the amplifier and will most likely burn out also.
For two speakers wired in parallel:
Two 4 Ω speakers = 2 Ω load
Two 8 Ω speakers = 4 Ω load
Two 16 Ω speakers = 8 Ω load
Combining two speakers in series
When two speakers are combined in series, a single wire connects the + of one speaker to the – of the other speaker. Both other + and – connections are the signal wires for the speaker combination. Combining two speakers this way should only be done with speakers with equal individual speaker impedance and will give you an combined impedance which is twice that of the single speaker impedance. The maximum power handling of the speaker combination is twice the maximum power handling of the speaker with the lowest maximum power handling.
Note that when a series speaker combination is overloaded most probably one of both speakers will burn out before the other. When one speaker is burned out, the other one will survive due to the fact that the burned out speaker is an interruption of the electrical power. Note that the amplifier is not connected to a speaker or speaker combination in that case and tube amplifiers do not like that.
For two speakers wired in series:
Two 4 Ω speakers = 8 Ω load
Two 8 Ω speakers = 16 Ω load
Two 16 Ω speakers = 32 Ω load
Combining three speakers
A combination of 3 speakers is not very common however possible. Three speakers could be wired in parallel or in series. A combination of series and parallel is however possible but will only result in a useful set-up when combining speakers with different impedance and power rating.
Combining three speakers in series
Three speakers with identical impedance and power rating, wired in series will result in a combination with 3 times the individual impedance and a power rating also 3 times the power rating of the individual rating. Due to the fact that the impedances are added when wiring speakers in series, it makes only sense to wire up 3 speakers in series with 4Ω individual impedance yielding a combination of 12Ω, what is suitable for hooking up to an amplifier which is selected to 16Ω output impedance with a slight mismatch.
For three speakers wired in series:
Three 4 Ω speakers = 12 Ω load
Three 8 Ω speakers = 24 Ω load
Three 16 Ω speakers = 48 Ω load
Combining three speakers in parallel
Three speakers with identical impedance and power rating, wired in parallel will result in a combination with an impedance ⅓ of the individual impedance and a power rating and 3 times the power rating of the individual rating. Due to the fact that the impedances are divided by 3 when wiring speakers in parallel, it makes only sense to wire up 3 speakers in parallel with 16Ω individual impedance yielding a combination of 5,3Ω, what is suitable for hooking up to an amplifier which is selected to 8Ω output impedance with a slight mismatch.
For three speakers wired in parallel:
Three 4 Ω speakers = 1 ⅓ ( = 1.3 ) Ω load
Three 8 Ω speakers = 2 ⅔ ( = 2.7 ) Ω load
Three 16 Ω speakers = 5 ⅓ ( = 5.3 ) Ω load
Combining four speakers
Four speakers in a four speaker combination may be operated all in series, all in parallel or a series/parallel combination.
Four speakers may also be used in a stereo set-up where two speakers are combined to act as the left speaker combination and the other two are combined to act as the right speaker combination. The left and right speaker combinations may be combined by two speakers in series or two speakers in parallel, following the rules as given earlier.
Combining four speakers in parallel
For Four speakers wired in parallel:
Four 4 Ω speakers = 1 Ω load
Four 8 Ω speakers = 2 Ω load
Four 16 Ω speakers = 4 Ω load
Combining four speakers in series
For Four speakers wired in parallel:
Four 4 Ω speakers = 16 Ω load
Four 8 Ω speakers = 32 Ω load
Four 16 Ω speakers = 64 Ω load
Combining four speakers in parallel/series
For Four speakers wired in series/parallel:
Four 4 Ω speakers = 4 Ω load
Four 8 Ω speakers = 8 Ω load
Four 16 Ω speakers = 16 Ω load
