Decware se 84 csp owners manual

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GENERAL DESCRIPTION The SE84CSP is a line level stereo preamplifier with gain. It is an all tube design that has been point to point wired and uses no solid state parts or circuit boards. This ensures top quality sound and extreme reliability. It features a front mounted volume control that will raise or lower the output level of both channels evenly. There is no fidelity robbing balance control. Also featured are two pair of standard RCA type inputs with a front mounted toggle switch to se- lect between source A and source B. SETUP The SE84CSP is easy to set up. The tubes are not installed when it ships to pre- vent breakage. It comes with a total of 4 tubes. The largest one is called a rectifier and locates just in front of the power transformer. It fits into an octal (8 pin) tube socket. This is the only 8 pin socket on the unit so there is no worry of put- ting the rectifier tube into the wrong location. The rectifier tube shipped with the pre- amp is typically going to be a 5Y3GT. You can also substitute a 5AR4 or 5U4 type rectifier in place of the 5Y3GT. The smaller tubes (9 pin) shipped with this preamp are 6922s. They go into the white ceramic 9 pin sockets. Since all three are the same it does not matter which ones go where, but all three must be installed for the preamp to work. All of the tubes simply plug into the tube sockets with a firm downward force. It is important to check the pins on the tubes PRIOR to installing them to be sure they are not bent. Installing tubes with bent or crooked pins could damage the tube sockets. After all tubes are installed in the preamp, install the removable power cord into the rear located IEC connector, turn the volume control all the way down and turn on the preamp. The power switch is located on the rear of the preamp. Like all tube gear it will take up to 30 seconds for the tubes to warm up before the preamp will begin to work. Once the preamp is on and warmed up for a few minutes, you can connect your power amplifier to it using standard RCA type interconnect cables. The output jacks on the preamp are located on the left hand side next to the power switch. After you have connected your amplifier to the preamp and the preamp is on and warmed up, turn on your amplifier. Make sure the preamp and amplifier are plugged into the same electrical outlet so you dont develop ground loops which can cause hum. With the volume control still turned down all the way and the amplifier turned on, you should hear no hum come from the loudspeakers above the level of hum your amplifier normally has.

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Once you have confirmed that there is no additional hum from the amplifier you can connect your source components to the preamp. If you do hear additional hum from the amplifier the most likely cause is A) a bad ground in one or both of your inter- connect cables. B) a ground loop developing between the amplifier and preamp from having them plugged into different wall outlets. If either of these causes is not the case you can go on the web site www.decware.com and read the article in the articles section on troubleshooting hum problems. The SE84CSP typically has between 0.4 and 0.9 millivolts of hum and noise. This is far below the norm for tube gear and is often referred to as stone quiet. The input jacks where you will hook your two sources are located on the rear of the preamp opposite the output jacks. The toggle switch on the front top of the preamp is used to select between the two pair of jacks. You can connect any line level source to these input jacks. A line level source is typically a 2 volt source like a CD player, tuner, tape deck, vcr, phono stage and so on. You should now be able turn on your source, raise the level of the volume control slowly and start enjoying the music! NOTE: It is not recommended to have more than one source playing at the same time. For example; if you have two CD players playing CDs at the same time you may get a small amount of cross-talk or bleed-through from the selector switch. If this becomes the case, simply turn off one of the CD players, or pause it. NOTE: This preamp was designed with very low voltages on the tubes compared to most tube gear. This was done primarily for sound quality but also has the benefit of extending tube life. You can expect to get 5 to 10,000 hours out of the tubes. NOTE: Because of the lower tube voltages you can leave your preamp on 24 hours a day 365 days a year with no worries. Doing so will further increase the tube life and has the advantage of keeping the preamp fully warmed up and sounding its best at all times. NOTE: If you do decided to turn your preamp on and off with each listening session BE ABSOLUTELY CERTAIN that you turn your power amp on before turning on your preamp, and when your done, turn your power amp off before turning off your preamp. This sequence is standard for all preamps and power amps regardless of type or brand and applies to both tube and solid state models. NOTE: This preamp is factory set to UNITY gain with the volume control 1/2 way up. If you require more or less gain there is a trim control inside the unit that can be easily adjusted clockwise for more gain or counter-clockwise for less gain.