Phono Preamp FAQ!

What's a phono preamp and do I need one?

If you've ever listened to a vinyl record, you've most certainly listened to it through some type of phonograph preamplifier! A phono preamp greatly amplifies the tiny signals emanating from your phono cartridge so they’re at the same approximate level as other sources such as CD player or DAC. It also implements a specific equalization curve developed by the Recording Industry Association of America (RIAA) so that all records play correctly with universal compatibility on all turntables. If you take an ordinary turntable and try to plug it directly into a line or auxiliary input or sound card with no preamp, you'll barely hear anything but a faint, scratchy whisper. Note that 78-rpm records used a different equalization standard (actually, several different standards) and for best results should be played only with a specialized cartridge and preamp.

Don't most receivers have built-in phono preamps?

It depends; older models, yes. Newer A/V receivers sometimes don't and require an external phono preamp, which you then connect to an auxiliary line input. Even if your receiver has a built-in phono preamp, an external preamp might offer a significant improvement in sound. Just be sure to connect the output of the preamp to an aux or tape input, not the jacks labelled phono.

Why vacuum tubes?

Many listeners simply prefer their sound. Low-level stages such as phono and microphone preamplifiers seem to especially benefit from the uniquely clear, open, three-dimensional sound of a great tube-based design.

How long do tubes last, and how often should I replace them?

Simply put, tubes should be replaced when the noise level becomes objectionable or the sound quality is audibly degraded from new.  Tube life can be unpredictable, especially with new-production tubes, but a couple thousand hours is not uncommon, similar to that of a typical phono stylus.  Leaving the unit on for very long periods of time or cycling the unit on and off excessively can adversely affect tube life.

What tubes should I use in my preamp?

All my preamps ship with new JJ E88CC tubes selected for low noise, low microphonics, and balanced triode sections.  This is a good choice for replacement.  Some users report good results with NOS (new-old-stock) USA and European types; just be advised that tubes purchased through vintage tube vendors might not be screened for noise, microphonics, and balance.

Who should replace the tubes in my preamp?

If you’ve never replaced tubes in audio or guitar equipment before, please refer the unit to an experienced local technician.  Tube amplifiers contain hazardous voltages and high temperatures and are not designed to be user-serviceable.  Alternatively, you are welcome to send the unit to me for tube replacement and evaluation; user only pays shipping and tube costs, no additional charge for installation and performance testing.

What is covered under warranty?

If your preamp fails within the five-year transferable warranty period due to non-tube-related manufacturing or component defects, simply ship it to me and I will repair, evaluate, and send your preamp back to you at no cost.  Please note that tubes are not covered under this warranty.  Moreover, this warranty is void if the unit has been upgraded or modified in any way. 

What about service outside the warranty period?

If your unit is performing differently than expected outside the warranty period and you’ve ruled out tube replacement as the remedy, I strongly encourage you to contact me first. I can probably service your preamp to new condition faster and cheaper than anyone on the planet. I know these units literally inside and out.

How much preamplifier gain do I need for my system? Is 34 dB enough?

The required phono gain of any audio system depends on many factors, chiefly among them the output level of your cartridge and the sensitivity of your receiver or line stage and power amplifiers. For most moving-magnet (MM) and high-output moving coil (HOMC) cartridges with outputs greater than 2 mV, either of my preamps will work fine; but this also depends on line stage and power amp gain and how important it is to have identical volume control settings between sources such as phono and DAC. Personally, I like the Ortofon 2M Black cartridge with its high 5 mV output and this will drive my Model 1000 Mk. II (34 dB) or Model 2200 (40 dB) perfectly with only minor volume adjustments between sources. For lower outputs, such as the Sumiko Blue Point No. 3 high output moving coil cartridge at 2.5 mV output, the Model 2200 might suit many listeners’ systems better but the Model 1000 Mk. II would still work fine provided turning up the volume a little bit when switching to phono is acceptable. For low-output carts like the Ortofon MC Quintet Black S at 0.3 mV, an external pre-preamp or stepup transformer such as the Ortofon ST-7 is mandatory, as this results in equivalent preamplifier gains of 58 and 64 dB for the Model 1000 Mk. II and Model 2200, respectively.

Besides gain, would either of your preamplifiers be advantageous over the other for a given system?

Either preamplifier will drive any line input satisfactorily, but the Model 2200 has better output drive capability into loads as low as 5 kΩ owing to its use of Alan Kimmel’s amazing Hybrid Mu Stage gain blocks. Check the input impedance of your receiver, line stage, sound card, or ADC. The Model 1000 Mk. II will drive any load greater than 10 kΩ but is happiest above 25k.

I have one of those USB turntables that I connect straight to my computer. Do I need a phono preamp?

USB-type turntables have preamps and analog-to-digital converters built into them so you can just plug and play into a laptop or desktop computer, but they may also have direct outputs from the cartridge, from which you will likely get better results with a high-quality outboard phono preamp.