Frequently Asked Questions
EQP-WA
Most tube manufacturers rate their tubes for 10,000 hours of continuous use. The EQP-WA requires one (1) 12AX7 and one (1) 12AU7. For stereo use, there can be some benefit from ordering some tubes in gain-matched pairs.
Some of the tell-tale audible signs of a tube wearing down are: loss of signal, low signal, loss of detail or high frequency response, severe microphonics (resonating in response to physical vibration) and excessive hum or noise. None of these things should come into play until many years after initial purchase."
Yes, very often the EQP-WA will exhibit a slight 'gain bump' of usually just a couple db, very much just as the classic units did as well. The reasons for this have to do with how the original classic units were designed. They were made to drive a 600 ohm load, in an era where all equipment was made for 600 ohm to 600 ohm coupling. This may cause the EQ to appear to have a hotter output when connected to most modern pieces of equipment, such as interfaces or converters, that have a more sensitive 10k ohm or higher line input impedance.
If the EQP-WA were connected to a vintage console or tape machine, it may appear to have unity gain when set to zero. Ideally, the EQP-WA will be connected to equipment that has some sort of trim adjust on the line input, and can be adjusted back to unity; but in the event that this is not the case, simply dial down the input level feeding into the EQP-WA. Later editions of the EQP-WA incorporate a 'tube gain adjust' calibration feature on the rear of the chassis, which allows for a gain calibration range of about +/-3db. This is useful for calibrating two units to each other, or to unity, for stereo bus use; however earlier models of the EQP-WA are still perfectly good for these applications.
There is no modification that can link a pair of EQP-WA's. Newer production EQP-WA units do have a tube gain adjust feature built in, which can be used to match the output level of a pair of EQP-WA's.
This modification is done to older EQP-WA models for a modest fee by one of Warm Audio's US dealers, Zen Pro Audio, and by one of Warm Audio's European distributors, NOVA Music.
• Zen Pro Audio
• Nova Music
We do not recommend this. The EQP-WA technically has one transformer coupled input and output, wired in parallel to an XLR and a 1/4 TRS connection merely for convenience.
Two inputs at the same time should never be connected. The EQP-WA may be able to drive two outputs well, depending on the impedance characteristics of the two devices; but as a general rule we advise against this.
TB12 Tone Beast
The cleanest setting will always be achieved by having a relatively low gain with a relatively high output (master); conversely, the most over-driven sound will always be achieved by having a relatively high gain with a relatively low output (master). With regards to specific settings, the X18 op-amp is a much cleaner and more modern discrete op-amp than the X731.
The modern (electrolytic) capacitors are cleaner than the vintage (tantalum) capacitors in most applications. The high-nickel output transformer is cleaner than the steel-core output transformer, which will produce more low frequency harmonic distortion when over-driven. Bypassing the output transformer alltogether in favor of an electronically balanced output is cleaner still, as even the nickel core transformer adds a slight sheen or polish, by design, to the sound.
The Tonebeast becomes exactly like the WA12 when set to Vintage capacitors, Steel-core output transformer, and X731 discrete op-amp, with the output level (master) turned all of the way up.
Engaging the TONE button lowers the input impedance of the input transformer, and moves the input transformer to higher turns ratio (1:8 opposed to 1:4 without TONE engaged). This gives the mic preamp a hotter signal, and also adds a bit more thickness and coloration. Having the TONE button engaged is also more in line with how the classic monolithic '12-style preamps behaved; however, we have found that a more open and natural sound, with greater headroom, can be achieved by not engaging the TONE button. As with anything, let your ears be the final judge on when to use this feature.
Yes, the TB12 Tonebeast can accept any op-amp that is designed to work on +/-16v rails and conforms to the API 2520 socket standard.
We ship the Tonebeast with our reproduction of the (Melcor) 1731 and (Jensen) 918, which are a good contrast that give you a bit of vintage and grit (x731) or modern detail and clarity (x18).
No. The XLR inputs are mirrored on the front and back for convenience only. Only one microphone and microphone cable should be attached at any given time.
Use an unbalanced 1/4 TS cable to go out from the TB12 into an unbalanced line input.
We do not recommend this. The TB12 technically has one transformer coupled output, wired in parallel to an XLR and a 1/4 TRS connection merely for convenience. The TB12 may be able to drive two outputs well, depending on the impedance characteristics of the two devices; but as a general rule we advise against this.
For the very cleanest and best results, yes. In some rare cases, the microphone cable can act as an antennae for EMI/RFI if it remains connected to the device while using the instrument input. This is not always the case; but it has been known to happen.
TB12 500 Tone Beast
Yes
The cleanest setting will always be achieved by having a relatively low gain with a relatively high output (master); conversely, the most over-driven sound will always be achieved by having a relatively high gain with a relatively low output (master). With regards to specific settings, the X18 op-amp is a much cleaner and more modern discrete op-amp than the X731.
The modern (electrolytic) capacitors are cleaner than the vintage (tantalum) capacitors in most applications. The high-nickel output transformer is cleaner than the steel-core output transformer, which will produce more low frequency harmonic distortion when over-driven. Bypassing the output transformer alltogether in favor of an electronically balanced output is cleaner still, as even the nickel core transformer adds a slight sheen or polish, by design, to the sound.
The Tonebeast becomes exactly like the WA12 when set to Vintage capacitors, Steel-core output transformer, and X731 discrete op-amp, with the output level (master) turned all of the way up.
Engaging the TONE button lowers the input impedance of the input transformer, and moves the input transformer to higher turns ratio (1:8 opposed to 1:4 without TONE engaged). This gives the mic preamp a hotter signal, and also adds a bit more thickness and coloration.
Having the TONE button engaged is also more in line with how the classic monolithic '12-style preamps behaved; however, we have found that a more open and natural sound, with greater headroom, can be achieved by not engaging the TONE button. As with anything, let your ears be the final judge on when to use this feature.
Yes, the TB12 Tonebeast can accept any op-amp that is designed to work on +/-16v rails and conforms to the API 2520 socket standard.
We ship the Tonebeast with our reproduction of the (Melcor) 1731 and (Jensen) 918, which are a good contrast that give you a bit of vintage and grit (x731) or modern detail and clarity (x18).
For the very cleanest and best results, yes. In some rare cases, the microphone cable can act as an antennae for EMI/RFI if it remains connected to the device while using the instrument input. This is not always the case; but it has been known to happen.