Table of Contents
Related Manuals for Phaedrus Audio PHAB
Summary of Contents for Phaedrus Audio PHAB
- Page 1 User Manual for PHAB - tube microphone preamp' PHAME - tube instrument preamp' & PHI - tube DI box This manual is also available as a pdf download, Go to: www.phaedrus-audio.com Ver. 1.1 - ©Phædrus Audio Ltd. 2011 All rights reserved.
-
Page 2: Chapter 1 - Background
Chapter 1 - Background The Phædrus Audio PHAB, PHAME and PHI products ca me about because two, recording musicians wanted to own a "classic" console from the nineteen-six ties. Ideally a famous EMI, REDD, all valve (vacuum tube) mixer used to record The Bea tles. - Page 3 Mark II console. The PHILHARMONIC a mplifier circui t is described in detail below in section Circuit descriptions Mullard published many reference designs which were used by EMI in developing the REDD amplifiers. Phædrus Audio went back to these same references to develop the PHAB, PHAME and PHI products. The prototype London Console (Mark II)
- Page 4 PHAB microphone preamp’ and PHAME instrument preamp’ PHAME The Phædrus Audio PHAME is a development of the PHAB in which the very high input i mpedance of the input pentode valve is exploi ted to provide a very high quali ty instrumental prea mplifier.
-
Page 5: Chapter 2 - Warranty And Service
Chapter 2 - Warranty and Service Please regi ster your purc hase wi th Phaedrus Audio at www.phaedrus-audio/registra tion.htm . This will simplify service & repair should you need this service. Your na me will be placed on our mailing list (unless otherwise requested) for future upda tes and new product announcements. -
Page 6: Shipping Charges
These are: PHAB-REP - Repair of a defec tive PHAB prea mp', cha rged a t a flat-ra te PHAME-REP - Repair of a defec tive PHAME prea mp', charged a t a fla t-ra te PHI-REP - Repair of a defec tive PHI DI box, charged a t a flat-ra te PHAB-MISEAJ OUR - Mise à... -
Page 7: General Safety Instructions
A 12V AC supply is required for the Phædrus Audio PHAB, PHAME and PHI uni ts. A direc t current (DC) supply is NOT sui table and will damage the uni t. If a supply is sourced el sewhere than from Phædrus Audio, it must ha ve the following specifications:... -
Page 8: Chapter 4 - About Valves (Vacuum Tubes)
US 6922. Russian 6N1P tubes and the Chinese 6N1 tube a re NOT equivalent. NEVER install a 6N1(P) in the Phædrus Audio PHAB or PHAME product. The ECC88 valve i s sill being manufac tured in China and in the... -
Page 9: Chapter 5 - Instructions For Use
Tha t said, the lifeti me of a valve (tube) is largely determined by the lifeti me of i ts ca thode emission and the small-signal valves (tubes) used in the PHAB, PHAME and PHI use oxide cathodes, which can provide adequa te ca thode emi ssion for 100,000 hours or more. Tha t's over eleven year’s continuous use. - Page 10 -quality in mind, can transform the quality of your recorded signals. Tha t is the ai m of the Phædrus Audio PHAB tube microphone prea mplifier: to offer just suc h a no compromi se microphone a mplifier in a produc t which incorpora tes the standards and qualities adopted in classic recording gea r.
- Page 11 The Phædrus Audio PHAB tube prea mplifier is built around a modular a mplifier with a fixed gain of +40dB (with a switc h available to raise this to approxi ma tely +46dB). This a mplifier is preceded by a rotary, switc hed a ttenua tor control, offering a ttenua tion of 0 to -30d B in steps of 6dB. A further pad (opera ted by a front panel switc h) is available, to increa se the a ttenua tion to -40dB;...
- Page 12 PHAME Application and connections Archi tecture of the PHAME preamp' The uni t is connec ted as shown in the accompanying diagra ms. Direc t injec tion (DI) provides a clean way of applying instruments to your mixer or computer interface.
-
Page 13: Input Attenuator
Voicing and the valve (tube) amplifier Guitar pickups are made by winding about 8000 turns of wire on a former or bobbin which surrounds several permanent magnets. The resistance of the wire is relatively low, but the inductance is high and the device therefore has a rising output impedance. - Page 14 Ground (earth) lift Hums and buzzes are the bane of an audio engineer’s life. Unfortuna tely, it is the na ture of a high- impedance, unbalanced instruments like an elec tric gui tar to be highly susceptible to the AC electromagnetic fields thrown off by all mains-powered equipment.
-
Page 15: Operating Levels
Operating levels Because of the vintage of the PHAB and PHAME prea mplifier designs and their origin in German manufac tured broadcast television and radio equipment, the envisaged opera ting level for this equipment is slightly lower than mod ern recording industry standards. - Page 16 PHI into the studio console will negate some of the benefi ts of the PHI’s unique charac ter. Use a premium-quali ty microphone prea mplifier (suc h as Phædrus Audio’s PHAB) for the very best resul ts a s shown below. Ver. 1.1 - ©Phædrus Audio Ltd. 2011 All rights reserved.
- Page 17 Controls Instrument/ Loudspeaker switch – LOUDSPEAKER MODE As a general rule, gui tar and bass gui tar and certain elec tric pianos and organs rely on the distortions in their a mplifiers and loudspeaker-cabinets for the c harac ter of their sound. Ideally of course, these instruments need to be captured with mic rophones, ra ther than applying a line- level signal to the mixer.
- Page 18 AN AMPLIFIER. NOT SO DOING WILL DAMAGE YOUR Phædrus Audio PHI. FU RTHERMORE YOU MUST OBSERVE THE WARNING GIVEN BELOW, AS FAILURE TO DO THIS COULD DAMAMGE YOUR AMPLIFIER. When the Phædrus Audio PHI is used in LOUDSPEAKER mode, it is important to observe the correct polarity of the signal fed from the amplifier to the PHI.
-
Page 19: Chapter 6 - Circuit Descriptions
Both devices opera te wi th a constant-gain a mplifier and a ttenua te the signal reaching the a mplifier for level control. In the case of the PHAB, the valve prea mplifier has a fixed gain of +40dB (with a switch a vailable to raise this to approxi ma tely +46d B). The a mplifier is preceded by a switc hed a ttenua tor control offering a ttenua tion of 0 to -30dB in steps of 6dB. - Page 20 In the case of the Phædrus Audio PHAB mic rophone prea mplifier, the grid of the input pentode i s driven from the input transformer. In the case of the PHAME, this transformer is not fi tted .
- Page 21 High Pass or Rumble filter (HPF) The input stage in the PHAB i s fed by a 1:7 transformer. When a capaci tor is included in series with the transformer pri mary (i t is usually short- circuited out of circui t), the capacitor forms a half-sec tion fil ter with the pri mary induc tance of the transformer pri mary;...
-
Page 22: Specifications
Maximum input level (INSTRUMENT): 2V RMS Maximum input level (LOUDSPEAKER): 100V RMS Gain: -18dB Power supply: 12V AC Power consumption: 2 Watts Phaedrus Audio Ltd. reserves the right to alter these specifications without notice. Ver. 1.1 - ©Phædrus Audio Ltd. 2011 All rights reserved. -
Page 23: Declaration Of Conformity
73/23/EEC Low Voltage Equipment directive The products covered by this declaration are: Phædrus Audio PHAB – microphone preamplifier; Phædrus Audio PHAME – instrument preamplifier; Phædrus Audio PHI – DI-Box. The basis on which conformity is being declared: The manufac turer hereby declares tha t the produc ts identified above comply with the protec tion... - Page 24 Appendix - TEST PRO-FORMA Product: PHAB / PHAME Serial Number: ________________ Tested by: ________________ V1 vol ts: ___________ Vol ts TP1: ___________ Vol ts TP2: ___________ Gain set: ______dB (40dB or LOW GAIN posi tion) High ain test Pass / Fail...
Need help?
Do you have a question about the PHAB and is the answer not in the manual?
Questions and answers