Ace Amp Specifications & Price
PRODUCT SPECIFICATIONS
Amplifier Output Impedance = 1.33 ohms into an 8 ohm speaker
Damping Factor: (With -8 dB of negative feedback)
5.4 -- for 4 ohm speaker load
6.0 -- for 8 ohm speaker load
6.6 -- for 16 ohm speaker load
Higher Damping Factor minimizes a change in loudspeaker's SPL as the speaker's load impedance changes. The Ace's power output changes 0.6 dB for every doubling of the speaker impedance.
Distortion: Total Harmonic Distortion is below 1.0% at 5 Watts
Power Output: The Ace Amplifier produces 8 Watts of usable(acceptable distortion) power output.
Frequency Response: Measured into Reactive Load (8 ohm resistor with paralleled 2 uF capacitor)
20 Hz to 20 kHz +/- 0 dB at 1 Watt Reference Output
Frequency Response in Octaves is 11 Octaves -- 16 Hz to 33 kHz +/- 1 dB at 1 Watt of power
No change in Frequency Response with 4, 8 or 16 ohm loads
Sensitivity: 400 mv rms for 1 Watt of power -- 1.40 V rms for 8.0 Watt of power
Signal to Noise Ratio: Below 90 dB unweighted
Chassis and Cover construction: One piece 0.063"--1.6mm thick aluminum deep drawn enclosures with large radius corners. The radius corners reduce mechanical resonance, improve the amp’s appearance and facilitate easy handling. Aluminum was chosen over steel due to the improved sound performance of non-ferrous audio chassis and aluminum’s superior corrosion resistance.
Chassis Bottom Plate: The chassis bottom plate is made of 0.125”—3.2mm thick aluminum. The bottom plate’s width and length is smaller than the chassis to provide a 0.375" or 9.5mm wide ventilation slot around the bottom perimeter of the amp. The slot provides convection cooling to the interior of the chassis. The thick bottom plate help dampen mechanical resonance.
Chassis Feet: Four 1.000"--25mm wide by 0.375"—9.5mm high neoprene rubber feet elevate the chassis to facilitate ventilation and damp the chassis from external vibration.
Chassis Finish: A cordovan powder coat finish is applied to the inside and outside surfaces of the cover, chassis and bottom plate. This attractive, durable and non-conductive finish also dampens mechanical resonance. A clear coat finish is applied for a high gloss and durability.
Class of operation: -- A1
Circuit Description: The Ace amp uses tubes. The Ace amplifier circuit uses a triode voltage stage and a pentode output stage. The output tube is operated in an "ultralinear" configuration. A pentode and a triode tube have very dissimilar distortion characteristics. Properly executed, a tube amplifier design can use the different distortion characteristics of the two tube types to cancel the overall distortion artifacts of the amplifier. This method is found in the Western Electric 91A Valve Amplifier, and to our knowledge the first successful application of this idea.
Tube Bias: Both tube stages use cathode resistors for “self” or cathode bias operation. Large value cathode bypass capacitors are used to reduce distortion, increase gain and extend bandwidth. The voltage amplifier stage is capacitor coupled to the output amplifier stage.
Fuse Type: 0.5 Amp Slow Blow 250 VAC 5 mm X 20 mm
Variable Feedback Selector: The Ace amplifier uses a rotary switch to select the optimum amount of negative feedback. See the ACE Product Manual’s Operating Recommendations for more information:
Position 1 -- Infinite or zero negative feedback
Position 2 -- minus 1 dB negative feedback
Position 3 -- minus 2 dB negative feedback
Position 4 -- minus 4 dB negative feedback
Position 5 -- minus 6 dB negative feedback
Position 6 -- minus 8 dB negative feedback
The use of variable feedback allows the user to select the proper feedback setting to compensate for the valves used and the loudspeakers selected.
Internal Construction: Single Terminal Board with hard wired and point to point soldered construction.
Input Connector Type: RCA female phono chassis jack
Input Impedance: 950 kOhms (Single ended), 250 kOhms with optional volume control
Line or Mains Voltage Requirements: USA -- 120 VAC 60 Hz -- Export versions available for any standard line or mains voltage and frequency
Output Connector Type: Standard 5-way binding posts (Red for Positive, Black for Common)
Output Impedance Loads: 4 to 16 ohms (no terminal rewiring required)
Standard Power Cord: A 6' or 1.83 meter 3 conductor power cord with an IEC 320 female chassis plug and the appropriate (based on respective country's requirements) male three prong plug.
Power Entry Module: A multi-function module located on the rear face of the chassis consists of an IEC 320 male power inlet, fuse holder (with spare fuse) and power switch.
Power Supply: The Ace Amplifier's power supply uses an isolation type power transformer with a ground screen. This completely isolates the amplifier’s power supply from noise present in the AC power lines. Soft-recovery rectifier diodes reduce voltage spikes in the high voltage supplies.
The power supply includes a RC soft-start circuit that slowly ramps up the high voltage plate supplies. This feature greatly increases tube life.
Transformers: The power and output transformers use EI cores. The output transformer is gapped to provide wide bandwidth performance with DC current present in the primary winding.
Transformer Mounting: Both the power and output transformers are bracket mounted in OEM low durometer rubber grommets to reduce mechanical noise and improve sound performance.
Tube Compliment: 1 each 12AX7 type voltage amplifier, 1 each 6L6GC type power amplifier
Tube Substitution: The Ace amplifier can use a variety of tube types.
Voltage Amplifier -- 12AX7, 12AY7, 5751, 6072A, 7025A, ECC83
Power Amplifier -- 6CA7, 6L6 (all types), 1614, 1622, 5881, 5932, 7027A, EL-34, KT-66 & KT77
Parts Selected: The specific parts used in these amplifiers were selected through rigorous testing and extensive listening evaluations. Abacus tested a wide variety of "audiophile grade" parts. We do not recommend any substitutions, except for tube types (See ACE Product Manual’s Operating Recommendations). The power and voltage ratings of the parts were selected to ensure excellent long-term reliability.
Capacitors: Bypass Capacitors = Nichicon best grade Audio Muse electrolytic capacitors
Power supply Capacitors = LCR Electrolytic and OEM tin foil polypropylene film bypass
Signal Coupling Capacitors = OEM tin foil and polypropylene film capacitors
Diodes (Isolation): Motorola Axial Lead Shottky Rectifier Diodes
Diodes (Rectifier): General Instruments Soft-Recovery Diodes
Hardware: Black Oxide Coated Stainless Steel
Input Connector: Vampire PM1F RCA Female Chassis Jack
Resistors: Low Voltage Low Current = Roederstein metal film
High Voltage Low Current = 2 Watt RCD 5% carbon Film
High Current = OEM copper lead and copper end cap wire wound
Solder: Chimera Laboratories "Classic Copper" solder
Speaker Binding Posts: Vampire BP-3 5 way binding posts
Terminal Boards: Tinned Brass yoke type terminals to improve conductivity
Transformer Laminations: "Orthosil" EI laminations as developed by Western Electric
Tube Types: Sovtek 12AX7LPF and Svetlana 6L6GC-SVT
Valve Sockets: White ceramic or steatite sockets with gold plated contacts
Wire: Chimera Laboratories 20.5 and 25.5 AWG Continuous Cast Copper solid core wire with sprayed on double coat of 0.0005" thick insulation. This wire is used in single strand, spiral twisted and Litz braided configurations.
Warrantee: Five years parts and labor -- This includes tubes
Weights and Dimensions:
Ace Amplifier dimensions -- 9" - 229 mm wide, 6.5" - 165 mm high, 7.5" - 191 mm deep
Ace Amplifier Weight -- 10 lbs. - 4.54 kg each
Packaging per Pair -- 22" - 56 cm X 14" - 36 cm X 12" - 30.5 cm high, 26 lbs. - 11.8 kg
Packaging per unit -- 14" - 36 cm X 14" - 36 cm X 12" - 30.5 cm, 15 lbs. - 6.8 kg
Price: Introductory Price -- $ 1145 USD per pair, $ 580 USD per unit, price does not include shipping
Retail Price -- $ 1390 USD per pair, $ 700 USD per unit, price does not include shipping
ACE AMPLIFIER OPTIONS
A. OFC Connectors: Install oxygen free copper connectors in the amplifier.
RCA Chassis Jack -- Vampire PM1F/OFC - OFC metal base with Hard Gold finish
Speaker Binding Posts -- Vampire BP-HEX/OFC - OFC metal base with Hard Gold finish
Replacing the standard brass body connectors with OFC provides a significant improvement in transient performance and low level detail resolution. The lack of nickel or silver sub-plating reduces any glare or grain in the upper midrange and high frequency.
Price: $ 93.00 USD per pair, $ 46.50 per unit
B. Input Volume Controls: ALPS 40mm Black Beauty potentiometers - Installing a monophonic volume control in the Ace amplifier offers two advantages; one, you do not require a line preamplifier stage. Two, you realize the full sonic benefits of a passive potentiometer stage in the right place, at the output end of the interconnect. At first glance, the option price of install this option may seem to add a significant cost to the amplifier's price. But when you compare these prices to the additional cost of a quality tube preamplifier, it's a bargain. Please remember these options do not include installing multiple input jacks and a source selector switch in the amplifier. There is not enough room in the ACE Amplifier for a properly implemented switch.
The volume controls are installed in the front fact of the amplifiers mounted in a hole usually covered by the Abacus Audio Logo. We supply a special large Aluminum knob with our Logo installed in its face.
Price: $ 99.00 USD per pair, $ 50.00 per unit
C. CCC Power Cord: Replace Standard Cord with 14 AWG Continuos Cast Copper Power Cord.
High quality hospital grade IEC 320 and male line or mains plugs are used. CCC wires are soldered to plugs with Chimera Laboratories copper content solder. A tough black polyester braided sleeve is used to protect the wires. The power cord is unshielded. The cord's diameter is approximately 0.5" -- 13 mm. Cable Length is 6' -- 1.83 meters. Custom lengths are available
This power cord offers a significant performance improvement over standard power cords.
Price: $99.00 USD per pair, $ 50.00 per unit
Ace 8 Watt Single Ended Tube Amp