LOWPASS ON/OFF Pushing this button IN engages the Lowpass filter. Pushing this button OUT will bypass the filter. LOWPASS FREQUENCY Turning this control sets the Lowpass crossover point from 50Hz (fully counterclockwise) to 5kHz (fully clockwise). HIGHPASS FREQUENCY Turning this control sets the Highpass crossover point from 50Hz (fully counterclockwise) to 5kHz (fully clockwise). HIGHPASS ON/OFF Pushing this button IN engages the Highpass filter. Pushing this button OUT will bypass the filter. X-OVER OUT This crossover is fully independent. Signal can be parallel routed from the CH 1/2 INPUTS (X-OVER INPUT SELECT button set to the IN position) or be directly sent to this crossover via the AUX. X-OVER INPUT RCA jacks (X-OVER INPUT SELECT button set to the OUT position). This configuration allows the AUX. crossover to be used with a separate amplifier not equipped with its own on-board crossover for the ultimate in system flexibility. Note: By engaging both Highpass and Lowpass filters and setting the desired crossover points, a Bandpass filter can be created:
D7 CROSSOVER FREQUENCIES Diamond Audio D7 Professional Reference Series Amplifiers feature fully variable crossovers. The frequency control knobs (located in the tray on the top of the amplifier) are labeled 50Hz when the knob is rotated fully counterclockwise (left) and 5kHz when rotated fully clockwise (right). To make basic setting of the crossover frequencies a little easier, weve come up with the following rotational diagram: HIGHPASS/LOWPASS FREQUENCY
Notice that the outer most circle of numbers (1:00, 2:00, etc.) represent numbers as they appear on the face of a clock. The number underneath each hour designation on the simulated clock face is the approximate crossover frequency at that position. BRIDGING All pairs of Diamond Audio D7 amplifier channels are capable of being bridged to a 4 Ohm mono output. Creation of the mono channel is accomplished by using the left channel positive (+) output connection of the amplifier for the speaker positive and the right channel negative (-) output connection of the amplifier for the speaker negative.
AUXILIARY CROSSOVER Signal can be routed from the channel 1/2 INPUTS (X-OVER INPUT SELECT button set to the IN position) or combined with the CH 3/4 INPUTS (X-OVER INPUT SELECT button set to the OUT position). These signals can then be processed by the third (AUXILIARY) crossover. This additional independent crossover can be used with a separate amplifier not equipped with its own on-board crossover for the ultimate in system flexibility.
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Note: It is important that a 4 Ohm minimum total speaker impedance load is observed! If an impedance load of less than 4 Ohms is used, you will eventually damage your amplifier and void your warranty. RCA INPUTS AND OUTPUTS
Note: To set crossovers, first remove the two 1/16 Allen screws holding down the security cover using the Allen key provided. When reinstalling the cover be careful not to overtighten the screws. Damage to the cover may result.
As seen in the above drawing, the function of the RCA inputs, outputs, and feature buttons are as follows: CH 1/2 INPUT The RCA cables from your source unit should be inserted here. -12dB BUTTON: CH 1/2 To the right of the CH 1/2 INPUT RCAs you will find the -12dB button. Pushing this button: IN allows your amplifier to accept signal voltages as high as 12VRMS. Pushing this button OUT configures the amplifier to accept signal voltages up to 6VRMS. AUX. X-OVER INPUT These RCA jacks allow you independent access to the AUX. X-OVER. X-OVER INPUT SELECT Pushing this button IN routes signals from the CH 1/2 INPUTS to the inputs of the AUX. X-OVER. Pushing this button OUT allows independent access to the AUX. X-OVER. AUX. X-OVER OUT These RCA outputs are used to provide filtered or unfiltered signals to an outboard processor or amplifier. By pushing the X-OVER INPUT SELECT button to the IN position, and pushing the LOWPASS ON/OFF and HIGHPASS ON/OFF crossover buttons to the OUT position, signals available at the CH 1/2 INPUTS will bypass the crossover and be made available at the AUX. X-OVER OUTPUT RCAs allowing you to daisy-chain multiple D7 amplifiers for the ultimate in system design flexibility (see block diagram page 16).

CROSSOVER CONTROLS: CH 1/2 As seen in the above drawing, the function of the crossover controls (from left to right) are as follows: GAIN This control matches the output voltage of the source unit or processor to the amplifier inputs. Rotating this control to the MIN mark (counterclockwise) configures your D7 amplifier to accept input voltages as high as 12V RMS with the -12dB button pushed IN (see RCA INPUT drawing on page 12). This control should be set as low as possible. The basic procedure for setting input gains is as follows: 1. Adjust all amplifier gain controls to just above the minimum setting (fully counterclockwise). If your source unit output voltage is less than 6 Volts RMS, push the 12dB button for the selected channel pair to the OUT position. If the available signal voltage is more than 6 Volts RMS, push the -12dB button to the IN position. Using the highest quality source (usually CD) play some music and slowly turn up the source unit until you can hear distortion. Now turn down the volume until the distortion stops. This is your maximum source unit level. Turn up the amplifier gain until audible distortion starts. Turn down the gain to the point JUST BELOW the start of the distortion. Repeat step 3 for all amplifiers in your system.
Please refer to the Diamond Audio Level Setting Technical Brief available from the Tech Department for a comprehensive level setting procedure.
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SPEAKER WIRING Diamond Audio recommends using speaker wire of at least 16 gauge. Lay out the wire in the vehicle from the individual speaker locations to the amplifier(s). Observe safe wiring precautions. Your D7 Professional Reference Series Amplifier will accept speaker wire up to 10 gauge directly. Locate the speaker terminal block on the end of the amplifier. Strip approximately 1/2 inch of insulation from the wire, insert the wire into the terminal, and tighten the Allen screw. Repeat for all speaker wires. Please observe our recommended minimum speaker impedances to prevent possible damage. Banana Jacks using up to 8 gauge wire can be inserted into the speaker block. Remove the set screw completely and insert the Banana Jack into the end of the block.
THERMAL MANAGEMENT SYSTEM All D7 Professional Reference Series Amplifiers feature our Intelligent Thermal Management System. All amplifiers feature one or two (depending on model) internally mounted temperature-controlled cooling fans. Care should be taken to allow adequate breathing room (approximately 2 inches) on all sides of the installed amplifier to allow the system to operate at peak efficiency. Cool outside air is drawn into the amplifier through the side vents on each end panel. The air is then drawn over the top of the main circuit board, down through the fan over the internal heat sink fins (in two directions) and out through exhaust vents on the bottom of each end panel. In this way, the cooling fan(s) remain nearly inaudible under almost all listening conditions.

CROSSOVERS All Diamond Audio D7 amplifiers employ the most flexible internal crossover sections currently available in mobile audio. They feature third-order 18dB/ octave Butterworth filters. These filter networks sum to a flat response at their -3dB break points. This results in a smooth and seamless transition from one frequency band to the next. Butterworth filters provide maximally flat frequency responses when compared to other filter structures. All crossover controls are mounted on the top of the amplifier. Each crossover is continuously variable from 50Hz to 5kHz. Each pair of channels has an individual network that can be configured to Highpass, Lowpass, Bandpass or All-pass by simple switch selection. When switched off, they are completely out of the audio path. Two and four-channel D7 amplifiers also provide a separate fullyindependent crossover for the output RCA jacks providing filter control of any other amplifier.
When D7 amplifiers operate at high power for prolonged periods, the temperature sensors instruct an intelligent monitoring circuit to speed up the fan(s) until the amplifier has cooled down to its normal operating temperature. Amplifier models D7402 and D7104 also feature our unique Power-Flow Busbar. The shroud connecting and covering the two internal cooling fans of these amplifiers is made of solid nickel-plated copper. Each end of this fan shroud is soldered to full width pads on the main circuit board. The center of this shroud is attached to the fans at eight points. The high current ground path for the speakers now travels over the cooling fans through the shroud, which functions as a busbar. At the same time, these high current signals are completely isolated from the circuit board traces that carry low-level signals.
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An additional temperature monitoring circuit protects the D7 amplifier under extreme high power or extreme high-ambient temperature conditions. As the heat sink temperature reaches 185 degrees Fahrenheit, this circuit gradually turns down the high-current rail voltages, reducing the amplifier power dissipation. This circuit only effects the high current stage of the power supply; the operation of the sensitive low current audio circuits remain unchanged. Only the maximum output power is affected, and only until the heat sink cools down. Under no conditions will the D7 Series amplifiers have to shut off completely. If a problem arises, refer to the troubleshooting section (page 15) or call the Diamond Audio Technical Department at (480) 813-6205 for assistance. A WORD ABOUT BATTERIES AND HIGH OUTPUT ALTERNATORS The battery in your car is a chemical storage device for electrical energy generated by the alternator. It is capable of briefly supplying high currents for cold starting the vehicle as well as powering other important electrical loads either partially or entirely for a limited period when the engine is off. In order to supply the power required for ignition, lighting, large audio systems etc. a car needs its own efficient, reliable, and constantly available source of energy. When the engine is stopped, the battery is the vehicles energy source. When the engine is running, the alternator is the on-board electricity generating plant. It is the job of the alternator to supply power to all current-consuming loads (including the audio system). Alternator output, battery capacity, and power demand of all electrical loads and systems must be matched as ideally as possible so the entire system is reliable and trouble-free in operation. In the most basic of terms, this means that car audio is gasoline powered. Extra batteries are primarily for the extended operation of your audio system when the engine is off or for SPL competitions where high sound pressure levels are generated for short periods of time and large battery racks are needed to provide the necessary current demanded by the many amps used. D7 Professional Reference Series Amplifiers are capable of reproducing concert level volumes with incredible accuracy. Care must be taken to ensure that your vehicle is capable of supplying the voltage and current required by such a system.

POWER CABLE GAUGE CHART

Note: If you are installing multiple amplifiers, add up the total current draw for all of them and choose the appropriate gauge based on the grand total. Example: Amplifier 1: D7054 (driven at 4 ohms) = 33 amps Amplifier 2: D7152 (driven at 4 ohms) = 50 amps Amplifier 3: D7152 (driven at 4 ohms Bridged) = 100 amps Grand Total = 183 amps
D7152 and D7402 manual #135.p8/30/2002, 2:28 PM
TURN-ON CONNECTION (REMOTE) Locate the terminal labeled REMOTE between the ground and +12V power connection points on the end of the amplifier. Your source unit should have a wire in its harness labeled REMOTE or AMP TURN-ON. Some source units come equipped with a Power Antenna lead only. This should also work. Run this wire from your source unit to the amplifiers REMOTE connection. Strip approximately 1/2 inch of insulation from the wire. Insert the wire into the terminal, and tighten the Allen screw. Your D7 Professional Reference Series Amplifier will accept remote turn-on wire up to 10 gauge directly. AW ORD ABOUT POWER AND GROUND CABLE GAUGE The following basic formula can be used as a quick guide to determine the total amperage draw of a mobile audio system. This formula is based on a 50% amplifier efficiency rating. Diamond Audio D7 amplifiers are more efficient. Others may be less. Using cable of a larger gauge will only increase the current capability of your system. Do not use cable of a smaller gauge than suggested here. FORMULA: Total amplifier rated RMS power x 2 = Total Input Wattage Total Input Wattage = Current Draw (in Amps) Battery Voltage EXAMPLE: An D7152 amplifier has 2 channels at 150 Watts per channel RMS into 4 Ohms totaling 300 Watts. Work the formula as follows: 300 Watts x 2 = 600W 600W = 50A Total Current Draw 12V If the same amplifier is being driven to a 2 Ohm stereo or a 4 Ohm mono load, double the total wattage number: (D7152 = 600W @ 4 Ohms Mono) x 2 = 1200W 1200W = 100A Total Current Draw 12V
If you are considering a high output alternator or if you are not sure if your vehicles charging system needs to be upgraded, consult your Authorized Diamond Audio Dealer. They will be happy to set you up with everything necessary for you to enjoy a listening experience in your vehicle without equal. BASIC TROUBLESHOOTING 1. Amplifier has no output. Is LED (located on power/ground endpanel) lit? Yes: Make sure audio signal is present at RCA inputs. If no signal is present, use alternate signal source and try again. If signal is present, check configuration of crossovers. If still no signal, contact your authorized dealer. No: Check power, ground and remote wire for +12V. Verify all connections. If voltages are correct and still no LED, contact your authorized dealer. Note: The following steps apply to each pair of channels on your amplifier. 2. Sound in one channel only. Reverse left and right RCA cables at amplifier inputs. Is the sound now in the opposite channel? Yes: Reverse the input RCA cables in every product installed BEFORE your amplifier until the problem is found. Check RCA cables for open connections. Repair as necessary. No: Check the speaker or speaker wires of the dead channel and repair as needed. If speaker and wire are OK, contact your authorized dealer. 3. One or more pairs of amplifier channels squeal when operating. One or more speaker wires are shorted or one or more speaker voice coils are shorted or rubbing. If speakers and wires are OK, contact your authorized dealer. 4. Amplifier volume gets gradually softer as music is playing without touching any system controls. Amplifier is going into thermal protection. Make sure amplifier has room for fan(s) to breathe. Preventing air from reaching the heatsink will cause the amplifier to overheat, as will running the amplifier at too low of an impedance.

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AMPLIFIER BLOCK DIAGRAM (D7152 AND D7402)
to the bare metal using a bolt, star washer and nut. Seal the area from above and below to prevent rust. Strip approximately 1/2 inch of insulation from the other end of the cable and insert it into the ground block on the amplifier and tighten the Allen screw. ENDPLATE DIAGRAM (POWER/GROUND REMOTE)
For multiple amplifier systems, a ground distribution block is recommended. Cut a length of cable long enough to go from the ground distribution block to the amplifier. Strip approximately 1/2 inch of insulation from each end of the ground cable. Insert one end into the ground distribution block and tighten the Allen screw. Insert the other end of the cable into the ground block on the amplifier and tighten the screw (A ring terminal may be used here). Repeat for each amplifier installed. Run a cable (the same gauge as the main power cable) from the ground distribution block to the negative terminal of the system battery. Your D7 Professional Reference Series Amplifier is designed to accept up to 4 gauge power and ground cable when using the Direct (stripped wire end) Connection method. When using ring terminals to attach the power and ground, cables of up to 1/0 gauge can be used. Please refer to the Power Cable Gauge Chart (page 7) for the minimum recommended wire gauge.
D7152 and D7402 manual #135.p8/30/2002, 2:32 PM
warranty. Mounting your amplifier inside an enclosure is not a good idea unless the enclosure is equipped with ventilation fans to circulate fresh air through the enclosure. Your new D7 amplifier features adjustable mounting flanges. Should they need to be moved to a different location, remove the self-tapping screws on the bottom of each mounting flange. Move the flange to the desired location. Carefully tighten the self-tapping bottom screws. Be careful not to overtighten these screws or damage to the head of the screws or stripping of the threads will result. POWER/GROUND D7 amplifiers need proper power and ground connections to deliver maximum performance and efficiency. This is typically the least understood part of the installation process. Voltage drops due to poor quality connections and/or poor grounding practices will rob your audio system of power that could be used for listening to music. These voltage drops will create increased current draw and will make it easier for noise to enter your system. Your new amplifier has a fully regulated power supply. It is designed to make full power even if the voltage changes. It will draw more current at lower voltages to make that power. Try to ground your system to a single point in the vehicle. The gauge of the power and ground cables must be capable of handling the current needed by the entire system. Power and ground cables must be of the same gauge. If the alternator is not capable of supplying enough power for both the vehicle AND the audio system, a high output alternator should be installed for best performance. POWER (+12V) Strip approximately 1/2 inch of insulation from the end of the power cable going to the amplifier. Insert the stripped cable into the power block on the end of the amplifier and tighten the Allen screw. A ring terminal may also be used directly at the power block. Repeat for each amplifier installed. GROUND For low power systems, locate a fairly thick metal area near the amplifier(s). Inspect around and under the chosen area to make sure you wont drill into wires, brake or fuel lines, computers, etc. Remove any paint and carpet glue to a spot approximately 1 inch in diameter. Drill a hole into the middle of this area. Cut a length of ground cable long enough to go from the ground point to the amplifier. Terminate the ground cable with a ring connector and attach it

SYSTEM DIAGRAM 1

Basic Biamp System: Dual 2 Channel Amplifiers D7 two channel amplifier Source: Front RCA outputs ? Channels 1/2 Highpass to a pair of components D7 two channel amplifier Source: Rear outputs ? Channels 1/2 Lowpass to a bridged 4 Ohm subwoofer
D7152 and D7402 manual #135.p8/30/2002, 2:33 PM

SYSTEM DIAGRAM 2

Four Channel System with Subwoofer and Biamplified Front Stage D7 two channel amplifier ? Source: Front RCA outputs ? Channels 1/2 Highpass to tweeters ? AUX. OUTPUTS to 2nd D7 amplifier D7 two channel amplifier ? Input: AUX. OUTPUT (full range) from D7 tweeter amplifier ? Channels 1/2 Bandpass to a pair of midbass drivers D7 two channel amplifier ? Source: Rear RCA outputs ? Channels 1/2 Highpass to a pair of rear fill coaxial components D7 two channel amplifier ? Source: Subwoofer RCA outputs ? Channels 1/2 Lowpass to a pair of bridged 8 Ohm subwoofers
INSTALLATION TOOLS NEEDED FOR INSTALLATION 1/16" Allen Key (Included): Crossover Security Cover Top Screws 3/16" Allen Key: Up to 1/0 AWG Power Rings, Power / Ground 5/32" Allen Key: Up to 4 AWG Direct Input, Power / Ground 1/8" Allen Key: Up to 8 AWG Speaker and Remote Terminal (Also Accepts Banana Jacks) 7/64" Allen Key: Amplifier Mounting Flanges

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A WORD ABOUT PROFESSIONAL INSTALLATION We, the folks at Diamond Audio, highly advise the use of a factory authorized installation technician. System performance ultimately depends on proper installation. Your D7 Series amplifier is an awesome component that deserves to be professionally installed. If this last-chance plea for dealer assistance doesnt sway you, the following instructions will make the installation of your new amplifier a little easier. Before starting your installation, remove the negative battery cable before working on the positive terminal to prevent a short to ground. If a short does occur, current will continue to flow until the short is opened, the main fuse blows, or the wire melts (possibly taking out any nearby flammable object, wire loom, etc. causing a fire or possibly even a tear in the fabric of time and space). Reconnect the negative terminal after all connections have been made. MOUNTING YOUR AMPLIFIER WARNING AMPLIFIERS GENERATE HEAT! You can mount your amplifier in any position, even upside down. However, airflow must be maintained. Do not install your amplifier under carpets or behind airtight panels. Let the amplifier breathe. Without air circulation, your amplifier will reduce its power output to protect itself. D7 Professional Reference Amplifiers utilize a forced-air cooling system. Care must be taken to provide a sufficient flow of air around the amplifier for the thermal management system to operate at peak efficiency. Air is drawn into the system along the sides of the amplifier, over the circuit board, through the bottom heat sink and is exhausted through the vents on the end panels. Be sure to allow at least 2 inches of space around the amplifier. Never mount your amplifier where it can get wet. Water damage is not covered by the

D7152 and D7402 manual #135.p8/30/2002, 2:34 PM
CONTINUOUS RMS OUTPUT POWER Note: Full Rated Power is generated at all voltages between 11 and 16VDC. D7152 150W x 2 @ 4 Ohm Stereo 300W x 2 @ 2 Ohm Stereo 600W Bridged @ 4 Ohms (minimum impedance) D7402 400W x 2 @ 4 Ohm Stere 800W x 2 @ 2 Ohm Stereo 1600W Bridged @ 4 Ohms (minimum impedance)

SYSTEM DIAGRAM 3

Two Channel System Using a Three-Way Component Set D7402 two channel amplifier ? Channels 1/2 full range to a three-way component set with passive crossovers
CROSSOVER SPECIFICATIONS Quantity: Type: Slope: Alignment: 2 (1 for CH 1/2 INPUT, 1 for X-OVER OUT) Fully Independent and Selectable Highpass, Lowpass, Bandpass or All-pass Third Order 18dB/Octave Butterworth FUSE RECOMMENDATIONS D7 Professional Reference Series Amplifiers, by design, require external fusing. Research has shown that a circuit board mounted fuse can create a drop in available DC voltage at the input of the power supply resulting in increased current draw. We recommend that you install the correct size fuse/holder combination to the main power cable within 18 inches of the battery. This will protect your vehicle from fire damage due to a short circuit to the chassis or vehicle body. If a single amplifier is installed, follow the fuse recommendation below. If installing multiple amplifiers, add up the total fuse ratings of all installed amplifiers. This should be used as your main fuse rating.

Amplifier D7152 D7402

Maximum Fuse Rating 80 150
Note: A main fuse must be installed within 18 inches of the positive battery terminal.
D7152 and D7402 manual #135.p8/30/2002, 2:36 PM

SYSTEM DIAGRAM 4

Two Channel System with Three Bridged Amplifiers D7 two channel amplifier ? Channels 1/2 Highpass & Bridged to a component set using Front Left RCA and Rear Left RCA from source unit or EQ D7 two channel amplifier ? Channels 1/2 Highpass & Bridged to a component set using Front Right RCA and Rear Right RCA from source unit or EQ D7 two channel amplifier ? Channels 1/2 Lowpass using Subwoofer RCA outputs from source unit or EQ to a pair of bridged 8 Ohm subwoofers
FEATURES: TECHNICAL Symmetrical Topology, Fully Regulated, Triple-Split-Rail Power Supply Isolated Input Section Utilizing Quasi-Differential Instrumentation Amplifier Technology Up To 12VRMS Input Signal Voltage Capability (With -12dB Attenuator) Third-Order 18dB/Octave Butterworth Crossover Topology Wide Bandwidth/Low Distortion Symmetrical Gain Output Stage 4 oz. (3 oz. on D7152) Gold Plated Copper Circuit Board High Efficiency Forced-Air Cooling System Massive 3-Piece Proprietary Heatsink Solid Copper High-Current Power Distribution Busbars

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CONVENIENCE/APPEARANCE Two 3-Way Fully Variable and Independent Electronic Crossovers in Top-Mount Configuration with Supplied Plexiglass Security Cover (Separate Independent Crossover for RCA Outputs) 24-Karat Gold Plated Solid Brass, Circuit Board Mounted, 4 Gauge Direct or Ring Terminal Power/Ground Connector Blocks 24-Karat Gold Plated Solid Brass, Circuit Board Mounted, 10 Gauge Direct or Banana Plug Direct Speaker Connectors Tinted Plexiglas Circuit Board Viewing Panel Solid Billet CNC Machined End Panels with Adjustable Mounting Flanges
SPECIFICATIONS Frequency Response: Signal-to-Noise Ratio: THD: Channel Separation: Input Sensitivity: Input Impedance: Power Supply Operating Range: 3 50,000 Hz 96dB (D7152), 102dB (D7402) 0.02% 80dB.5 to 12VRMS >40kOhms 10 to 16VDC
DIMENSIONS D7152 Dimensions Length: 17 3/4" Width: 10 5/8" Height: 3" D7402 Dimensions Length: 24 3/4" Width: 10 5/8" Height: 3"
D7152 and D7402 manual #135.p8/30/2002, 2:37 PM

Talk Audio - DLS Ultimate A4 The Big Four

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DLS Ultimate A4 The Big Four

Amplifiers Four Channel

Written by Adam Rayner Wednesday, 23 July 2008

Editor's rating

Reviewed by: Adam Rayner Wednesday, 23 July 2008

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out of 10

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- 4 x 220w RMS @ 1 Ohm - 2 x 250w RMS @ 4 Ohms bridged - 2 x 400w RMS @ 2 Ohms bridged - Extruded brushed gunmetal coloured Aluminium heatsink with Aluminium plate end pieces and steel plate base. Power & Protect LEDs - Dual sets of 4Ga. Gold Plated power terminals with Allen headed grub screw connection, encapsulated in clear Acrylic housings, with second remote terminal used to drive optional fan - 4Ch RCA input on high grade discrete gold plated panel mounted sockets with prophylactic dust covers until use - Subsonic filter function possible by setting HP filter to 20Hz - Front Crossovers: Lowpass 50Hz to 125Hz, Highpass 20Hz to 200Hz or 60Hz to 600Hz by 3x button, all @ 12dB per Octave - Rear Crossovers: Lowpass 45Hz to 200Hz or 90Hz to 400Hz by 2x button, Highpass 20Hz to 200Hz, all @ 12dB per Octave - Input sensitivity: 02V to 7.0V - Stereo & bridged operation - Frequency response not quoted - Signal to Noise Ratio >100dB - Channel separation not quoted - Fuse Rating 150A x 1 by very close external fuse & holder no internal fuse fitted like JL Audio 300/4v2- HxWxD(mm) 73 x 465 x 240mm - Supplied with Swedish/English detailed whole-range manual and electronics components list
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Editor review : DLS Ultimate A4 The Big Four
To the uninitiated, referring to an amplifier for a car that costs a cool eight hundred smackers, as being Good Value for Money (as I am with its nine out of ten VFM rating) might seem bonkers. But consider that for Audison, with their Thesis range, posh can go all the way up to 3,000 for a stereo amplifier and dont get me started on Krell or Class in home amplifiers, as the skys the limit. So why can an amplifier cost so ruddy much? Well its about the zone where mere electronic design is transcended by artistry. At this level stuff isnt just designed by a clever fellow and sent into production, this equipment gets listened to by those with known good ears to see if electronic component choices make for the right results. The differences might seem small but if you were played a commodity-type amplifier and then A/Bd to another rig, identical but for a much better amp, you would of
OVERALL RATING SOUND QUALITY POWER OUTPUT FEATURES BUILD QUALITY VALUE FOR MONEY 9.6 10.0 10.0 9.0 10.0 9.0
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course hear the difference. Even if the rigs had been sound pressure level matched, so that louder was not just better. This product is about Real HiFi for cars. Its for those who want the best sound and know that the logarithm is badly against them. Making something to go boom is one thing but making super quality sonics is a lot more challenging. Diamond Audios D7 was 2,500 and the DLS vacuum tube preamplified product, the TA2 is priced at 1,500. So for what this actually is, it represents high end VFM! I loved its posh construction, right down to the smooth-as-a-piston-in-a-well-lubed-pot manner in which the RCAs penises penetrated the solid Teflon dielectric RCA panel sockets. They intromitted perfectly. Like the Tru Technologies Steel 44, this amplifier does feel like it could benefit from a stonkerating high resolution signal from a pukka line driver once up and running on the test rig but it worked well on the signal I was able to muster. Immediately the delicious levels of detail, sweetness and terribly fast resolution of those oh so important high frequency/high rise time sonic components was right in your face. If the Tru Technology Steel 44 played the Morel Supremo 6 speakers well, this amplifier was awesome and made you see why the speakers were 1,400 a set. The amplifier wasnt just superbly clean and pleasant, it was also able to go loud as well, with a creditable 125.4dB raised; measured via the SPL side of the AudioControl SA-3055 RTA that we use to check stuff out. Not just made to go loud, its about the scale of things, you can hear the size of the sound stage even at sensible or lowish levels as the headroom is just enormous. This headroom also makes for vast dynamism with the sound able to go from clear and pleasantly restful to major emotional impact and goose bumps in a fragment of a second. I found myself just simply enjoying the test disc yet again, when I should have been getting on with fitting the next amplifier to the rig. The crossovers are comprehensive, clever, wide ranging and intelligently designed. It doesnt feature a whole load of extra silliness, just the best of what DLS reckon really matters and these work very well and are clearly intended to be used, and not just put there as some punters might complain if they were not present. A completely brilliant single footprint four corner solution for an utterly audiophillic installation and scores so brilliantly in so many directions (including that crucial VFM thing) that is garners only our second ever audio-based State of the Art award. This product is everything it claims to be and makes me feel good that it even exists. Sonic excellence on the Hoof!