Audio T Verdict
The Sugden Sapphire DAP-800 is designed to become the control centre of a serious digital and analogue Hi-Fi system.
Its analogue and digital sections operate independently, with separate power supplies and dedicated signal circuits. In effect, Sugden has placed a high-quality analogue preamplifier and the conversion technology from its standalone DAC-4 inside one substantial chassis.
With four RCA line inputs, balanced analogue input, home-cinema bypass, six digital connections and three variable preamplifier outputs, the DAP-800 can accommodate an extensive system. Its USB specification is relatively modest by modern standards, but the coaxial and optical inputs support up to 24-bit/96kHz and the analogue stage remains the real star of the design.
Sugden Sapphire DAP-800 Digital Analogue Pre-Amplifier
The Sugden Sapphire DAP-800 combines an analogue preamplifier and digital-to-analogue converter within one handmade British component.
It provides volume control and source selection for conventional analogue equipment while also converting compatible digital signals from CD transports, network streamers, televisions, computers and other digital sources.
The DAP-800 can be connected to a stereo power amplifier, two power amplifiers, compatible active loudspeakers or a power amplifier and active subwoofer.
Analogue and Digital Control Centre
The DAP-800 provides an unusually extensive range of connections for both analogue and digital source equipment.
Its rear panel includes six analogue connections:
- Four stereo RCA line-level inputs
- One stereo balanced XLR input
- One stereo bypass input
Six digital connections are also provided:
- Three coaxial S/PDIF inputs
- Two optical S/PDIF inputs
- One USB Type B input
Separate front-panel selectors are provided for the analogue and digital sections.
Separate Analogue and Digital Domains
Sugden has designed the DAP-800 to operate in two separate electrical domains.
The analogue preamplifier and digital conversion circuits have independent power supplies rather than sharing one common supply between them.
This helps reduce the opportunity for switching noise and other electrical activity from the digital section to interfere with the low-level analogue signal path.
Independent Power Switching
The analogue preamplifier and digital converter have separate mains switching arrangements.
The front-panel power control operates the preamplifier section, while a separate switch on the rear panel controls the digital circuit.
This allows the digital section to be switched off when only analogue sources are being used.
Advanced Sugden VCV Circuit
The DAP-800’s analogue stage uses Sugden’s VCV preamplifier circuit in its most advanced form.
The circuit begins with a high-impedance input section, followed by a current-gain stage that drives a folded-cascode circuit and Class A output stage.
This arrangement is designed to provide wide bandwidth, strong dynamic performance and low capacitive loading between connected components.
Class A Analogue Output Stage
The final stage of the DAP-800’s analogue preamplifier operates in Class A.
Class A operation keeps the active devices continuously conducting rather than switching between different operating states as the music signal changes.
The circuit is designed to provide a transparent and neutral connection between the selected source and the power amplifier.
Folded-Cascode Circuit
The folded-cascode stage allows the preamplifier to achieve wide bandwidth while keeping the signal path responsive to small and fast musical changes.
Sugden uses this topology to combine current gain with a low-capacitance connection into the Class A output stage.
The design is intended to preserve dynamics and detail without adding unnecessary tonal character.
Four RCA Line-Level Inputs
Four stereo RCA inputs are provided for conventional line-level source components.
Compatible sources can include:
- CD and SACD players with analogue outputs
- Network music streamers
- External digital-to-analogue converters
- Radio tuners
- Cassette decks and other recording equipment
- Turntables used with a separate phono stage
The inputs are intended for conventional line-level signals and should not receive the direct output of a phono cartridge.
Balanced XLR Analogue Input
One stereo balanced XLR input allows a compatible source component to be connected using balanced interconnects.
Balanced connections can provide improved rejection of electrical interference, particularly when longer cable runs are required or when a system contains several mains-powered components.
The connected source must provide a compatible balanced analogue output.
No Internal Phono Stage
The DAP-800 does not include an internal moving-magnet or moving-coil phono stage.
A conventional turntable must be connected through a suitable external phono amplifier, such as the Sugden Masterclass PA-4.
The line-level output from the phono stage can then be connected to one of the DAP-800’s RCA or compatible balanced analogue inputs.
Connecting a Turntable
Do not connect a turntable cartridge directly to one of the DAP-800’s line inputs.
The cartridge signal requires additional gain and RIAA equalisation from a compatible moving-magnet or moving-coil phono stage.
Audio T can help match the phono stage to your cartridge, turntable and DAP-800.
Home-Cinema Bypass Input
A dedicated bypass input allows the DAP-800 and its connected power amplifier to become part of a compatible home-cinema system.
When the DAP-800 is switched off, the bypass input passes the incoming signal to the RCA preamplifier outputs at its original level.
This allows an AV processor or home-cinema amplifier to control the volume of the front left and right speakers during film playback.
When the DAP-800 is switched on, the bypass input is muted.
Bypass Input Warning
The bypass input does not use the DAP-800’s volume control while the preamplifier is switched off.
Only connect it to a compatible AV processor or other source with its own properly controlled variable output.
Connecting a conventional fixed-level source to the bypass input could send an excessively high signal directly to the power amplifier and loudspeakers.
Six Digital Connections
The DAP-800 provides three coaxial, two optical and one USB Type B digital input.
These connections allow compatible digital source components to use the DAP-800’s internal conversion circuit rather than their own analogue output stages.
A front-panel digital selector chooses the required digital source independently of the analogue input selector.
Three Coaxial S/PDIF Inputs
Three RCA coaxial S/PDIF inputs are provided for compatible CD transports, network players, televisions and other digital source equipment.
Sugden specifies digital word lengths up to 24-bit and sample rates up to 96kHz through the main digital interface.
A purpose-designed 75-ohm coaxial digital cable should be used rather than one half of a normal stereo analogue interconnect.
Two Optical S/PDIF Inputs
Two optical inputs allow compatible digital sources to be connected using Toslink cables.
Optical transmission provides electrical isolation between the source and preamplifier, which can be useful when connecting televisions, computers or other equipment that may introduce unwanted electrical noise.
The connected source must be configured to output a digital format supported by the DAP-800.
USB Type B Input
The USB Type B input provides a plug-and-play connection for a compatible computer, media player or dedicated streaming source.
Once connected, the DAP-800 may need to be selected as the audio-output device within the computer’s operating-system or playback-software settings.
Sugden specifies the USB input at up to 16-bit/44.1kHz.
USB Resolution
The USB input is limited to 16-bit/44.1kHz and should not be assumed to support modern high-resolution USB formats.
Higher-resolution compatible sources can use one of the coaxial or optical S/PDIF inputs at up to 24-bit/96kHz.
Digital-Lock Indicator
A digital-lock indicator is located on the front panel.
The indicator illuminates when the DAP-800 detects and locks onto a compatible incoming digital signal.
If the indicator does not illuminate, check the selected input, source output setting, cable connection and digital format.
Conversion Technology From the Sugden DAC-4
The DAP-800 uses the same digital-to-analogue conversion approach as Sugden’s standalone Masterclass DAC-4.
This allows digital sources to benefit from a dedicated conversion section before their analogue signal reaches the DAP-800’s preamplifier and Class A output stage.
The analogue and digital circuits remain independently powered within the shared chassis.
Dedicated Digital Transceiver
A dedicated transceiver circuit receives and reformats incoming digital data before it reaches the digital-to-analogue converter.
Sugden uses this stage to reduce timing errors and jitter during playback.
The circuit is designed to present the converter with a more consistent digital data stream from compatible connected sources.
No Digital Oversampling
The DAP-800 does not use oversampling within the digital domain.
Sugden has chosen a conversion method that avoids digital-domain oversampling and filtering before the signal is converted into analogue form.
This reflects the company’s preference for a direct digital conversion approach rather than extensive digital signal processing.
Analogue Output Filtering
Instead of applying filtering within the digital domain, the DAP-800 uses an analogue filter after conversion.
Sugden states that this arrangement contributes to the converter’s wide bandwidth capability and natural analogue presentation.
No user-selectable digital-filter modes are listed.
Two RCA Preamplifier Outputs
Two pairs of variable stereo RCA preamplifier outputs are provided.
One pair can be connected to a conventional stereo power amplifier, while the second pair can supply another compatible power amplifier or an active subwoofer.
Both outputs follow the setting of the DAP-800’s main volume control during normal preamplifier operation.
Connecting an Active Subwoofer
The second RCA preamplifier output can be connected to a compatible active subwoofer.
The subwoofer must contain its own amplifier and provide suitable level and crossover controls.
The DAP-800 supplies a full-range variable signal, so bass filtering and integration are normally adjusted using the controls on the subwoofer.
Balanced XLR Preamplifier Output
One stereo balanced XLR output is provided for connection to a compatible power amplifier or active loudspeaker system.
This is particularly well suited to Sugden power amplifiers offering balanced inputs, including models within the Sapphire and Masterclass ranges.
Balanced operation can be useful where the power amplifier is positioned further away from the DAP-800 or where improved rejection of electrical interference is required.
Fixed Tape Output
A fixed-level tape output is provided for a compatible recording device or other line-level component.
The tape output does not follow the DAP-800’s main volume setting.
It should not be connected directly to a power amplifier or active loudspeakers unless the receiving equipment provides its own reliable volume control.
Motorised Analogue Volume Control
The DAP-800 uses a motorised analogue volume control rather than adjusting volume through digital signal processing.
The level can be changed using the front-panel control or supplied remote-control handset.
Sugden specifies an input sensitivity of 120mV for an output of 1V and a maximum output level of 9V.
RC5-Compatible Remote Control
A remote-control handset is supplied with the DAP-800.
The preamplifier functions programmed into the handset are volume up and volume down.
Analogue and digital input selection remain controlled from the front panel.
A Separate Power Amplifier Is Required
The DAP-800 is a preamplifier and DAC. It does not contain the power-amplifier stage required to drive conventional passive loudspeakers.
It must be connected to a compatible stereo power amplifier, pair of monoblock power amplifiers or active loudspeaker system.
The Sugden Sapphire FBA-800 is the matching power amplifier within the Sapphire range.
Pre and Power System Matching
The power amplifier must be compatible with the DAP-800’s output level and connection type.
Audio T can advise whether RCA or balanced XLR is the best connection and help match the preamplifier, power amplifier and loudspeakers as a complete system.
Not a Network Music Streamer
The DAP-800 contains digital inputs and a DAC but does not provide built-in Wi-Fi, Ethernet, Bluetooth, music-service apps or network-library browsing.
A separate network streamer is required for services such as internet radio or app-controlled music playback.
The streamer can be connected digitally through coaxial, optical or compatible USB, or through one of the DAP-800’s analogue inputs.
Wide Analogue Bandwidth
Sugden publishes a frequency response of 15Hz to 98kHz at 0dB.
The wider published bandwidth extends from 8Hz to 125kHz.
This allows the analogue preamplifier to maintain consistent behaviour throughout and beyond the conventional audible frequency range.
Greater Than 85dB Signal-to-Noise Ratio
The DAP-800 has a published signal-to-noise ratio greater than 85dB.
The final system noise level will also depend on the selected source, power amplifier, cables, mains environment and equipment-earthing arrangements.
Handmade in West Yorkshire
The DAP-800 is designed and manufactured at Sugden’s factory in Heckmondwike, West Yorkshire.
Sugden continues to hand-build its products rather than relying on high-volume automated production.
This approach allows the company to maintain control over assembly, testing and long-term serviceability.
Installation and Ventilation
The DAP-800 measures 430mm wide, 120mm high and 340mm deep.
It can be positioned on a suitable equipment shelf or within a properly ventilated Hi-Fi cabinet.
Do not place the DAP-800 directly on top of a power amplifier, beside a strong heat source or where its ventilation openings will be obstructed.
Sugden publishes a gross packed weight of 10kg.
Supplied Accessories
- RC5-compatible remote-control handset
- Two AAA batteries
- IEC mains lead with a region-appropriate moulded plug
Key Features
- Digital-to-analogue converter and analogue preamplifier
- Part of the flagship Sugden Sapphire range
- Handmade in Heckmondwike, West Yorkshire
- Separate analogue and digital circuit domains
- Independent analogue and digital power supplies
- Separate analogue and digital mains switching
- Advanced Sugden VCV analogue circuit
- High-impedance analogue input section
- Current-gain stage
- Folded-cascode circuit
- Class A analogue output stage
- Four stereo RCA line-level inputs
- One stereo balanced XLR analogue input
- One home-cinema bypass input
- Three coaxial S/PDIF digital inputs
- Two optical S/PDIF digital inputs
- One USB Type B input
- Up to 24-bit/96kHz through compatible S/PDIF inputs
- USB support up to 16-bit/44.1kHz
- Digital-lock indicator
- Digital conversion technology derived from the Sugden DAC-4
- Dedicated digital transceiver circuit
- Incoming digital-data reformatting
- No digital-domain oversampling
- No digital-domain filtering
- Analogue output filter
- Two variable stereo RCA preamplifier outputs
- One variable stereo balanced XLR output
- One fixed-level tape output
- Second RCA pre-out for another power amplifier or active subwoofer
- Motorised analogue volume control
- RC5-compatible remote volume control
- 120mV input sensitivity for 1V output
- 9V maximum output
- 15Hz to 98kHz frequency response at 0dB
- 8Hz to 125kHz published bandwidth
- Greater than 85dB signal-to-noise ratio
Frequently Asked Questions
What is the Sugden DAP-800?
It is a combined digital-to-analogue converter and analogue preamplifier designed to control digital and analogue sources before sending a variable signal to a power amplifier or active loudspeakers.
Is the DAP-800 an integrated amplifier?
No. It does not contain a power-amplifier stage and cannot drive conventional passive loudspeakers directly.
Does it require a separate power amplifier?
Yes, unless it is being used with compatible active loudspeakers containing their own amplification.
How many analogue inputs are provided?
There are four RCA line inputs, one balanced XLR input and one bypass input.
How many digital inputs are provided?
The rear panel provides six digital connections: three coaxial, two optical and one USB Type B input.
Does the DAP-800 have a built-in DAC?
Yes. Its digital conversion section uses the same approach as Sugden’s standalone DAC-4.
What digital resolution does it support?
Sugden specifies up to 24-bit/96kHz through its main digital interface and up to 16-bit/44.1kHz through USB.
Does it support high-resolution USB audio?
The USB input is limited to 16-bit/44.1kHz. Higher-resolution compatible signals should use coaxial or optical S/PDIF.
Does the DAP-800 support DSD?
Sugden does not list DSD compatibility, so DSD playback should not be assumed.
Does it oversample digital audio?
No. Sugden states that its conversion method does not use oversampling or filtering within the digital domain.
How is the converted signal filtered?
The DAP-800 uses an analogue filter after digital-to-analogue conversion.
What does the digital transceiver do?
It receives and reformats incoming digital data before conversion, helping reduce jitter and playback errors.
What does the digital-lock light mean?
It confirms that the DAP-800 has detected and locked onto a compatible incoming digital signal.
Can I connect a television?
Yes, provided that the television has a compatible optical or coaxial digital output and can be configured to send a format supported by the DAP-800.
Can I connect a CD transport?
Yes. A CD transport can use one of the coaxial or optical S/PDIF inputs.
Can I connect a network streamer?
Yes. A streamer can use a compatible coaxial, optical, USB, RCA or balanced analogue connection.
Does the DAP-800 stream music by itself?
No. It does not contain Wi-Fi, Ethernet, Bluetooth or music-service software. A separate streamer is required.
Does it include Bluetooth?
No Bluetooth facility is listed.
Does it include a phono stage?
No. A separate compatible moving-magnet or moving-coil phono stage is required for a conventional turntable.
Can I connect the Sugden PA-4?
Yes. Connect one of the PA-4’s line-level outputs to an RCA input on the DAP-800.
What is the bypass input for?
It allows a compatible AV processor to send its front-channel signal directly to the DAP-800’s RCA outputs while the preamplifier is switched off.
Does the DAP-800 control volume in bypass mode?
No. The bypass signal passes at its original level, so volume must be controlled by the connected AV processor or source.
What happens to the bypass input when the DAP-800 is switched on?
Sugden states that the bypass input is muted when the preamplifier is switched on.
How many preamplifier outputs are provided?
There are two variable stereo RCA outputs and one variable stereo balanced XLR output.
Can two power amplifiers be connected?
Yes. The two RCA output pairs can be used to supply two compatible power amplifiers.
Can an active subwoofer be connected?
Yes. Sugden states that the second RCA preamplifier output can be connected to a compatible active subwoofer.
Does the subwoofer output have bass management?
No dedicated crossover or bass-management system is listed. Level and crossover filtering should be adjusted on the active subwoofer.
Does the DAP-800 have balanced outputs?
Yes. One stereo balanced XLR preamplifier output is provided.
Does it have a fixed output?
Yes. A fixed-level tape output is included for compatible recording equipment and other line-level applications.
Is the volume control analogue or digital?
It is a motorised analogue volume control.
Does the remote control change inputs?
No. Sugden’s current manual states that the DAP-800 functions programmed into the supplied handset are volume up and down.
Can the digital section be switched off?
Yes. It has a separate rear-panel mains switch, allowing the digital circuit to be switched off when it is not required.
What is the maximum output level?
Sugden publishes a maximum output of 9V.
What is the input sensitivity?
Sugden specifies an input sensitivity of 120mV for an output of 1V.
What is the frequency response?
Sugden publishes a frequency response of 15Hz to 98kHz at 0dB.
What is the published bandwidth?
The published bandwidth extends from 8Hz to 125kHz.
What is the signal-to-noise ratio?
Sugden publishes a signal-to-noise ratio greater than 85dB.
Where is the DAP-800 manufactured?
It is designed and manufactured at Sugden’s factory in Heckmondwike, West Yorkshire.
How large is the Sugden DAP-800?
It measures 430mm wide, 120mm high and 340mm deep.
How much does it weigh?
Sugden publishes a gross packed weight of 10kg.
Related Products and Audio T Guides
Why Buy From Audio T?
- Independent advice from experienced Hi-Fi specialists
- Careful preamplifier and power-amplifier matching
- Balanced XLR and unbalanced RCA connection guidance
- Help connecting digital and analogue source equipment
- External phono-stage and cartridge advice
- Home-cinema bypass setup assistance
- Active-subwoofer integration guidance
- In-store demonstrations at participating branches
- Cable and equipment-support recommendations
- Home demonstrations and product loans where available
- Click and Reserve from participating stores
- Nationwide UK delivery on eligible products
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Contact your local Audio T store to arrange a demonstration or discuss matching the Sugden Sapphire DAP-800 to your power amplifier, sources and loudspeakers.