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We currently have this product in stock and available for dispatch.
Stock Location
| AV Distribution Hub: | 1 |
"Get it" shows the next available date that we will be able to deliver this item to you on, depending on the delivery option you select, and the stock availability of anything else that you add to your shopping basket.
5-year warranty & 30-day money-back guarantee included
If you decide your order isn't suitable for any reason you can return it - just let us know within 30 days of receiving it. Please keep hold of all the original packaging until you're sure you want to keep the order.
Eligibility for Money Back Guarantee
Important: For hygiene and software licensing reasons, some items are only eligible for our Money Back Guarantee if they are returned to us unused and sealed in the original packaging with all software still "unregistered." Details of exclusions are shown within the product descriptions. Products include:
- Monitors and Headphones
- Earplugs and Ear Protection
- Reeds and mouthpieces for woodwind and brass instruments
- Mouth and Lip-Care Products
- CDs, DVDs and Software
We can collect your return for a small fee, or you can send it back to us yourself. The collection fee can be found in the returns information on each product's page on AV.com.
In the unlikely event that any item in this order is faulty, damaged or incorrect on receipt, notify us within 14 days and we'll arrange a free collection.
When returning an order please ensure products are appropriately packaged and protected, to prevent them from getting damaged.
This table provides an overview of your statutory consumer rights, compared with our standard returns policy and optional extended money back guarantee and warranty.
| UK & Europe | EU Standard | AV.com Standard | AV.com Optional |
|---|---|---|---|
| Return Period | 14 days | 30 days | up to 180 days |
| Standard delivery charges refunded? | Yes | Yes | Yes, up to 30 days |
| Upgraded delivery charges refunded? | Standard costs only | Standard costs only | Standard costs only |
| Free collection on cancellation | No | No | Yes, up to 30 days |
| Free collection if defective, delivered damaged or incorrect item | Yes, within 14 days | Yes, within 14 days | Yes, within 30 days |
We are unable to accept returns of any custom made items designed to work together as a unique package and some items are only eligible for money back guarantee if they are returned to us unused and sealed in the original packaging. For full information on our returns policy, please refer to our returns and refunds information guide.
10-year warranty & 180-day money-back guarantee included
If you decide your order isn't suitable for any reason you can return it - just let us know within 30 days of receiving it. Please keep hold of all the original packaging until you're sure you want to keep the order.
Eligibility for Money Back Guarantee
Important: For hygiene and software licensing reasons, some items are only eligible for our Money Back Guarantee if they are returned to us unused and sealed in the original packaging with all software still "unregistered." Details of exclusions are shown within the product descriptions. Products include:
- Monitors and Headphones
- Earplugs and Ear Protection
- Reeds and mouthpieces for woodwind and brass instruments
- Mouth and Lip-Care Products
- CDs, DVDs and Software
We can collect your return for a small fee, or you can send it back to us yourself. The collection fee can be found in the returns information on each product's page on AV.com.
In the unlikely event that any item in this order is faulty, damaged or incorrect on receipt, notify us within 14 days and we'll arrange a free collection.
When returning an order please ensure products are appropriately packaged and protected, to prevent them from getting damaged.
This table provides an overview of your statutory consumer rights, compared with our standard returns policy and optional extended money back guarantee and warranty.
| UK & Europe | EU Standard | AV.com Standard | AV.com Optional |
|---|---|---|---|
| Return Period | 14 days | 30 days | up to 180 days |
| Standard delivery charges refunded? | Yes | Yes | Yes, up to 30 days |
| Upgraded delivery charges refunded? | Standard costs only | Standard costs only | Standard costs only |
| Free collection on cancellation | No | No | Yes, up to 30 days |
| Free collection if defective, delivered damaged or incorrect item | Yes, within 14 days | Yes, within 14 days | Yes, within 30 days |
We are unable to accept returns of any custom made items designed to work together as a unique package and some items are only eligible for money back guarantee if they are returned to us unused and sealed in the original packaging. For full information on our returns policy, please refer to our returns and refunds information guide.
The product price includes 5 years' warranty and 30 day money back guarantee.
However, the AV.com extended warranty scheme provides an enhanced service, and is designed to offer a higher level of protection than many 'free' warranties offered by some retailers and manufacturers.
The highlights of this enhanced warranty service are:
Please note that this extended warranty is currently only available on products sold within the UK, EU or EEA, and is subject to the terms and conditions as detailed on the extended warranty certificate provided.
For customers in outlying areas of the country, the price of the Extended Warranty may be marginally higher, due to the potential for higher collection and redelivery transport costs.
This enhanced warranty is in addition to the standard AV.com and manufacturer warranty policies, and the AV.com terms and conditions of trade. No statement or condition of sale contained within these terms affects or restricts your statutory rights as defined under the Consumer Contracts Regulation 2014.
Finance from £96.40 per month (14.9% APR Representative)
Buy on finance from £96.40 per month Finance from £96.40 per month
Please note: This is only available where all items in the order are dispatched in a single delivery. Gear4music Ltd is authorised and regulated by the Financial Conduct Authority ("FCA) (FCA FRN 706272) and acts as a credit intermediary and not a lender, offering credit products provided by a limited number of finance providers, including Klarna Financial Services UK Limited (company number 14290857), which is authorised and regulated by the FCA for carrying out regulated consumer credit activities (firm reference number 987889), and for the provision of payment services under the Electronic Monday Regulations 2011 (firm reference number 1021834).
More infoTo make it as easy as possible for you to get the gear you want, we offer a range of instant finance options. If you spend £250 or more online, you can choose to pay over 12, 24, 36 or 48 months. The majority of decisions are given instantly, so you could get your new gear sooner than you thought!
Representative Example
To help you understand how our finance options work, the examples below are based on a total order value of £250:
| Finance | APR Rep. | Deposit to Pay | Payments | Total Payable |
|---|---|---|---|---|
| 12 months | 21.90% | £25.00 | 12 months: £21.51Final Payment: £21.51No settlement fee | £283.12 |
| 24 months | 21.90% | £25.00 | 24 months: £11.92Final Payment: £11.92No settlement fee | £311.08 |
| 36 months | 21.90% | £25.00 | 36 months: £8.77Final Payment: £8.77No settlement fee | £340.72 |
| 48 months | 14.90% | £25.00 | 48 months: £6.34Final Payment: £6.34No settlement fee | £329.32 |
How to Apply
Applying for finance couldn't be easier - if your order totals £250 or more, simply proceed through the checkout as normal. If your order qualifies, during the Payment step you'll see options available underneath the Flexible Payment Options heading. Select your preferred option and then click the orange PLACE ORDER USING FINANCE button. This will start your application with our finance partners. Completing this form should take approximately 10 minutes.
You should get an instant answer on whether your application has been successful, though in some rare cases our finance provider may need to look at the application in more detail.
Please note: This is only available on orders placed via the website consisting of a single delivery, and is not available in store or via phone currently. Warranties can not be purchased on finance. If you wish to purchase warranties, please choose another payment method or contact us after placing your order and we'll be happy to help you. Additionally, please note that software downloads are subject to a £300 maximum spend.
To make it as easy as possible for you to get the gear you want, we offer a range of instant finance options. If you spend £250 or more online, you can choose to pay over 12, 24, 36 or 48 months. The majority of decisions are given instantly, so you could get your new gear sooner than you thought!
Representative Example
To help you understand how our finance options work, the examples below are based on a total order value of £250:
| Finance | APR Rep. | Deposit to Pay | Payments | Total Payable |
|---|---|---|---|---|
| 12 months | 21.90% | £25.00 | 12 months: £21.51Final Payment: £21.51No settlement fee | £283.12 |
| 24 months | 21.90% | £25.00 | 24 months: £11.92Final Payment: £11.92No settlement fee | £311.08 |
| 36 months | 21.90% | £25.00 | 36 months: £8.77Final Payment: £8.77No settlement fee | £340.72 |
| 48 months | 14.90% | £25.00 | 48 months: £6.34Final Payment: £6.34No settlement fee | £329.32 |
How to Apply
Applying for finance couldn't be easier - if your order totals £250 or more, simply proceed through the checkout as normal. If your order qualifies, during the Payment step you'll see options available underneath the Flexible Payment Options heading. Select your preferred option and then click the orange PLACE ORDER USING FINANCE button. This will start your application with our finance partners. Completing this form should take approximately 10 minutes.
You should get an instant answer on whether your application has been successful, though in some rare cases our finance provider may need to look at the application in more detail.
Please note: This is only available on orders placed via the website consisting of a single delivery, and is not available in store or via phone currently. Warranties can not be purchased on finance. If you wish to purchase warranties, please choose another payment method or contact us after placing your order and we'll be happy to help you. Additionally, please note that software downloads are subject to a £300 maximum spend.
Key Features
The Astell&Kern A&ultima SP4000 is designed for those who value uncompromising audio quality, elegant design, and smooth day-to-day usability. It's a flagship digital audio player that combines precision engineering with a refined user experience, perfect for discerning listeners, whether you're enjoying hi-res tracks at home or streaming on the move.
With a completely reworked internal architecture and a high-performance processor, the SP4000 delivers outstanding sonic clarity, low distortion, and exceptional control. You can explore your music collection with greater depth and detail, all housed in a body crafted from premium stainless steel and wrapped in a luxury leather case.
Product Ref: 365292
Get a free premium leather SP4000 case when you purcahse this bundle
The SP4000 introduces a true Octa audio circuit with a 1:1 pairing of digital processors and DACs—delivering one of the cleanest signal paths ever seen in a portable player. This refined layout eliminates the need to split signals between multiple channels, significantly reducing noise and distortion. What you get is sound that’s vivid and spatially precise. It allows every note, texture, and nuance to come through with startling realism—especially noticeable in complex recordings with layered instruments and wide dynamic range.
To get the most out of your headphones—especially high-impedance models—the SP4000 features High Driving Mode. By doubling the number of OPAMPs and running them in parallel, this mode delivers robust, stable power with no increase in noise. That means you’ll hear deeper bass, more open mids, and shimmering treble, all with excellent control. It’s a feature that ensures your music sounds dynamic and alive, whether you're listening at low volume or pushing your headphones to their full potential.
With full Android OS integration, the SP4000 offers a smooth and familiar interface, giving you access to your favourite streaming services. But it doesn’t stop there. Astell&Kern’s bespoke ADP (Direct Path) system bypasses Android’s built-in sample rate conversion, enabling bit-perfect playback—even when streaming. You can enjoy studio-quality sound from TIDAL, Qobuz, or your preferred app, without compromise. It blends high-end performance with the convenience of wireless listening, making the SP4000 ideal for modern audiophiles who still demand top-tier sound.
Group delay—where different frequencies arrive at your ears out of sync—can blur the soundstage and reduce clarity. The SP4000’s proprietary ESA (Enhanced Signal Alignment) technology addresses this by ensuring more consistent timing across the frequency range. The result is purer, more transparent playback, especially noticeable in acoustic recordings, vocals, and live performances. With ESA, the sound feels more coherent and lifelike, helping instruments retain their character and separation, while reducing the smearing that can affect complex tracks.
The SP4000 is constructed from 904L stainless steel—a premium material typically used in high-end watches. It’s more durable and corrosion-resistant than standard stainless steel, and its polished finish adds a premium touch that lasts. A matching case made from Perlinger’s Shrunken Calf leather complements the design beautifully. Known for its softness, grain, and resilience, this German leather ages gracefully over time. Together, these materials elevate the SP4000 beyond electronics—this is a personal object built to perform and endure.
Everyone listens differently—and the SP4000 embraces that. It includes six user-selectable DAC filters, allowing you to adjust the sound character to your liking. Whether you prefer the laid-back warmth of a slow roll-off filter or the sharper edge of a fast roll-off setting, the player gives you full control. It’s a subtle but rewarding feature, especially for those who enjoy fine-tuning their sound based on music style or mood. With each filter, you shape the sonic signature to reflect your own taste.
| Model | SP4000 (PPF51) |
|---|---|
| Body Color | Black |
| Body Material | Stainless Steel 904L |
| Display | 6inch 2K (2160 x 1080) touch screen |
| Supported Audio Formats | WAVFLACWMAMP3OGGAPEAACALACAIFFDFFDSF |
| Sample rate | PCM : 8kHz 768kHz (8/16/24/32bits per Sample) |
| DSD Native | DSD64(1bit 2.8MHz), StereoDSD128(1bit 5.6MHz), StereoDSD256(1bit 11.2MHz), StereoDSD512(1bit 22.4MHz), Stereo |
| Output Level | Unbalanced 4.1Vrms ? Balanced 8.2Vrms (Condition No Load) |
| CPU | Octa-core |
| DAC | AKM4191 x4 + AKM4499EX x4 (Real Quad DAC) |
| Decoding Support | up to 32bit / 768kHz Bit to Bit playback |
| Input | USB Type-C input (for charging & PC & MAC) |
| Outputs | Unbalanced Out (3.5mm)Optical Out (3.5mm)Balanced Out (4.4mm, only 5-pole supported) |
| Wi-Fi | 802.11 a/b/g/n/ac (2.4/5GHz) |
| Bluetooth | V5.0 (A2DP, AVRCP, Qualcomm® aptX™ HD, LDAC, LHDC, SBC, AAC) |
| Dimensions W x H x D | 85mm x 149.8mm x 19.5mm |
| Weight | 615g |
| Feature Enhancements | Firmware upgrade supported (OTA) |
| Operating Temperature | 0? + 40? (32? 104?) |
| Frequency Response | ±0.006dB (Condition : 20Hz20kHz) Unbalanced ? ±0.006dB (Condition : 20Hz20kHz) Balanced±0.06dB (Condition : 20Hz70kHz) Unbalanced ? ±0.06dB (Condition : 20Hz70kHz) Balanced |
|---|---|
| S/N | 129dB @ 1kHz, Unbalanced ? 131dB @ 1kHz, Balanced |
| Crosstalk | -136dB @ 1kHz, Unbalanced ? -145dB @ 1kHz, Balanced |
| THD+N | 0.0005 @ 1kHz, Unbalanced ? 0.0003 @ 1kHz, Balanced |
| IMD SMPTE | 0.0004 800Hz 10kHz (4:1) Unbalanced ? Balanced |
| Output Impedance | Unbalanced Out 3.5mm (0.7ohm) ? Balanced Out 4.4mm (1.7ohm) |
| Clock Jitter | 25pS (Typ) |
|---|---|
| Reference Clock Jitter | 200 Femto Seconds |
| Built-in Memory | 256GB [NAND] |
|---|---|
| External Memory | microSD x1 (Max. 1.5TB) |
| Capacity | 6,780mAh 3.8V Li-Polymer |
|---|---|
| Charge Time | about 5hours (QC3.0 Charging) |
| Playback Time | about 10hours (Standard : FLAC, 16bit, 44.1kHz, Vol.50, LCD Off) |
| Supported OS | Windows 10,11(32/64bit)MAC OS X 10.7 |
|---|
| Product code | AKP23 |
|---|---|
| EAN | 8800309909057 |
