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SizeStem TERMS OF USE

October 2026

1.1 These Terms govern your installation and use of SizeStem and its updates.

1.2 Read these Terms before accepting them.

1.3 Acceptance requires an affirmative action, such as selecting an agreement checkbox.

1.4 If you do not agree, cancel installation or activation.

1.5 These Terms govern the software licence.

1.6 Your purchase is also subject to the product description, checkout information and applicable seller terms supplied with your order.

1.7 Nothing in these Terms excludes or restricts rights that applicable law does not permit us to exclude or restrict.

1.8 Installation requires explicit acceptance of these terms.

2.1 SizeSynth, we and us mean the supplier identified in section 20.

2.2 Software means the SizeStem standalone audio separation application, including its supplied documentation and updates.

2.3 Named licensee means the individual to whom a SizeStem licence is granted.

2.4 Licence unit means a purchased unit of SizeStem licence capacity, providing two registered computer slots for the same named individual.

2.5 Account means the SizeSynth account associated with the named licensee and their purchased entitlement.

2.6 Your material means the audio, recordings, projects and resulting output in which you hold the relevant rights.

2.7 Website means https://sizesynth.com.

3.1 SizeStem is a standalone audio separation application producing vocals, drums, bass, guitar, piano and other stems.

3.2 A and B use different separation approaches.

3.3 Dual produces two versions of each stem for independent A/B comparison.

3.4 Processing time and results depend on the recording and computer.

3.5 No separation approach guarantees superior results or faster processing for every track.

4.1 Your paid licence starts on the purchase date shown on your receipt.

4.2 Each paid licence unit grants one named individual a limited, non-exclusive, non-transferable lifetime licence to use SizeStem in accordance with these terms, including future SizeStem updates, on two computers.

4.3 Unlimited SizeStem instances are permitted on either licensed computer.

4.4 This is a one-time purchase with no recurring subscription or offline-authorisation renewal charge.

4.5 The licence is revocable only on the lawful breach and termination grounds in these terms or as required by applicable law, not at SizeSynth.com's unrestricted discretion.

4.6 Additional units add two computer slots each for the same individual.

4.7 Employer payment does not authorise shared accounts, team use or additional users.

4.8 Every other user requires a separate licence and account.

4.9 The licence covers SizeStem only and does not grant access to another SizeSynth.com product.

4.10 The named licensee may use both licensed computers simultaneously within the purchased allowance.

5.1 Permitted use is personal and commercial audio processing by the named licensee on licensed computers within the purchased allowance.

5.2 You may commercially distribute your resulting audio and stems where you hold the necessary rights and permissions.

5.3 SizeSynth.com claims no ownership of your output.

5.4 The licence grants no rights in third-party recordings or other material.

5.5 You may make copies needed for authorised installation, execution and backup, use permitted configuration and settings, and install authorised updates.

6.1 You must not: (a) redistribute, sell, rent, lend or sublicense the software or access to it; (b) share your account or activation credentials, use another person's credentials, or allow another person to use your licence; (c) exceed the purchased computer allowance; (d) copy the software beyond the licensed installation and backup rights; (e) modify, create unauthorised derivative software from, decompile, disassemble or reverse-engineer the proprietary software; (f) remove copyright, ownership or licence notices; (g) bypass, tamper with or defeat activation, validation or computer limits, or manufacture or distribute unauthorised activation credentials; (h) use SizeSynth.com branding to imply endorsement of your own product or service.

6.2 You must not sell, gift, share or transfer your existing licence, resell access, or share account credentials or activation keys, subject to mandatory law.

6.3 These restrictions apply except where SizeSynth.com expressly permits the activity, mandatory law permits it notwithstanding a contractual restriction, or a separate third-party component licence grants the relevant rights.

6.4 Lawful observation, study, testing and interoperability activities remain permitted within the conditions of the applicable statutory exception.

6.5 Required third-party licences and notices remain applicable; these terms do not remove their independently granted freedoms.

7.1 Use the SizeSynth account that owns your purchased SizeStem entitlement.

7.2 Keep your account credentials confidential; the restrictions in section 6 apply.

7.3 For assistance with suspected unauthorised account use, contact us using section 20.

7.4 Signing out does not release a registered computer, cancel a purchase or close your account.

7.5 Replacing a computer, recovering a lost device or changing the same owner's account email is account or device management, not a transfer to another person.

7.6 Refreshing expired authorisation retains the same owner's activation and computer allocation; it is not a repurchase.

7.7 Account closure and retained records are addressed in section 14.

7.8 Cancellation and refunds are addressed in section 12.

8.1 Installation does not require a paid licence.

8.2 Activation requires verification of your owning account and purchased SizeStem entitlement, and your affirmative acceptance of these Terms.

8.3 Activation is handled through your account; you do not need to enter a licence reference or a separate activation key.

8.4 Initial activation and successful renewal require internet access and signed authorisation from the licensing service.

8.5 Separation runs locally; activation does not require uploading your recordings or stem contents.

8.6 Each successful validation can provide authorisation for up to 30 days for the licensed product and computer.

8.7 The supplied expiry determines whether you can open another licensed instance.

8.8 A failed check, service outage, opening the app or changing the computer clock does not extend that expiry.

8.9 In the last seven offline days, the app displays a nonblocking reminder to reconnect.

8.10 Installer acceptance does not purchase, create or activate a licence, or replace authenticated account-bound acceptance or separate purchase-specific consent.

9.1 An instance opened while its authorisation is valid remains fully usable until you close it, even if that authorisation expires during use.

9.2 Playback, stopping and restarting playback, and new renders remain available.

9.3 Ordinary expiry or a failed renewal does not interrupt that admitted opening or impose a 24-hour limit.

9.4 Loading another track or showing or hiding the app window does not close an existing instance.

9.5 Closing and reopening the app, or opening another instance, does not carry that permission forward or extend the saved authorisation.

9.6 Opening a new instance after expiry requires fresh owner sign-in and valid refreshed signed authorisation for the same product and computer.

9.7 Sign-in alone, a failed or cancelled attempt, or an outage does not permit licensed use.

9.8 Ordinary expiry does not require buying the app again.

10.1 Supported releases, platforms, hardware requirements and tested compatibility are stated in the product offer.

10.2 Processing performance depends on your hardware and recording.

10.3 Platform or accelerator support is included only where offered and supported for the supplied release.

10.4 The base Windows installation performs separation on the CPU.

10.5 An optional accelerator is a separate download for a validated hardware, operating-system, driver and runtime combination.

10.6 CPU processing remains available if accelerator detection, download, activation or calibration fails.

10.7 The installed app includes a copy of these terms.

10.8 If SizeSynth.com ceases trading, licence requirements will be removed for existing purchases so owners can continue using SizeStem.

10.9 SizeSynth.com may email relevant update and service information about your purchased SizeStem app, including genuine software, security, compatibility, licensing and support information needed for access.

10.10 This does not require agreement to newsletters, paid-upgrade advertising or other-product offers.

10.11 Optional other-product marketing remains separate; declining or withdrawing it does not affect purchase or lawful access.

10.12 Your lifetime licence includes future SizeStem updates as set out in section 4.

10.13 Changes and any applicable update or security obligations are addressed in section 19.

11.1 The launch price is USD 39.99 per SizeStem licence unit, paid once and including applicable taxes.

11.2 There is no launch discount, and applicable tax is not added on top of that amount.

11.3 The product, quantity and total payable are shown before payment.

11.4 Supply of the software and purchased access follows the delivery arrangements stated in the product offer and checkout.

11.5 Installer acceptance does not confirm payment or delivery.

11.6 Required purchase information and confirmation must accompany the actual sale.

11.7 For a purchase through an authorised reseller or merchant of record, the seller identified at checkout and on the receipt handles the sale under its applicable purchase terms.

11.8 Where Paddle supplies checkout, its buyer terms apply to its sale and payment service.

11.9 These terms govern your SizeStem software licence with SizeSynth.com.

11.10 Neither set of terms removes mandatory consumer rights or changes the actual checkout price, product and quantity you agree to.

12.1 UK statutory cancellation rights normally provide a 14-day cancellation period in accordance with applicable law.

12.2 Acceptance of these licence terms alone does not end that right.

12.3 For immediate digital supply to end the cancellation right, prior express consent to supply, acknowledgement of loss of the right and the required durable confirmation must be obtained.

12.4 Acceptance of these terms, immediate-supply consent and the loss-of-cancellation acknowledgement are separate explicit choices.

12.5 The cancellation right ends on commencement of supply where those legal requirements are met.

12.6 Installer or app acceptance does not constitute that purchase-specific consent or confirmation.

12.7 Rights concerning faulty or misdescribed digital content and applicable repair, replacement or price reduction remain unaffected.

12.8 After cancellation rights have lawfully expired or been lost, discretionary cancellation is exceptional.

12.9 Non-waivable rights in every applicable territory remain unaffected.

12.10 Cancellation and refund requests should be sent to the contact in section 20, with the purchase reference where available.

12.11 Mandatory rights and applicable seller terms remain unaffected.

12.12 A confirmed full refund removing the last valid SizeStem unit affects licensed access as set out in section 15.

13.1 SizeStem is licensed, not sold.

13.2 SizeSynth.com and its licensors retain their rights, title and interest in the proprietary software, code, interface, artwork, branding, documentation and updates.

13.3 All rights not expressly granted are reserved.

14.1 Personal-data processing for accounts, purchases, licensing and support is described in the shared Privacy Policy: https://sizesynth.com/privacy/.

14.2 These software terms do not create a separate or conflicting retention schedule.

14.3 The Privacy Policy explains the applicable retention periods, review, closure and erasure arrangements and your rights.

14.4 Audio and stem contents are not required for licence activation.

14.5 Necessary identity, purchase and licence linkage, and relevant substantiated dispute or legal-duty records, can survive account closure or revocation where justified by purpose, necessity and applicable rights.

14.6 Minimum linkage needed for a still-valid lifetime entitlement remains available after account closure; closure alone does not end that entitlement.

14.7 This is not permission to retain all information indefinitely.

14.8 Reading or acknowledging the Privacy Policy is not blanket consent to processing or permission for marketing, and does not replace the separate licence, immediate-supply and cancellation acknowledgements.

14.9 Purchase, installation or licence-grant dates are not proof of consent that was not actually recorded.

14.10 Privacy enquiries may be sent to the contact in section 20.

14.11 Do not disclose passwords or payment-card details.

15.1 SizeSynth.com may terminate the affected licence for a material breach only where termination is lawful and proportionate.

15.2 The affected licence and reasons must be identified, with legally required notice and a reasonable opportunity to remedy a remediable breach where required by law and the circumstances.

15.3 This is not an unrestricted right to cancel a lifetime purchase.

15.4 Prohibited sharing, resale or transfer may result in revocation of the affected licence and denial of new licensed openings, subject to mandatory law and any required notice or remedy.

15.5 Confirmed enforcement affects open instances as set out in sections 9 and 15.

15.6 If a confirmed full refund removes your last valid SizeStem licence unit, open instances using that affected entitlement stop licensed processing when they receive reliable current confirmation.

15.7 New licensed openings are also denied.

15.8 A pending refund, a network error, a refund for another product, or a refund that leaves other valid SizeStem units does not trigger this restriction.

15.9 If a licence is revoked for prohibited sharing or resale, open instances using the affected licence stop licensed processing when they receive reliable current confirmation.

15.10 New licensed openings using that revoked entitlement are denied.

15.11 Other product licences and genuinely valid remaining SizeStem units are not removed by that event.

15.12 An offline instance may not receive confirmation immediately.

15.13 These restrictions apply when reliable confirmation is received; instantaneous offline notification is not promised.

15.14 A general access, network, transport or sign-in error is not confirmation of revocation.

15.15 Pending or partial refunds, disputes, chargebacks and reversals are not, by themselves, confirmed enforcement.

15.16 Ordinary time expiry continues to follow the until-closed rule above.

15.17 Deletion of your audio or account and transfer of ownership of exported files are not enforcement remedies authorised by these terms.

15.18 Separate account procedures remain applicable.

15.19 Refund-related access restrictions and enforcement for prohibited sharing or resale follow section 15 and applicable mandatory law.

15.20 Other product purchases and genuinely valid remaining SizeStem units are not cancelled by termination of the affected entitlement.

15.21 Following lawful termination, you must stop using the affected proprietary app under that entitlement and remove proprietary copies you are no longer authorised to keep.

15.22 This does not require destruction of your own audio, projects or output, independently licensed components, or records and copies which the law permits you to retain for rights, remedies or evidence.

15.23 Ordinary authorisation expiry, an update, proposed new terms, account deletion or refusal of optional marketing is not by itself a material-breach decision or a ground for arbitrary withdrawal of a valid lifetime entitlement.

15.24 Ordinary expiry continues to follow section 9.

15.25 These terms do not authorise deletion of your audio or account as an enforcement remedy.

16.1 If you believe a licence or account restriction is wrong, email Contact@sizesynth.com with your account email, affected app or decision reference and explanation.

16.2 SizeSynth.com will arrange human review of your explanation and relevant evidence and send the outcome and reasons within 14 calendar days of receiving your appeal, including correction where appropriate.

16.3 The explanation and relevant decision and appeal records are retained under the shared Privacy Policy.

16.4 An appeal does not automatically restore access or create a discretionary refund.

16.5 It does not delay or remove a correction, refund or other remedy required by law, or prevent statutory complaints, data-rights requests or lawful dispute routes.

16.6 Applicable safeguards for a solely automated decision with legal or similarly significant effects remain available, including decision information, representations, human intervention and a way to challenge it.

17.1 Mandatory rights come first.

17.2 Nothing in these terms excludes, restricts or replaces mandatory consumer rights, digital-content quality, description or fitness-for-purpose obligations, lawful repair, replacement, price reduction, refund or cancellation rights, or applicable remedies for damage to a device or other digital content.

17.3 Early-supply consent does not waive remedies for faulty content.

17.4 Mandatory protections in your country remain available.

17.5 Subject to the overriding protections above, SizeStem is provided AS IS and AS AVAILABLE to the extent permitted by applicable law.

17.6 SizeSynth.com makes no additional promise of uninterrupted operation, freedom from every error, or compatibility with every third-party system.

17.7 This does not displace express descriptions or promises, your purchased lifetime entitlement, or any mandatory obligation or remedy, and is not an exemption from responsibility where such an exemption would be unlawful or unfair.

17.8 You are responsible for lawful use of recordings, compliance with supplied installation and operating instructions, and backups of valuable audio and projects.

17.9 A result differing from an artistic preference does not alone establish a fault.

17.10 These obligations do not remove SizeSynth.com's duties concerning the software's description, quality and fitness for purpose, or rights arising from faulty digital content.

18.1 Nothing excludes or limits liability for death or personal injury caused by negligence, fraud, fraudulent misrepresentation, or any other liability that cannot lawfully be excluded or limited.

18.2 These protections override every disclaimer, liability cap, loss exclusion, termination and governing-law clause in these terms.

18.3 Subject to those overriding protections, and only where lawful, fair and reasonable in the circumstances, SizeSynth.com's total liability arising out of or relating to the affected SizeStem licence is limited to the amount actually paid for the affected SizeStem licence entitlement giving rise to the claim, identified consistently with the actual purchase record.

18.4 This concerns the affected entitlement, not unrelated purchases.

18.5 It is not a rolling-period limit or a list-price limit; it is not reduced by subtracting refunds or by inventing a per-unit allocation not identified in the actual purchase record.

18.6 Mandatory remedies and non-excludable liabilities are not subject to this cap.

18.7 On the same lawful, fair and reasonable basis, SizeSynth.com excludes indirect or consequential losses and loss of business profits, revenue, opportunity or goodwill.

18.8 These exclusions do not remove a consumer's recoverable reasonably foreseeable loss merely by describing it as consequential or indirect, or remove a mandatory remedy or non-excludable liability.

18.9 SizeSynth.com is responsible for reasonably foreseeable loss or damage caused by its breach of these terms or failure to exercise legally required reasonable care and skill, subject only to limitations that can lawfully and fairly apply.

18.10 To the extent permitted by applicable law, SizeSynth.com excludes liability for loss that is not reasonably foreseeable and for failure caused solely by unlawful use, unauthorised changes, or external equipment or services which it did not cause and could not reasonably prevent.

18.11 These exclusions do not excuse SizeSynth.com's own breach, negligence or failure to meet a legal obligation.

19.1 Installer acceptance does not replace earlier purchase terms or consent records.

19.2 Existing lifetime licence rights, purchased computer capacity, accrued rights and statutory remedies remain unaffected.

19.3 The creation date for these terms is shown at the beginning of this document.

19.4 SizeSynth.com may issue software updates and propose revised terms.

19.5 Proposed terms will be supplied before any new agreement, with genuine affirmative acceptance where required.

19.6 The scope of changes and any update or security obligations must be explained without removing mandatory rights.

19.7 Earlier accepted terms, their exact content, and existing genuine consent, purchase, installation and licence-grant records must be preserved rather than retrospectively rewritten.

19.8 Ordinary app launch, licence refresh, silence or installing an update is not proof of acceptance of different terms.

19.9 Purchase, installation or licence-grant events are not by themselves proof of separate assent or immediate-supply consent.

19.10 A software update or change to these terms does not arbitrarily withdraw accrued rights or already-purchased lifetime access under the applicable accepted contract.

20.1 These terms are governed by the law of England and Wales, subject to mandatory protections given to you by applicable law, including those available where you habitually live.

20.2 For consumers, this does not remove access to a court or dispute route protected by mandatory jurisdiction rules.

20.3 For business users, the courts of England and Wales have jurisdiction to the extent that agreement is lawful.

20.4 SizeStem is supplied and licensed by SizeSynth.com, based in Liverpool, United Kingdom.

20.5 SizeSynth.com is operated by SizeSynth, trading as SizeSynth.com.

20.6 Website: https://sizesynth.com

20.7 Support, business enquiries, complaints and privacy requests: Contact@sizesynth.com

20.8 Enquiries and complaints should include the purchase reference and relevant issue details.

20.9 Do not disclose passwords.

20.10 Support is available by email using the contact in section 20.

20.11 Supported compatibility and specific support commitments are stated in the product offer.