API 325 ACA (Active Combining Amplifier) Summing Line driver card w. 2520 DOA Vintage (Model 535 today)

The PCB consists of four amplifiers: two inverting summing amplifiers and two booster amplifiers based on the API 325 card.

Each amplifier uses 4 pcs 2520-style discreet opamp and API AP2623-4- transformers.

This can be used as a Line amp card for console output. So you can add API sound to your Stereo mix bus output and same time stereo monitor out. Or you can use it as a summing amplifier.
It is a very convenient package to work with. 4 channels on one PCB. Un-balanced in - Balanced out

US and EU parcels ship via UPS, ETA 1-7 working days from pickup day zero. That also applies to most locations worldwide.

All shipments are fully insured.

Bigger shipments requiring pallets or custom made crates ship to US, CA, JP, CN, AU and other outside of EU locations via DHL Air Freight, ETA is normally approx. 7-14 working days from pickup day zero.

Big shipments inside EU ship via different freight companies, recently mostly via ACE Logistics. Freight forwarders can use different courier companies for deliveries to final destinations.

Palletising and crating time can vary depending on the size of the shipment and packaging queue. We pack all our shipments with great care.

You are most welcome to pick your order up yourself from our Retrosonic Pro Audio showroom, studio and warehouse in Tallinn, Estonia.

We ship worldwide – contact us for a personal shipping quote or any other questions.

VAT (Value Added Tax) can be deducted if you have a company with a valid EU VAT number or if you're based outside of the EU. Non-EU buyers pay all and any import tax and duty as regulated by their local customs.