Primrose Audio exists for audiophile specific requirements.
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Primrose can better serve the needs of audio hobbyist and one time purchasers of toroid products. For over 20 years, Sum R has assisted audiophiles through our transformer sales desk, but now we have organized the audio sales with a separate name and purpose.
Primrose can concentrate it’s energies on audiophile requirements, while Sum R continues to build all quality transformer products
Whether your needs are for power or audio toroid requirements, Primrose will answer your questions and provide the best designs and products for your applications.