- Cup: Ø 32 mm - Medium deep - Rim: 8.5 mm - Bore: 8.35 mm - Open backbore - Model PT-89 is suitable for medium-large and large-bore C and B tubas - The response is stable, even in the deep tones with wide tubas - The sound is well centered but dark - Gold-plated EUR 222.00 - See more - Buy online