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AirTight ATM-300 - new Coupling Caps

So I want to replace the coupling caps in my Airtight 300B amp. The original ones are $5 Sprague orange drops. 0,1uF interstage caps between input tube (12AU7) and driver tube (12BH7A) and 0,47uF between driver tube and 300B.

I love the amplifier, it is very resolving and airy with great soundstage separation. However I miss some body and fullness, and tighter bass, hope new coupling caps can help with this. I like a natural sound with lots of body and texture, good detail and a tight and deep low end.

I have read alot of forum posts and narrowed my choices down to these 3;

Duelund CAST cu sn tinned copper

Jupiter copper foil paper and wax

V-cap ODAM

I have read that some capacitors are best used in lower voltage applications and others are better in higher voltage applications, so I am open to using different brands in interstage/300B coupling. 

Please share your experiences, impressions and recommendations. Not necessarily with the Airtight, but preferably used as a coupling cap.

rubjel
rubjel OP
16 posts
 

Hi Erik, yes I am absolutely sure they are coupling caps between the different stages. They are rated for 400V and 600V.

Post removed 
rubjel OP
16 posts
 

Thanks for the suggestion @viridian. I'm not necessarily interested in keeping the Airtight voicing.

Post removed 
rubjel OP
16 posts
 

@viridian I'll just put the original caps back in if that's an issue.

Was hoping to get more response related to my question.

My impressions after reading here and other forums;
V-Cap ODAMS; detailed and neutral but some find it a bit thin? Also reported to sound quite different in high/low voltage situations.

Jupiter copper foil; Organic, detailed with alot of texture and body. 

Duelund cast cusn; the top choice for speaker XO. I think @grannyring mentioned it might be to bright in electronics?

Someone also said it lacks bass when used as coupling cap.

Have looked at HumbleHomemadeHifi, but he only used the caps in speaker crossovers.

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