Output Caps For Dehavilland Ultraverve

Ok here is what you do if you have the money. The total capacitance needed should be between 1.8uf - 2.8uf. Best option;

1) Jupiter copper foil caps 2.2uf. $200 for both at Sonic Craft. Place the Duelund .01uf silver foil bypass caps in parallel. $200 cost total from Part Connextion. This will transform your preamp in ways you thought were not possible.

If this is too much money then to this,

2) Jupiter copper foil cap 2.2uf only.....no bypass.

Be sure to place the outer foil end of the Jupiter cap on the input and the other side towards the output (rca jacks). The outer foil side is marked with a solid line next to the printing.  

These options will sound far more organic, real, and natural than the Mundorf caps.

Need the 600v Jupiter. 100v is for speaker crossovers. Expect the Duelund silver to improve everything top to bottom considerably. The impact they have is substantial improving the SQ of the output cap position by some 20%.  

No issues at all going into my friends mklll. Very easy to do. When I say no problem, I mean fitting the Jupiter and Duelund bypass. The Duelund silver foils are very small and the Jupiter’s fit.

The Duelund CAST is a great cap, but a 2.2uf value will be huge and cost you a Fortune! $900 for the two 2.2uf caps! My suggestion gives you as good sound quality for a lot less. The Duelund RS cap will sound great, but not as good as the Jupiter and Duelund silver foil combo. 

Some 100 hours gets you most of the way. 

Another good choice if you don’t want to parallel caps is to go with the Jupiter copper foil caps, 600vdv. Get the 2.2uf value. Sonic Craft sells them for $140 each or so. They are spectacular. Right up there with a Duelund CAST in this position. Make sure you order them matched within 1% of each other. Dimensions are......

1.562″ X 2.125″

Check to see see if they will fit.

What amp is being paired with this preamp and do know the input impedance of the amp? 

Well, that question is not as easy. Not sure the size of the cap will make that much of a difference. It really depends on the capacitance of the IC your using and the output impedance of the preamp. Yours has an output impedance of 600-1000 ohms depending on the volume and frequency. Impedance will rise as you turn it up.

Best case in an output impedance of under 500 ohms to avoid top end roll off on a long 4-6 meter IC. How long are your ICs and what are they? 

Correct. You get a gold star! Keep to total capacitance at 2.2uf to 2.8uf or so.  

I helped a v3 owner just this week with the same mod. He simply added the Duelund silver bypass caps and loves it!