# Controlling space after heading when doublespaced

I'm writing a document with both doublespaced and singlespaced sections. I'm using the setspace package to do the doublespacing and the koma-script report class for the document. In the double spaced environment the space after the heading is larger. This is obvious in my MWE:

\documentclass[12pt, letterpaper]{scrreprt}
\usepackage{setspace}
\usepackage{lipsum}

\begin{document}
\chapter{chapter1}
\doublespacing
\lipsum[1-2]

\singlespacing
\chapter{chapter2}
\lipsum[1-2]
\end{document}


I really want the space to be the same regardless of the line spacing, the first line should start a fixed distance after the heading. I can tweak it manually with a vspace but I figure there is a proper way to do this and if I tweak it manually then sections I don't have control over like the bibliography. How can I fix this. I tried adjusting the parskip before the section but this also moves the heading down.

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You're starting from a false premise, in my opinion: why should a chapter be double spaced and another one single spaced? –  egreg Dec 31 '12 at 17:09
@egreg its for a PhD thesis and the school requires that your main text be double spaced while any acknowledgements and references are single spaced. If it was up to me I would get rid of all the ugly double spaced text. –  s0rce Dec 31 '12 at 17:22
I feared you would answer in this way; and you have all my sympathy. :) –  egreg Dec 31 '12 at 17:25
and to add to the pain you must work as hard as possible to replicate the look of a typewriter for the titlepage. –  s0rce Dec 31 '12 at 17:27

This might be automated, but it seems that

\cleardoublepage
\singlespacing
\chapter{Double spaced chapter}

\doublespacing\nointerlineskip


for a double spaced chapter and

\cleardoublepage
\singlespacing
\chapter{Single spaced chapter}


for a single spaced chapter may be what you need.

Some problems might remain for the cases where \chapter is automatically generated, such as the table of contents.

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