diff --git a/RTCP/Cobalt/OutputProc/src/TBB_Frame.h b/RTCP/Cobalt/OutputProc/src/TBB_Frame.h
index 6866262e6832821311f3848aebb8109f310d408c..983e85c5d0aef1c6829285295a8fb0dbb3dc0d19 100644
--- a/RTCP/Cobalt/OutputProc/src/TBB_Frame.h
+++ b/RTCP/Cobalt/OutputProc/src/TBB_Frame.h
@@ -32,6 +32,11 @@ namespace LOFAR
 {
   namespace Cobalt
   {
+      /**
+       * This reflects the fact that LOFAR's TBB boards can produce spectral
+       * time series for a maximum of 487 frequency bands.
+       */
+      const uint32_t MAX_TBB_SPECTRAL_SUBBANDS{487U};
 
     /*
      * Incoming UDP frame format.
diff --git a/RTCP/Cobalt/OutputProc/src/TBB_Writer.cc b/RTCP/Cobalt/OutputProc/src/TBB_Writer.cc
index f8cb2998c1ca99c898051130aff2a95e39636b7d..8ce5afaaed3693deee12efb566a4f71872da379b 100644
--- a/RTCP/Cobalt/OutputProc/src/TBB_Writer.cc
+++ b/RTCP/Cobalt/OutputProc/src/TBB_Writer.cc
@@ -74,7 +74,7 @@ namespace LOFAR
       if (operatingMode == TBB_SPECTRAL_MODE) {
         vector<unsigned> tbbSubbandList(parset.getUint32Vector("Observation.TBB.TBBsetting.subbandList", true));
         size_t nrSubbands = tbbSubbandList.size();
-        if (nrSubbands == 0 || nrSubbands > MAX_TBB_SPECTRAL_NSAMPLES) {
+        if (nrSubbands == 0 || nrSubbands > MAX_TBB_SPECTRAL_SUBBANDS) {
           throw APSException("TBB: spectral mode selected, but empty or too long Observation.TBB.TBBsetting.subbandList");
         }
         std::sort  (tbbSubbandList.begin(), tbbSubbandList.end());