diff --git a/experimental/AcousticSolver.cpp b/experimental/AcousticSolver.cpp
index fc875ffadb5a48fc9150c28150e7eeb723d2d00e..16bf845f3233a2cc163a6183b123d7afeb0ce9b6 100644
--- a/experimental/AcousticSolver.cpp
+++ b/experimental/AcousticSolver.cpp
@@ -42,62 +42,43 @@ public:
     dst= Kokkos::reduction_identity<value_type>::min();
   }
 };
-    
 
 KOKKOS_INLINE_FUNCTION
-double AcousticSolver::
-acoustic_dt(const Kokkos::View<const double*>& Vj,
-	    const Kokkos::View<const double*>& cj) const
+const Kokkos::View<const double*>
+AcousticSolver::computeRhoCj(const Kokkos::View<const double*>& rhoj,
+			     const Kokkos::View<const double*>& cj)
 {
-  const size_t nj = Vj.size();
-  double dt = std::numeric_limits<double>::max();
-
-  Kokkos::View<double*> Vj_cj("Vj_cj", nj);
-
-  Kokkos::parallel_for(nj, KOKKOS_LAMBDA(const int& j){
-      Vj_cj[j] = Vj[j]/cj[j];
+  Kokkos::View<double*> rhocj("rho_c", m_nj);
+  Kokkos::parallel_for(m_nj, KOKKOS_LAMBDA(const int& j) {
+      rhocj[j] = rhoj[j]*cj[j];
     });
-
-  Kokkos::parallel_reduce(nj, ReduceMin(Vj_cj), dt);
-
-  return dt;
+  return rhocj;
 }
 
-
 KOKKOS_INLINE_FUNCTION
-void AcousticSolver::computeExplicitFluxes(const Kokkos::View<const double*>& xr,
-					   const Kokkos::View<const double*>& xj,
-					   const Kokkos::View<const double*>& rhoj,
-					   const Kokkos::View<const double*>& uj,
-					   const Kokkos::View<const double*>& pj,
-					   const Kokkos::View<const double*>& cj,
-					   const Kokkos::View<const double*>& Vj,
-					   const Kokkos::View<const double*[2]>& Cjr,
-					   const Kokkos::View<const int*[2]>& cell_nodes,
-					   const Kokkos::View<const int*[2]>& node_cells,
-					   const Kokkos::View<const int*>& node_nb_cells,
-					   const Kokkos::View<const int*[2]>& node_cell_local_node,
-					   Kokkos::View<double*>& ur,
-					   Kokkos::View<double*[2]>& Fjr) const
+const Kokkos::View<const double*[2]>
+AcousticSolver::computeAjr(const Kokkos::View<const double*>& rhocj,
+			   const Kokkos::View<const double*[2]>& Cjr)
 {
-  // calcul de ur
-  const size_t nr = ur.size();
-  const size_t nj = uj.size();
-
-  Kokkos::View<double*> rhocj("rho_c", nj);
-  Kokkos::parallel_for(nj, KOKKOS_LAMBDA(const int& j) {
-      rhocj[j] = rhoj[j]*cj[j];
-    });
-
-  Kokkos::View<double*[2]> Ajr("Ajr", nj);
-  Kokkos::parallel_for(nj, KOKKOS_LAMBDA(const int& j) {
+  Kokkos::View<double*[2]> Ajr("Ajr", m_nj);
+  Kokkos::parallel_for(m_nj, KOKKOS_LAMBDA(const int& j) {
       for (int r=0; r<2; ++r) {
 	Ajr(j,r) = rhocj(j)*Cjr(j,r)*Cjr(j,r);
       }
     });
 
-  Kokkos::View<double*> Ar("Ar", nr);
-  Kokkos::parallel_for(nr, KOKKOS_LAMBDA(const int& r) {
+  return Ajr;
+}
+
+KOKKOS_INLINE_FUNCTION
+const Kokkos::View<const double*>
+AcousticSolver::computeAr(const Kokkos::View<const double*[2]>& Ajr,
+			  const Kokkos::View<const int*[2]>& node_cells,
+			  const Kokkos::View<const int*[2]>& node_cell_local_node,
+			  const Kokkos::View<const int*>& node_nb_cells)
+{
+  Kokkos::View<double*> Ar("Ar", m_nr);
+  Kokkos::parallel_for(m_nr, KOKKOS_LAMBDA(const int& r) {
       double sum = 0;
       for (int j=0; j<node_nb_cells(r); ++j) {
 	const int J = node_cells(r,j);
@@ -107,14 +88,21 @@ void AcousticSolver::computeExplicitFluxes(const Kokkos::View<const double*>& xr
       Ar(r) = sum;
     });
 
-  Kokkos::View<double*> invAr("invAr", nr);
-  Kokkos::parallel_for(nr, KOKKOS_LAMBDA(const int& r) {
-      invAr(r) = 1./Ar(r);
-    });
-
+  return Ar;
+}
 
-  Kokkos::View<double*> br("br", nr);
-  Kokkos::parallel_for(nr, KOKKOS_LAMBDA(const int& r) {
+KOKKOS_INLINE_FUNCTION
+const Kokkos::View<const double*>
+AcousticSolver::computeBr(const Kokkos::View<const double*[2]>& Ajr,
+			  const Kokkos::View<const double*[2]>& Cjr,
+			  const Kokkos::View<const double*>& uj,
+			  const Kokkos::View<const double*>& pj,
+			  const Kokkos::View<const int*[2]>& node_cells,
+			  const Kokkos::View<const int*[2]>& node_cell_local_node,
+			  const Kokkos::View<const int*>& node_nb_cells)
+{
+  Kokkos::View<double*> br("br", m_nr);
+  Kokkos::parallel_for(m_nr, KOKKOS_LAMBDA(const int& r) {
       double sum = 0;
       for (int j=0; j<node_nb_cells(r); ++j) {
 	const int J = node_cells(r,j);
@@ -124,69 +112,158 @@ void AcousticSolver::computeExplicitFluxes(const Kokkos::View<const double*>& xr
       br(r) = sum;
     });
 
-  Kokkos::parallel_for(nr, KOKKOS_LAMBDA(const int& r) {
+  return br;
+}
+
+KOKKOS_INLINE_FUNCTION
+Kokkos::View<double*>
+AcousticSolver::computeUr(const Kokkos::View<const double*>& Ar,
+			  const Kokkos::View<const double*>& br)
+{
+  const Kokkos::View<const double*> invAr = inverse(Ar);
+  Kokkos::View<double*> ur("ur", m_nr);
+  Kokkos::parallel_for(m_nr, KOKKOS_LAMBDA(const int& r) {
       ur[r]=br(r)*invAr(r);
     });
   ur[0]=0;
-  ur[nr-1]=0;
+  ur[m_nr-1]=0;
 
-  Kokkos::parallel_for(nj, KOKKOS_LAMBDA(const int& j) {
+  return ur;
+}
+
+KOKKOS_INLINE_FUNCTION
+Kokkos::View<double*[2]>
+AcousticSolver::computeFjr(const Kokkos::View<const double*[2]>& Ajr,
+			   const Kokkos::View<const double*>& ur,
+			   const Kokkos::View<const double*[2]>& Cjr,
+			   const Kokkos::View<const double*>& uj,
+			   const Kokkos::View<const double*>& pj,
+			   const Kokkos::View<const int*[2]>& cell_nodes)
+{
+  Kokkos::View<double*[2]> Fjr("Fjr", m_nj);
+
+  Kokkos::parallel_for(m_nj, KOKKOS_LAMBDA(const int& j) {
       for (int r=0; r<2; ++r) {
 	Fjr(j,r) = Ajr(j,r)*(uj(j)-ur(cell_nodes(j,r)))+Cjr(j,r)*pj(j);
       }
     });
+
+  return Fjr;
 }
 
-AcousticSolver::AcousticSolver(const long int& nj)
+KOKKOS_INLINE_FUNCTION
+double AcousticSolver::
+acoustic_dt(const Kokkos::View<const double*>& Vj,
+	    const Kokkos::View<const double*>& cj) const
 {
-  Kokkos::View<double*> xj("xj", nj);
-  Kokkos::View<double*> rhoj("rhoj", nj);
+  double dt = std::numeric_limits<double>::max();
 
-  Kokkos::View<double*> uj("uj", nj);
+  Kokkos::View<double*> Vj_cj("Vj_cj", m_nj);
 
-  Kokkos::View<double*> Ej("Ej", nj);
-  Kokkos::View<double*> ej("ej", nj);
-  Kokkos::View<double*> pj("pj", nj);
-  Kokkos::View<double*> Vj("Vj", nj);
-  Kokkos::View<double*> gammaj("gammaj", nj);
-  Kokkos::View<double*> cj("cj", nj);
-  Kokkos::View<double*> mj("mj", nj);
-  Kokkos::View<double*> inv_mj("inv_mj", nj);
+  Kokkos::parallel_for(m_nj, KOKKOS_LAMBDA(const int& j){
+      Vj_cj[j] = Vj[j]/cj[j];
+    });
+
+  Kokkos::parallel_reduce(m_nj, ReduceMin(Vj_cj), dt);
 
-  const int nr=nj+1;
+  return dt;
+}
 
-  Kokkos::View<double*>  xr("xr", nr);
+KOKKOS_INLINE_FUNCTION
+const Kokkos::View<const double*>
+AcousticSolver::inverse(const Kokkos::View<const double*>& x) const
+{
+  Kokkos::View<double*> inv_x("inv_x", m_nr);
+  Kokkos::parallel_for(m_nr, KOKKOS_LAMBDA(const int& r) {
+      inv_x(r) = 1./x(r);
+    });
 
-  const double delta_x = 1./nj;
+  return inv_x;
+}
 
-  Kokkos::parallel_for(nr, KOKKOS_LAMBDA(const int& r){
+KOKKOS_INLINE_FUNCTION
+void AcousticSolver::computeExplicitFluxes(const Kokkos::View<const double*>& xr,
+					   const Kokkos::View<const double*>& xj,
+					   const Kokkos::View<const double*>& rhoj,
+					   const Kokkos::View<const double*>& uj,
+					   const Kokkos::View<const double*>& pj,
+					   const Kokkos::View<const double*>& cj,
+					   const Kokkos::View<const double*>& Vj,
+					   const Kokkos::View<const double*[2]>& Cjr,
+					   const Kokkos::View<const int*[2]>& cell_nodes,
+					   const Kokkos::View<const int*[2]>& node_cells,
+					   const Kokkos::View<const int*>& node_nb_cells,
+					   const Kokkos::View<const int*[2]>& node_cell_local_node,
+					   Kokkos::View<double*>& ur,
+					   Kokkos::View<double*[2]>& Fjr)
+{
+  const Kokkos::View<const double*> rhocj  = computeRhoCj(rhoj, cj);
+  const Kokkos::View<const double*[2]> Ajr = computeAjr(rhocj, Cjr);
+
+  const Kokkos::View<const double*> Ar = computeAr(Ajr, node_cells, node_cell_local_node, node_nb_cells);
+  const Kokkos::View<const double*> br = computeBr(Ajr, Cjr, uj, pj,
+						   node_cells, node_cell_local_node, node_nb_cells);
+
+  ur  = computeUr(Ar, br);
+#warning understand why this call diminishes performances
+  // Fjr = computeFjr(Ajr, ur, Cjr, uj, pj, cell_nodes);
+  Kokkos::parallel_for(m_nj, KOKKOS_LAMBDA(const int& j) {
+      for (int r=0; r<2; ++r) {
+  	Fjr(j,r) = Ajr(j,r)*(uj(j)-ur(cell_nodes(j,r)))+Cjr(j,r)*pj(j);
+      }
+    });
+}
+
+AcousticSolver::AcousticSolver(const long int& nj)
+  : m_nj(nj),
+    m_nr(nj+1)
+{
+  Kokkos::View<double*> xj("xj",m_nj);
+  Kokkos::View<double*> rhoj("rhoj",m_nj);
+
+  Kokkos::View<double*> uj("uj",m_nj);
+
+  Kokkos::View<double*> Ej("Ej",m_nj);
+  Kokkos::View<double*> ej("ej",m_nj);
+  Kokkos::View<double*> pj("pj",m_nj);
+  Kokkos::View<double*> Vj("Vj",m_nj);
+  Kokkos::View<double*> gammaj("gammaj",m_nj);
+  Kokkos::View<double*> cj("cj",m_nj);
+  Kokkos::View<double*> mj("mj",m_nj);
+  Kokkos::View<double*> inv_mj("inv_mj",m_nj);
+
+  Kokkos::View<double*>  xr("xr", m_nr);
+
+  const double delta_x = 1./m_nj;
+
+  Kokkos::parallel_for(m_nr, KOKKOS_LAMBDA(const int& r){
       xr[r] = r*delta_x;
     });
 
-  Kokkos::View<int*[2]> cell_nodes("cell_nodes",nj,2);
-  Kokkos::View<int*[2]> node_cells("node_cells",nr,2);
-  Kokkos::View<int*[2]> node_cell_local_node("node_cells",nr,2);
-  Kokkos::View<int*> node_nb_cells("node_cells",nr);
+  Kokkos::View<int*[2]> cell_nodes("cell_nodes",m_nj,2);
+  Kokkos::View<int*[2]> node_cells("node_cells",m_nr,2);
+  Kokkos::View<int*[2]> node_cell_local_node("node_cells",m_nr,2);
+  Kokkos::View<int*> node_nb_cells("node_cells",m_nr);
 
-  Kokkos::parallel_for(nr, KOKKOS_LAMBDA(const int& r){
+  Kokkos::parallel_for(m_nr, KOKKOS_LAMBDA(const int& r){
       node_nb_cells(r) = 2;
     });
   node_nb_cells(0) = 1;
-  node_nb_cells(nr-1) = 1;
+  node_nb_cells(m_nr-1) = 1;
 
   node_cells(0,0) = 0;
-  Kokkos::parallel_for(nr-2, KOKKOS_LAMBDA(const int& r){
+  Kokkos::parallel_for(m_nr-2, KOKKOS_LAMBDA(const int& r){
       node_cells(r+1,0) = r;
       node_cells(r+1,1) = r+1;
     });
-  node_cells(nr-1,0) = nj-1;
+  node_cells(m_nr-1,0) =m_nj-1;
 
   Kokkos::parallel_for(nj, KOKKOS_LAMBDA(const int& j){
       cell_nodes(j,0) = j;
       cell_nodes(j,1) = j+1;
     });
 
-  Kokkos::parallel_for(nr, KOKKOS_LAMBDA(const int& r){
+  Kokkos::parallel_for(m_nr, KOKKOS_LAMBDA(const int& r){
       for (int J=0; J<node_nb_cells(r); ++J) {
 	int j = node_cells(r,J);
 	for (int R=0; R<2; ++R) {
@@ -243,7 +320,7 @@ AcousticSolver::AcousticSolver(const long int& nj)
   int itermax=std::numeric_limits<int>::max();
   int iteration=0;
 
-  Kokkos::View<double*[2]> Cjr("Cjr", nj);
+  Kokkos::View<double*[2]> Cjr("Cjr",m_nj);
   Kokkos::parallel_for(nj, KOKKOS_LAMBDA(const int& j) {
       Cjr(j,0)=-1;
       Cjr(j,1)= 1;
@@ -258,16 +335,17 @@ AcousticSolver::AcousticSolver(const long int& nj)
       t=tmax;
     }
     
-    Kokkos::View<double*> ur("ur", nr);
-    Kokkos::View<double*[2]> Fjr("Fjr", nr);
-
+    Kokkos::View<double*> ur;
+    // Kokkos::View<double*[2]> Fjr;
+    Kokkos::View<double*[2]> Fjr("Fjr", m_nj);
+  
     computeExplicitFluxes(xr, xj,
 			  rhoj, uj, pj, cj, Vj, Cjr,
 			  cell_nodes, node_cells, node_nb_cells, node_cell_local_node,
 			  ur, Fjr);
 
-    Kokkos::View<double*> new_uj("new_uj", nj);
-    Kokkos::View<double*> new_Ej("new_Ej", nj);
+    // Kokkos::View<double*> new_uj("new_uj",m_nj);
+    // Kokkos::View<double*> new_Ej("new_Ej",m_nj);
 
     Kokkos::parallel_for(nj, KOKKOS_LAMBDA(const int& j){
 	double momentum_fluxes = 0;
@@ -277,25 +355,23 @@ AcousticSolver::AcousticSolver(const long int& nj)
 	  momentum_fluxes += Fjr(j,R);
 	  energy_fluxes += Fjr(j,R)*ur[r];
 	}
-	new_uj[j] = uj[j] - dt/mj[j]*(momentum_fluxes);
-	new_Ej[j] = Ej[j] - dt/mj[j]*(energy_fluxes);
+	uj[j] -= dt/mj[j]*(momentum_fluxes);
+	Ej[j] -= dt/mj[j]*(energy_fluxes);
       });
 
-    uj=new_uj;
-    Ej=new_Ej;
+    // uj=new_uj;
+    // Ej=new_Ej;
 
     Kokkos::parallel_for(nj, KOKKOS_LAMBDA(const int& j) {
 	ej[j] = Ej[j] - 0.5 * uj[j]*uj[j];
       });
 
-    Kokkos::View<double*> xr_new("new_xr", nr);
+    // Kokkos::View<double*> xr_new("new_xr", m_nr);
 
-    Kokkos::parallel_for(nr, KOKKOS_LAMBDA(const int& r){
-      xr_new[r] = xr[r] + dt*ur[r];
+    Kokkos::parallel_for(m_nr, KOKKOS_LAMBDA(const int& r){
+	xr[r] += dt*ur[r];
       });
 
-    xr = xr_new;
-
     Kokkos::parallel_for(nj, KOKKOS_LAMBDA(const int& j){
       xj[j] = 0.5*(xr[j]+xr[j+1]);
       Vj[j] = xr[j+1]-xr[j];
@@ -310,6 +386,13 @@ AcousticSolver::AcousticSolver(const long int& nj)
     ++iteration;
   }
 
+  {
+    std::ofstream fout("rho");
+    for (int j=0; j<nj; ++j) {
+      fout << xj[j] << ' ' << rhoj[j] << '\n';
+    }
+  }
+
   std::cout << "* " << rang::style::underline << "Final time" << rang::style::reset
 	    << ":  " << rang::fgB::green << t << rang::fg::reset << " (" << iteration << " iterations)\n";
 
diff --git a/experimental/AcousticSolver.hpp b/experimental/AcousticSolver.hpp
index ba1462770b4bb1018f0f4945cfe0892bce2a09ab..d8429d5acc023acea9ef6930c8de1306f0bc1370 100644
--- a/experimental/AcousticSolver.hpp
+++ b/experimental/AcousticSolver.hpp
@@ -7,8 +7,43 @@ class AcousticSolver
 {
 private:
 
-  inline double e(double rho, double p, double gamma) const;
-  inline double p(double rho, double e, double gamma) const;
+  inline const Kokkos::View<const double*>
+  computeRhoCj(const Kokkos::View<const double*>& rhoj,
+	       const Kokkos::View<const double*>& cj);
+
+  inline const Kokkos::View<const double*[2]>
+  computeAjr(const Kokkos::View<const double*>& rhocj,
+	     const Kokkos::View<const double*[2]>& Cjr);
+
+  inline const Kokkos::View<const double*>
+  computeAr(const Kokkos::View<const double*[2]>& Ajr,
+	    const Kokkos::View<const int*[2]>& node_cells,
+	    const Kokkos::View<const int*[2]>& node_cell_local_node,
+	    const Kokkos::View<const int*>& node_nb_cells);
+
+  inline const Kokkos::View<const double*>
+  computeBr(const Kokkos::View<const double*[2]>& Ajr,
+	    const Kokkos::View<const double*[2]>& Cjr,
+	    const Kokkos::View<const double*>& uj,
+	    const Kokkos::View<const double*>& pj,
+	    const Kokkos::View<const int*[2]>& node_cells,
+	    const Kokkos::View<const int*[2]>& node_cell_local_node,
+	    const Kokkos::View<const int*>& node_nb_cells);
+
+  Kokkos::View<double*>
+  computeUr(const Kokkos::View<const double*>& Ar,
+	    const Kokkos::View<const double*>& br);
+
+  Kokkos::View<double*[2]>
+  computeFjr(const Kokkos::View<const double*[2]>& Ajr,
+	     const Kokkos::View<const double*>& ur,
+	     const Kokkos::View<const double*[2]>& Cjr,
+	     const Kokkos::View<const double*>& uj,
+	     const Kokkos::View<const double*>& pj,
+	     const Kokkos::View<const int*[2]>& cell_nodes);
+
+  const Kokkos::View<const double*>
+  inverse(const Kokkos::View<const double*>& x) const;
 
   inline double acoustic_dt(const Kokkos::View<const double*>& Vj,
 			    const Kokkos::View<const double*>& cj) const;
@@ -26,9 +61,13 @@ private:
 				    const Kokkos::View<const int*>& node_nb_cells,
 				    const Kokkos::View<const int*[2]>& node_cell_local_node,
 				    Kokkos::View<double*>& ur,
-				    Kokkos::View<double*[2]>& Fjr) const;
+				    Kokkos::View<double*[2]>& Fjr);
 
   struct ReduceMin;
+
+  const long int m_nj;
+  const long int m_nr;
+
 public:
   AcousticSolver(const long int& nj);
 };